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The World Health Organization (WHO) states that in developing nations, there are three million cases of agrochemical poisoning. The prolonged intensive and indiscriminate use of agrochemicals adversely affected the soil biodiversity, agricultural sustainability, and food safety, bringing in long-term harmful effects on nutritional security, human and animal health. Most of the agrochemicals negatively affect soil microbial functions and biochemical processes. The alteration in diversity and composition of the beneficial microbial community can be unfavorable to plant growth and development either by reducing nutrient availability or by increasing disease incidence. Currently, there is a need for qualitative, innovative, and demand-driven research in soil science, especially in developing countries for facilitating of high-quality eco-friendly research by creating a conducive and trustworthy work atmosphere, thereby rewarding productivity and merits. Hence, we reviewed (1) the impact of various agrochemicals on the soil microbial diversity and environment; (2) the importance of smallholder farmers for sustainable crop protection and enhancement solutions, and (3) management strategies that serve the scientific community, policymakers, and land managers in integrating soil enhancement and sustainability practices in smallholder farming households. The current review provides an improved understanding of agricultural soil management for food and nutritional security.
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Land 2020, 9, 34; doi:10.3390/land9020034
Impact of Agrochemicals on Soil Microbiota and
Management: A Review
Ram Swaroop Meena 1,2, Sandeep Kumar 3, Rahul Datta 4,*, Rattan Lal 2, Vinod Vijayakumar 5,
Martin Brtnicky 4, Mahaveer Prasad Sharma 6, Gulab Singh Yadav 2,7, Manoj Kumar Jhariya 8,
Chetan Kumar Jangir 3, Shamina Imran Pathan 9, Tereza Dokulilova 4, Vaclav Pecina 4 and
Theodore Danso Marfo 10
1 Department of Agronomy, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi 221 005,
2 Carbon Management and Sequestration Centre, The Ohio State University, Columbus, OH 43210, USA; (R.L.); (G.S.Y.)
3 ICAR-National Academy of Agricultural Research Management (NAARM), Hyderabad 500030, Telangana,
India; (S.K.); (C.K.J.)
4 Department of Agrochemistry, Soil Science, Microbiology and Plant Nutrition, Faculty of Agrisciences,
Mendel University in Brno, Zemedelska 1, Brno 61300, Czech Republic; (M.B.); (T.D.); (V.P.)
5 College of Food, Agricultural, and Environmental Sciences, The Ohio State University, Columbus,
OH 43210, USA;
6 Microbiology Laboratory, ICAR-Indian Institute of Soybean Research, Khandwa Road,
Indore (MP) 452001, India;
7 ICAR Research Complex for NEH Region, Lembucherra 799210, India
8 Department of Farm Forestry, University Teaching Department, Sant Gahira Guru Vishwavidyalaya
(Formerly, Sarguja University), Sarguja, Ambikapur 497001, India;
9 Department of Agri-food, environmental, Forestry Science and Technology (DAGRI),
University of Florence, Piazzale delle Cascine 28, 50144 Florence, Italy;
10 Department of Geology and Pedology, Mendel University in Brno, Zemedelska 1, Brno 61300,
Czech Republic;
* Correspondence:; Tel.: +420-773990283
Received: 31 December 2019; Accepted: 17 January 2020; Published: 23 January 2020
Abstract: The World Health Organization (WHO) states that in developing nations, there are three
million cases of agrochemical poisoning. The prolonged intensive and indiscriminate use of
agrochemicals adversely affected the soil biodiversity, agricultural sustainability, and food safety,
bringing in long-term harmful effects on nutritional security, human and animal health. Most of the
agrochemicals negatively affect soil microbial functions and biochemical processes. The alteration
in diversity and composition of the beneficial microbial community can be unfavorable to plant
growth and development either by reducing nutrient availability or by increasing disease incidence.
Currently, there is a need for qualitative, innovative, and demand-driven research in soil science,
especially in developing countries for facilitating of high-quality eco-friendly research by creating a
conducive and trustworthy work atmosphere, thereby rewarding productivity and merits. Hence,
we reviewed (1) the impact of various agrochemicals on the soil microbial diversity and
environment; (2) the importance of smallholder farmers for sustainable crop protection and
enhancement solutions, and (3) management strategies that serve the scientific community,
policymakers, and land managers in integrating soil enhancement and sustainability practices in
smallholder farming households. The current review provides an improved understanding of
agricultural soil management for food and nutritional security.
Keywords: agrochemicals; pesticide; insecticide; fungicide
Land 2020, 9, 34 2 of 22
1. Introduction
In many developing nations, current agricultural methods follow unsustainable practices which
have resulted in a huge amount of toxic effluents being emitted directly or indirectly into the soil, air,
and water [1]. The advent of nanotechnology and nanomaterials has further complicated the scenario
of soil inputs and their degradation [2,3]. The element of variation in soil properties based on climatic
and geospatial characteristics are also crucial for consideration [4,5]. Currently, various
agrochemicals (i.e., herbicides, fungicides, insecticides, nematicides, molluscicides, rodenticides,
chemical fertilizers are being used non-judiciously [6] which have adversely affected beneficial soil
(micro) biota (Figure 1).
Figure 1. A schematic illustration depicting the response and effects of pesticides on soil microbial
communities and biodiversity.
Any substance used to control, repel, or kill plant or animal life is a pesticide, and the group
includes herbicides, insecticides, and fungicides. There is a constantly increasing demand for
pesticides, and more than 50% of the pesticides used are from Asia (Figure 2). Saint Lucia is at the
top among per hectare usage of pesticides (Figure 3) and China is at the top when it comes to most
pesticide-consuming countries in the world (Figure 4). The increasing global demand for quality
protein-rich food resources for an ever-increasing world population entitles a pressing need for the
development of an ecologically sound strategy for sustaining soil health and advancing food security
without degrading soil biodiversity on a global.
Figure 2. Percentage share of pesticide use by different continent. Source (FAO) [7].
Land 2020, 9, 34 3 of 22
Figure 3. World top ten pesticide consuming countries in kg/ha. Source (FAO) [7].
Figure 4. World top ten pesticide using countries. Source (FAO) [7].
Impact of pesticides on agronomic yield and profit margin makes them a significant component
of modern agricultural practices. However, the indiscriminate use of pesticides leads to the
degradation of soil’s microbial ecosystems [8]. Weeds and insects are the major reducing biotic factors
in agriculture and hamper crop yield, productivity, and resource use efficiency [9]. Therefore,
herbicides (type of pesticide that kills specifically targeted herbs) and insecticides (type of pesticide
that kills specifically targeted insects) are being used indiscriminately for ensuring higher production
by eliminating or suppressing pest population [10]. The United States is first among the top ten
herbicide- and insecticide-using countries in the world (Figures 5 and 6). The cost of labor, choice of
pesticide application, and the promise of swift pest control have made the use of pesticides judicial
or rampant all over the world [11]. These chemical compounds are either applied directly to the soil
strata or as a spray, where drifting sprays and excessive inputs through leaching enters rivers,
streams and other water bodies as agricultural run-offs [12].
Figure 5. World top ten herbicide using countries. Source (FAO) [7].
Land 2020, 9, 34 4 of 22
Figure 6. World top ten insecticide using countries. Source (FAO) [7].
Consequently, the soil receives the bulk of complex agrochemical compounds, several of which
are poisonous to the activity of non-target beneficial soil micro-organisms [13]. More than 95% of the
applied herbicides and 98% of insecticides reach non-target soil micro-organisms than their target
pest, as they are sprayed proportionately across the entire field, irrespective of the affected areas [14].
Hence, of the total quantity of applied pesticides, about 0.1% reaches the target organisms while the
remaining quantity pollutes the soil and environment. This indiscriminate use of pesticides not only
disturbs the soil biodiversity but also adversely affects soil microcosms comprising of soil micro-
fauna in field communities and soil ecosystem [15]. Large quantities of pesticides reaching to the soil
have a direct effect on soil microbiota, which is a biological indicator of soil fertility influencing plant
growth and development [16–18]. Similarly, several studies have reported the impact of numerous
pesticides on subduing soil enzyme activity(s) which affects the nutrient status of soil and include
hydrolyzes, nitrate reductase, urease, oxidoreductases, nitrogenase, and dehydrogenase activities.
Further, biological nitrogen fixation (BNF) and their associated biotransformation (i.e.,
ammonification, nitrification, denitrification, phosphorus solubilization and S-oxidation) are also
affected by pesticide applications [19]. In addition, reduced microbial carbon biomass (MCB) and
functional diversities of many non-target soil microbial populations are affected because of intensive
applications of pesticide in contemporary agriculture [13].
Elaine Ingham, American microbiologist and founder of Soil Foodweb, stated, “If we lose both
bacteria and fungi, then the soil degrades”. Microorganisms in the soil are exclusively important
because they impact soil structure, functions, and fertility [20]. These organisms are primarily
decomposers of organic matter, but also perform many other functions such as provide nitrogen (N),
phosphorus (P), potassium (K), etc., through fixation and mineralization. Thereby helping plants
grow, detoxify harmful chemicals, suppress disease-causing organisms, and produce substances that
may stimulate plant growth. Soil microbes also mineralize the essential plant nutrients in the soil to
improve crop productivity, produce plant hormones that stimulate plant immune system, encourage
growth, and activate stress responses [21]. For example, Rhizobium converts the atmospheric
elemental N into biology. Factors comprising both above and below-ground biodiversity and
population dynamics drive soil health. On a global scale, renewed efforts and focus on management
strategies for food supply and security, nutrition, health, and soil sustainability are mandated for
understanding the impact of agrochemicals on soil microbiota.
The overarching aim of this review is to provide a general overview of the impact of
agrochemicals on soil sustainability and health and to outline some management options that may
be useful to the scientific community, policymakers, and land managers in integrating sustainable
farming practices with organic farming.
2. Methodology
This study represents the existing literature on the use and management of different
agrochemicals. This article tries to improve the understanding of agricultural soil management for
food and nutritional security. The literature review utilized for this paper was mainly qualitative in
nature. We used keyword research in popular databases such as Google Scholar, Scopus and
Land 2020, 9, 34 5 of 22
PubMed. The keywords used were agrochemical, pesticide, herbicide, insecticide, pesticide and soil
biochemistry. Only articles published in English and from reputed journals from individual fields
(Q1 and Q2 ranking journals from individual field based on scimago ranking) were considered. A
sum of 148 publications was included. Major benchmark studies from 2000 to 2019 were selected to
follow the progress in the field across the globe.
3. Herbicides and Soil Microbial Environment
3.1. Impacts of Herbicides on Soil Biota
Herbicides show a reduction in the total microbial population within 7 to 30 days after
application depending on the type of herbicidal molecules [22] and adversely affect the microbial
biodiversity indirectly by altering the physiology or biosynthetic mechanisms [23]. This, in turn,
affects soil enzymatic activity, cellular membrane composition, protein biosynthesis, and the amount
of plant growth regulators (gibberellins synthesis, transportation of Indoleacetic Acid (IAA), ethylene
concentration, etc.) [22]. The application of excessive and higher doses of herbicides has also been
reported to result in the death of many sensitive microbes [22].
The detrimental effects of applied chemical herbicides on soil microbial diversity depend on the
degradability, adsorption and desorption, bioavailability, bioactivity, persistence, concentration, and
toxicity of agrochemicals along with soil factors such as texture, vegetation, tillage system, and
organic matter [18,24]. The reduction in soil microbial functionaries is more under conventional
tillage than in no-till (NT) system. Under conventional till (CT) system, the soil microbial biomass
carbon (MBC) and mycorrhizal colonization decrease after 12 days of application of herbicide
fomesafen and mixtures of fluazifop- butyl + fomesafen [25]. Some microbial communities are more
sensitive to the interaction effect of herbicides with other compounds than the use of a single
herbicide, as is the case with butachlor when applied in combination with cadmium [18]. Other
herbicides in combination with inorganic fertilizers and heavy metals [26–29] suppress the functions
of soil microbes. Following the application, herbicides undergo physical and biochemical
transformations and produce several secondary metabolites which are more lethal or persistent to
non-target microbial communities. This is exemplified by the effect of 2,4-D and its metabolites on
Burkholderiacepacia-a group of gram-negative bacteria [30]. The herbicidal action also depends on the
type of formulation being used in addition to the active ingredient such as surfactant and solvent
[18]. The addition of surfactant polyoxyethylene amine in glyphosate makes herbicide more toxic to
the bacterium as compared to glyphosate acid alone [31]. The use of biochar as a soil amendment
may counter the negative effects of herbicides on soil biota [32].
The soil type can also play a critical role in the herbicidal effect. The effect can be more severe in
coarse-textured soils. For example, Khan et al. (2006) reported severe negative effects of herbicides
on microbial association and vitality of chickpea in sandy clay loam soils [33]. The herbicidal
molecules belonging to the triazines group are more hazardous when applied over a long time due
to their residual effect and persistence in soil [22]. The repeated applications of atrazine can
significantly reduce the intensity of soil microbes [34]. Similarly, atrazine and metolachlor can alter
the biodiversity of different species of actinomycetes and bacteria in soil [34]. Glyphosate, a
nonselective herbicide belonging to organophosphate group, can decrease the activity of phosphate
enzyme up to 98% [35]; inhibit growth and activity of soil biota [16], and have toxic effects on
mycorrhizal fungi when tested under laboratory conditions. Different effects of the herbicidal
application on soil microbial communities, enzymes, and biochemical reactions are presented in
(Table 1).
Table 1. Herbicides and their reported effects on soil microorganisms, enzymes, and biochemical
Herbicides Effects on Microorganism and Associated Process References
2,4-D Adversely affects the activities of Rhizobium sp. [17]
Land 2020, 9, 34 6 of 22
2,4-D Reduces nitrogenase, phosphatase and hydrogen
photoproduction activities of purple non-sulfur bacteria [36]
2,4-D and 2,4,5-T
Adversely affects node-expression disrupting plant
Rhizobium signalling. 2,4-D also reduces fixation by blue-
green algae and nitrifying process impacting
nitrosomonas and Nitrobacter sp.
Agroxone, and
Inhibits activities of Rhizobium phaseoli and Azotobacter
vinelandii (most sensitive) [17]
2,4-D, Bromoxynil,
and Methomyl Reduces CH4 oxidation to CO2 [38]
Bensulfuron methyl
and Metsulfuron-
Decreases N-mineralization [39]
Prometryn, Simazine,
and Terbutryn
Inhibits N-fixation and decreases the number of nodules
and N content overall [40]
Adversely impacts nitrosomonas, Nitrobacter, urea
hydrolyzing bacteria, nitrate reductase activity and
growth of actinomycetes and fungi
Linuron, Terbutryn,
Adversely impacts nitrogenase activity and nodulation at
the pre-emergence application [33]
Glyphosate Suppresses phosphatase activity [35]
Glyphosate Reduces the growth and activity of azotobacter [16]
Metribuzin At lower doses, no effects on AM fungi in maize and
barley are observed [42]
3.2. Impact of Herbicides on N-Fixing Microbes
Several herbicides can alter the symbiotic association between legume plants and rhizobacteria
and hinder the vital processes of N-fixation [40,43]. Herbicides may influence the nodulation and
consequently the BNF in legumes either by disturbing rhizobacterial infection process or by affecting
root fibers of the plants where infection and node formation occur. They may also affect the
phytochemical signaling of Rhizobium needed for coordination and regulation of the key processes in
BNF [18]. Some herbicides affect the morphology of the cell, resulting in the formation of pleomorphic
cells [18]. Herbicides can reduce root nodulation, bacteroids, dry plant matter, nitrogenase activity
and adenosine triphosphate (ATP) synthesis of Rhizobium and thus symbiotic N-fixation [22]. Use of
herbicides in soybean can suppress the growth and activity of Bradyrhizobium. The growth of
Bradyrhizobium japonicum is abridged due to the application of herbicides in soybean in vitro cultures,
while nodulation is affected under controlled greenhouse conditions [44]. However, the growth of B.
japonicum is not affected by chlorimuron ethyl in pure cultures even at 150 times higher concentration
than the recommended field rates [45]. The commonly used triazines (i.e., terbutryn, simazine,
prometryn, and bentazone) reduces the rhizobial functionaries at concentrations more than the
recommended rate [40]. On the contrary, herbicides such as sethoxydim, alachlor, fluazifop-butyl,
and metolachlor had no detrimental effect on BNF and soybean yields at the recommended field
rates. However, the non-selective herbicides paraquat and glyphosate (due to the presence of
ethylamine formulation) [46] can reduce the N-fixation in soybean. Herbicide pendimethalin at 0.5–
1.0 kg/ha can slow down the process of Rhizobium symbiosis in crop plants [47]. The commonly used
herbicide 2,4-D tends to reduce the growth and activity of blue-green algae (BGA), inhibits
nitrification, and the BNF process by affecting the activity of Rhizobium sp. in beans. The residues of
2,4-D are found in cell wall and cytosol of Rhizobium in significant amounts confirming its impact on
rhizobacterial propagation [17].
Land 2020, 9, 34 7 of 22
Azotobacter is anaerobic, free-living soil microorganism that plays an important role in N-cycling
by fixing nitrogen. It is highly sensitive to herbicides, even for a short exposure of 7–14 days [22]. The
extent of inhibition of activity, population, growth, and development of Azotobacter depends on the
kind as well as the dosage of herbicidal molecules used [46]. In the field of soybean and sunflower
treated with prometryne, the biological activity of Azotobacter and some other bacteria was strongly
reduced after 28 days of herbicide application [48]. Herbicides 2,4-D, atranex, and agroxone inhibited
the occurrence of Rhizobium phaseoli and Azotobacter vinelandii, and their population further decreased
with increase in herbicide concentration. Similarly, in sugarbeet, dimethenamid and metolachlor
application significantly reduced Azotobacter’s population by 33%–50% at the rate of 1.7 l/ha [48], use
of dimethenamide by 2% and 18% at the rate of 1.6 l/ha compared with 1.4 l/ha and the blend of
flumetsulam + trifluralin by 2% at the rate of 2 l/ha compared with 1.7 l/ha as recommended [48].
3.3. Impact of Herbicides on Arbuscular Mycorrhizal Fungi
Mycorrhizas are symbiotic associations between fungi and roots of higher plants that enhance
the uptake of nutrients, especially P, nitrate (NO3), and ammonium (NH4), and improve soil
aggregate stability [49]. The herbicides oryzalin, trifluralin, and oxadiazon have a deleterious effect
on spore germination and propagation of mycorrhizal species [50]. In contrast, oxyfluorfen and
oxadiazon stimulate the microbial population significantly and can enhance the P availability in rice
[51]. Glyphosate significantly decreases root mycorrhization by 40%, soil arbuscular mycorrhizal
fungal (AMF) spore biomass, vesicles, and propagules under greenhouse conditions [52].
Glyphosate can directly influence the active metabolite production in the plant with negative
impacts on root colonization of AMF [53], and indirectly affect the intra-radical mycelium growth
and arbuscular formation which regulates the AMF abundance [52]. In contrast, Pasaribu et al.
(2013) [50] did not find any significant effects of glyphosate on AMF (Glomus mosseae), and thus the P
inflow through mycorrhizal hyphae was significantly increased with the application. Pasaribu and
colleagues also reported that increasing rates of alachlor application significantly reduced the
numbers of spores, total and active infection intensity of internal hyphae of vesicular–arbuscular
The adverse impacts of herbicides prometryn and acetochlor on AMF and symbiosis at
increasing rates from 0.1 to 10 mg/L are widely known, with prometryn being more toxic than
acetochlor [49,50]. Sharma and Buyer (2015) [54] observed the adverse effects of herbicides on AMF
live-biomass in terms of AM signature fatty acids 16:1ω5 phospholipid fatty acid (PLFA) and 16:1ω5
neutral lipid fatty acid (NLFA) representing hyphal biomass and spore population in soil
respectively, as a measure of AM propagation and survivability. Zaller et al. (2014) [52] observed the
effects of Roundup (glyphosate) application on hyphae (i.e., amount of 16:1ω5 PLFA) and spore (i.e.,
amount of 16:1ω5 NLFA) biomass in the soil and found that spore biomass declined with herbicide
application. Similar observations have been reported by Druille et al. (2013) [55], who showed that
the spore germination is affected even at the lowest dose of glyphosate. While evaluating several
biological pesticides along with chemical fungicides, Ipsilantis et al. (2012) [56] observed that
application of pyrethrum, terpenes, and spinosad did not significantly affect the structure and root
colonization ability of the AM fungal community. However, pots treated with carbendazim
completely hampered mycorrhizal colonization. Gupta et al. (2011) [57] suggested that herbicidal
application at higher concentrations should be resorted to only after careful consideration. While
evaluating the impact of metribuzin herbicide on three species of AMF in maize and barley, Makarian
et al. (2016) [42] reported that inoculation of AMF considerably improved the growth and chlorophyll
content of barley and maize at lower herbicide concentrations (175 g a.i. ha−1) compared to non-
inoculated treatments. Thus, it suggested that mycorrhizal fungi can alleviate crop stress under lower
doses of metribuzin through increase in plant growth and advocated for avoiding the administration
of higher doses. On the other hand, Sharma and Adholeya (2005) [54] found a positive effect of
nematicide-carbofuran 3G (furadan) when applied in maize pot cultures and suggested their uses for
cleaner maintenance of pot cultures. Thus, the effects of herbicides on AMF are case-dependent, and
factors such as soil mineral composition, type of host, plant fitness and the nature of plant–fungal
Land 2020, 9, 34 8 of 22
symbiotic interactions regarding reciprocal rewards may play a key role in determining the overall
cause and effect [58]. It has also been reported that phenotypic plasticity governed by nutrient cycling
and environmental factors, and plant–fungal phospholipid metabolism in AMS may lead to observed
trait variations among different plant and AMF combinations in either agricultural or controlled
environmental settings [59].
3.4. Impact of Herbicides on Soil Biochemical and Enzymatic Environment
Herbicides reduce several beneficial biochemical processes governed by soil microbes and
enzymatic reactions that play a crucial role in maintaining or improving soil health [60]. Biochemical
processes driven by soil microbes include mineralization, and associated bio-transformations like
nutrient dynamics (nitrification, denitrification, and ammonification), redox reactions,
methanogenesis, etc., are affected by exposure to herbicides [61]. The biochemical process of
denitrification and nitrification are diminished in soils treated with prosulfuron even after N
fertilization [60]. Herbicides also influence the soil enzymatic activities that influence ‘‘biological
index’’ of soil fertility and biological functions in the soil profile [62]. Acetochlor and its derivatives
are toxic to bacteria (i.e., fluorescens, Bacillus. subtilis, and Mycobacterium. phlei) that are involved in N
transformations [63]. The herbicide, atrazine and simazine can completely arrest the growth, and
biological action of Xanthobacter autotrophic when applied at the rate of 10 mg/L [64]. The herbicides
alachlor and atrazine negatively affect the functioning of bacteria, those are needed for
ammonification, and soil dehydrogenase activities at applications higher than the field recommended
dose [65]. The impact on microbial activities varies with the mode of the herbicide application. For
example, glyphosate applied in bunds can significantly diminish enzymatic activity but not when
applied as granules. The herbicides atrazine and metolachlor can reduce the activity of invertase and
dehydrogenase enzymes [35], respectively. However, chlorimuron-ethyl and furadan may enhance
the activity of both these enzymes by 14%–18% and 13%–21%, respectively [66,67].
4. Fungicides and Soil Microbial Environment
4.1. Impact of Fungicides on N-Fixing and Growth-Promoting Microbes
Most copper (Cu) based fungicides have a deleterious effect on the population of N-fixing
bacteria [68]. Fungicidal residues, for example, apron, arrest, captan, tend to remain in soil reacting
with living organisms and affecting the N-fixation in legume-Rhizobium association [69]. Both
mancozeb and chlorothalonil can decrease the process of nitrification and denitrification at an
incubation period of ≥48 h [60]. The negative impact of the long-term application of organomercurial
Verdean on cellulolytic fungal species has also been reported [70]. Further, application of triarimol
and captan can decrease the frequency of Aspergillus species responsible for plant growth and
development. Carbendazim is moderately toxic to Pseudomonas fluorescens and Bacillus subtilis while
being highly toxic to Trichoderma harzianum, a potent biocontrol agent active against soil-borne fungal
phytopathogens (i.e., Fusarium, Pythium, and Rhizoctonia) on soybean, potato, cotton and other crops
[63]. The impact of fungicides such as chlorothalonil and azoxystrobin on soil microbial activities, has
long been recognized with negative effects on the biocontrol agents itself as in Fusarium wilt [71]. On
the other hand, the inhibitory effect of fungicide applications on the activity of certain fungi has led
to a fast flush of bacterial activity as well [13].
4.2. Impacts of Fungicides on Soil Microbiota
Several studies have reported the harmful effects on soil microbial growth, survival, and activity
[72]. Fungicide bavistin has an inhibitory effect on several soil microbial populations, but the impact
is non-significant [57]. AMF can be sensitive to some molecules of fungicides but not to all [73].
Benzoyl is responsible for the long-term reduction in mycorrhizal associations [74] with many
fungicides being toxic to hyphal growth and thus root colonization of AMF associations of pea [72].
Emisan (holding 6% 2-methoxyethylmercury chloride) and carbendazim (benzimidazole fungicide
and a metabolite of benomyl) both have a damaging effect on AMF in groundnut. However,
Land 2020, 9, 34 9 of 22
applications of Cu can provide a stimulus to mycorrhizae in groundnut. Applications of metalaxyl
favor AM colonization in roots of soybeans and maize [66]. Murillo-Williams and Pedersen (2008)
[75] reported that under non-fumigated soil conditions, seed-applied fungicides in combination with
fludioxonil favors AM colonization due to a reduced competition from aggressive pathogens like
Rhizoctonia spp., an organism that is the target of this fungicide. The impact of a wide range of
fungicides on beneficial soil microbiota is depicted in Table 2.
Table 2. Fungicides and their impacts on beneficial processes of soil microbiota.
Fungicides Effects on Microorganism and Associated Process References
Apron, Arrest, and
Captan Reduces viable counts of Rhizobium ciceri [69]
Benomyl Impacts mycorrhizal associations and nitrifying bacteria [76]
Benomyl, Mancozeb Arrests activity of dehydrogenase, urease, and
phosphatase enzymes [77]
Inhibits aerobic N-fixing, nitrifying, denitrifying bacteria,
nitrogenase activity, phosphate solubilization and other
Captan and Thiram Decreases cell growth and nitrogenase activity in
Azospirillum brasilenseeven at a lower dose of 10 mg/L [78]
Captan and
Carbendazim Decreases nitrogenase enzyme activity [36]
Captan, Carboxin,
Inhibits the activity of bacteria responsible for
denitrification [79]
Carbendazin and
Inhibits nodulation in legumes and thus N-fixation
process [80]
Chlorothalonil Effects bacteria associated with nitrogen cycling [76]
Azoxystro Effects biocontrol agent(s) used against Fusarium wilt [71]
Copper fungicides Decreases population of bacteria, cellulolytic fungal
species and streptomycetes in sandy soil [70]
Dimethomorph Inhibits nitrification and ammonification process in
sandy soils [81]
Dinocap Inhibits the activity of ammonifying bacteria [82]
Dithianon Destrucs bacterial diversity in soil [83]
Fenpropimorph Slows down bacterial activity in wetlands [79]
Fludioxonil Toxic to algal activities [84]
Funaben, Baytan,
Inhibits nitrogenase activity of methylotrophic bacteria at
a higher dose [85]
Hexaconazole Impacts bacteria involved in N cycling [86]
Mancozeb Impacts on bacteria involved in N & C cycle in soil [82]
Chlorothalonil, Metal
Reduces nitrification process [60]
Metalaxyl Reduces urease activity continuously while phosphatase
activity seems stimulated but then reduces [87]
Metalaxyl Disturbs activity of ammonifying and nitrifying bacteria
Oxytetracycline Acts as bactericide [88]
Pencycuron Short-term impact on metabolically active soil bacteria [89]
Propiconazole May retard plant growth-promoting effects of
Azospirillum brasilense on its host plant [90]
Triadimefon Deleterious to long-term soil bacterial community [91]
Land 2020, 9, 34 10 of 22
Triarimol and Captan Reduces frequency of Aspergillus sp. [92]
4.3. Impact of Fungicides on Soil Enzymes and Biochemical Environments
Several biochemical processes in soil are closely linked with enzymatic activities which are
adversely affected by residues and toxic elements left after application of fungicides [93]. Fungicides
benomyl, mancozeb, and tridemorph inhibit the soil enzymatic activity of dehydrogenase, urease,
and phosphatase [77]. Activities of phosphomonoesterase and urease enzymes are also inhibited in
soils treated with captan, trifloxystrobin, and thiram fungicides [94,95]. Yet, captan and thiram are
classified as soil and seed protectant fungicides, respectively. However, the fungicide ridomil has a
non-significant impact on the activity of a phosphatase enzyme [65]. These enzymes may be protected
from degradation by adsorption on clays or humic substances in soil [18,73]. The smaller the size of
the clay particle, the greater is the protection against the added fungicides [96]. The synthesis of
amino acids of certain bacteria is repressed by some glucopyranosyl antibiotic fungicides [93,97,98].
The use of Cuin combination with mefenoxam can disturb soil microbial diversity as determined by
structural and metabolic profiling. The population of ammonium oxidizing bacteria is decreased by
the application of mefenoxam and mefenoxamp Cu fungicides after 60 days of application [65].
5. Insecticides and Soil Microbial Environment
5.1. Impact of Insecticides on N-Fixing and Another Growth-Promoting Microorganism
The applied insecticides affect the growth, survival, and working capacity of symbiotic rhizobial
association with roots of legume plants resulting in dwindled atmospheric N-fixation [80]. The
antagonistic interaction between the applied insecticides and symbiotic N-fixers differ with the
specific chemical group of insecticide and the specific N-fixer group. However, the field
recommended doses of these chemicals had little effect on symbiotic N-fixing bacteria [66]. The
growth and population of Azotobacter are significantly inhibited because of phosphamidon,
malathion, fenthion, methyl phosphorothioate, and parathion [99]. Nonetheless, insecticides like
carbofuran, phorate, and disulfoton have little effect on the numbers of Azotobacter in the soil.
Dinoseb, when used as an insecticide, inhibits the nitrogenase activity by 60%, 90% and 100% at 3
ppm, 6 ppm, 9 ppm, respectively [80]. While chlorpyrifos and their derivatives affect the biological
activities of Pseudomonas fluorescences, Bacillus subtilis, Mycobacterium phlei, Trichoderma harzianum,
Penicillium expansum, and Fusarium oxysporum [63]. Monocrotophos and cypermethrin have a
negative impact on the population of soil bacteria, whereas fenvalerate has a slight effect [100].
Several other insecticides (i.e., chlorfluazuron, cypermethrin and phoxim) also has an inhibitory
effect on soil microbes even at field recommended doses/concentrations [101]. The application of
insecticides chlorpyrifos, imidacloprid, cypermethrin, endosulfan and carbofuran under field
conditions causes considerable variation in soil bacterial populations [102]. Among the applied
insecticides, chlorpyrifos has the most destructive effect on soil bacterial diversity. However, the
insecticides monochrotophos, quinalphos, and cypermethrin show a positive effect at lower and
antagonistic effects at higher doses [103]. Cypermethrin and monocrotophos are more harmful to soil
bacteria and other microbes, whereas fenvalerate is less harmful [67].
5.2. Influence of Insecticides on Soil Biochemistry
The residues of insecticides, when applied at field-recommended rates, do not cause any
harmful influence on the nitrification [80]. However, it is the prolonged use and the amounts of such
insecticides that cause concerns. Nevertheless, at higher rates, it inhibits the process of nitrification
and microbes involved in it [103]. For example, the biochemical process of nitrification and
denitrification are reduced in soils contaminated with monocrotophos, lindane, dichlorvos,
endosulfan, malathion, and chlorpyrifos when applied at concentrations of 0.02 to 10 times that of
field recommended dose [104]. Insecticides have an adverse impact on soil microbes that are
important to N transformation in soils, and the degree/extent of toxicity may vary based on the type
Land 2020, 9, 34 11 of 22
and group of insecticide [105]. Further, the ammonification is less sensitive to insecticide residues.
However, at higher doses, the ammonification process is often reduced [81]. Some insecticides have
a neutral effect on ammonification (e.g., superacids (25 and 500 g/ha) and nuvacron (100 and 600
g/ha) did not affect the ammonification process but is significantly reduced at higher concentrations
of 1000 g/ha and 750 g/ha, respectively under controlled laboratory conditions [60].
5.3. Impacts of Insecticides on Agrobiology
There is a significant impact of pesticide contamination in soil ecosystem [106]. The repeated use
of such complex chemicals (fertilizers, weedicides, insecticides, etc.) inevitably kill the microbial life
that is invaluable for the healthy soil ecosystem [107]. Soil-dwelling microbes can be genetically
modified using insecticides in a manner that is no longer helpful to the soil ecosystem and may
eventually become resistant to the chemicals, intended to exterminate them. Insecticides have a
higher effect on soil microbes compared to herbicides, albeit less than that of fungicides [12]. Some
insecticides are detrimental to the growth and survival of beneficial microbes, but others may have
stimulating or no effects [108]. For example, insecticides of the carbamate group (e.g., carbofuran,
methiocarb, and carbaryl) have a wide range of negative impact on soil microbial environment [35]
and enzymatic activity [109]. Similarly, insecticides belonging to the chemical group of
organophosphates (i.e., dimethoate, diazinon, chlorpyrifos, quinalphos, and malathion) inhibit the
growth and population of soil bacteria, fungi [99], and enzymes [110]. Arsenic, DDT, and lindane also
have a negative effect on the microbial biomass [110], microbial processes, and enzymatic activities
[68] that are attributable to their long-standing residual effect and persistence in soil. The effects of
different insecticides on the soil micro-flora and fauna that are linked with nutrient cycling are
presented in Table 3.
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Table 3. Impact of insecticides on soil microorganisms, enzymes, and biochemical reactions.
Insecticide Effects on Microorganism and Associated Process References
Amitraz, Aztec, Cyfluthrin, Imidachlor, and
Tebupirimphos Reduces activities of urease and phosphatase enzymes for a week [111]
Arsenic, DDT, and Lindane Decreases microbial biomass and microbial and enzymatic activities as a result of longer
persistence in soil [110]
Bensulfuron methyl and Metsulfuron-methyl Reduces soil microbial biomass [112]
Carbamate insecticides Inhibits several soil microorganisms, enzymes and nitrogenase activity of
Carbendazim, Imazetapir, Thiram Decreases nitrogenase activity in
. R.
, Bradyrhizobium
Sinorhizobium melilot in pot cultures as well as in field conditions [80]
Carbofuran, Ethion, and Hexaconazole Inhibits nitrogenase activity of
Anabaena doliolum
by 38% within 48 h of application [109]
Chlorinated hydrocarbons Inhibits methanogenesis [61]
Chlorpyrifos, Dichlorvos, Phorate, Monocrotophos,
Methyl parathion, Cypermethrin, Fenvalerate, Methomyl
and Quinalphos
Increases phosphatase activity initially and later reduces gradually. Phorate reduces the total
bacterial population and N-fixing bacteria [67]
Chlorpyrifos, Profenofos, Pyrethrins, and
Reduces the population of aerobic N-fixing, nitrifying, denitrifying bacteria and several
fungi. Profenofos and Pyrethrins decreases the activity of urease enzyme and nitrate
Chlorpyrifos, Quinalphos Reduces ammonification process [67]
Cyfluthrin, Fenpropimorph, and Imidacloprid Decreases nitrification and denitrification process, and stimulates sulphur oxidation [111]
Diazinon and Imidacloprid Inhibits urease-producing bacterium (
) [113]
Lindane, Malathion, Diazinon, and Imidacloprid
Lindane inhibit state of nitrification, N-availability, P-solubilization and activity of
phosphomonoesterase enzyme while the opposite effect is observed in the case of Diazinon
and Imidacloprid
Metalaxyl and Mefenoxam Decreases nitrogen-fixing bacteria and microbial biomass [66]
Methamidophos Reduces microbial biomass by 41%–83% [13]
Neemix-4E Reduces urease enzyme activity [62]
Organophosphate insecticide Impacts the activity of soil enzymes, several beneficial soil bacteria, and fungal population
and reduces N-mineralization rate [99]
Pentachlorophenol Reduces nitrification [114]
Quinalphos Reduces activity of enzyme phosphomonoesterase which recovers later [115]
Validamycin Negatively effects phosphatase and urease enzyme which improves later [116]
Land 2020, 9, 34 13 of 22
6. Management Options
Interestingly, since the advent of pesticides and its related derivatives, studies on their harmful
effects have also been conducted for over a century, and many legislative actions and pesticide-
related incidents have been documented [99]. The advent of fast and reliable analytical techniques
has paved the way for greater understanding of the long-term effects of pesticides and related
hazards posed to soil and natural ecosystems. Hence, with the ever-growing knowledge on pesticide-
related health and environmental issues, new legislative actions are being amended or modified at a
rapid pace suggesting major improvements in smarter and efficient pest control [117]. Integrated
management of pesticides, its applications, and its residues have been proposed as an effective
strategy for minimizing the harmful effects [118]. The biological control of pests has been at the
forefront of many of the latest environmentally friendly approaches to tackling the menace of
pesticide pollution. Some of the key effective management strategies are discussed below.
6.1. Biopesticides
Biopesticides are natural substances that can be derived from micro-organisms (microbial
pesticides), plant-derived that contain added genetic material (plant-incorporated protectants-PIPs)
and other naturally occurring products (biochemical pesticides) that offer pest control [119].
Biopesticides or biological pesticides play a significant part in pest management approaches for better
and eco-friendly alternatives to chemical pesticides while minimizing pollution and contamination
of soils and without compromising on soil microbial communities. Biopesticides ensure good soil
health and environmental sustainability for eco-friendly agricultural production. Introducing
beneficial microorganisms in any living system need to have a characteristic dominant role over
disease-causing microbial populations. Mostly, these bio-products improve nutritional uptake
efficiency of plants and increase crop performance, when applied directly to soils or as foliar
applications. While biopesticides made from pathogenic microorganisms are specific to a target pest,
biopesticides from beneficial interactors offer a better and ecologically solution. Furthermore,
biopesticides do not harm the environment and soil microbes as compared to conventional chemical
compounds [120].
The most commonly used biopesticides include Bacillus thuringiensis (Bt), Baculoviruses,
Trichoderma, Azadirachta indica. PIPs, for example, Bacillus thuringiensis is the most globally popular,
which is being used against moth larvae on plants, and the strains are made specifically for the larvae
of mosquitoes and flies [121]. Important among microbial biopesticides are: (1) the Baculo viruses to
target specific viruses which exterminates the disease-causing to lepidopterous insects of cotton, rice,
and vegetables [122], (2) Trichoderma and Trichoderma-based products being effective against soil-
borne diseases (i.e., root rot) and control of rots and wilts in dryland crops such as black gram (Vigna
mungo), groundnut (Arachis hypogaea), chickpea (Cicer arietinum) and green gram (Vigna radiate) [120]
and (3) the entomopathogenic nematodes (EPNs) of the genera Heterorhabditis sp. and the Steinernema
sp. as potential agents against insect-pests of the genera Diptera, Coleoptera, Lepidoptera and
Orthoptera and to kill many soil-dwelling insect-pests within 24–48 hours [123]. The efficacy of EPN
as a biopesticide is affected by nematode species, strain, production and storage conditions, and
persistence in the habitat and susceptibility of target insect pests [123]. In comparison, several other
bio-control agents take a few days or weeks to kill the target insect pest. EPNs are safe to most non-
target beneficial soil organisms, and the ecosystem, easy to apply and are compatible with most
agricultural chemical compounds. However, the cost of production, limited shelf-life and
environmental conditions (moisture, temperature, UV sensitivity, etc.) are some of the major
disadvantages in the broader application of EPNs [119].
6.2. Plant-Based Products
The active secretion of specific compounds from plant roots either stimulates or suppress the
diverse soil microbial community [124]. For example, the secretion of strigolactones (a plant
sesquiterpene) promotes symbiotic interactions by attracting mycorrhizal fungi of the order
Land 2020, 9, 34 14 of 22
Glomeromycota [125]. The legumes release flavonoids which function as signaling molecules inviting
N-fixing bacteria in the rhizospheric zone for the establishment of rhizobial symbioses [126,127]. The
plant growth-promoting rhizobacteria (PGPR) also benefits other soil microbes through the release
of organic acids, for example, tomato roots release citric and fumaric acids which attract Pseudomonas
fluorescence [128]. Neem cake oil is another good example of biopesticides as it offers the essential
nutrition for soil microorganisms, and improves soil physicochemical properties besides controlling
a wide range of pests [129]. Further, the usefulness of the botanical insecticide, azadirachtin (an
allelochemical from neem) as an effective anti-fungal [130] and anti-microbial [131] compound has
long been recognized. The effect of 10% azadirachtin granules (alcoholic extract of neem seed kernel
mixed with china clay) on the microbial communities and their enzymatic activities suggested that
azadirachtin at all doses exerts a suppressive effect [129].
Nonetheless, the negative impacts of neem (seed cake) are also reported. Elnasikh et al.(2011)
[132] stated that neem seed cake impacts the population of Bactoderma, Nocardia, fungi, and the
inorganic N-users, including nitrifying bacteria negatively. However, neem cake impacts positively
on the population of actinomycetes. The neem seed cake has the properties of inhibitors of
nitrification and pesticide degradation [132]. In contrast, azadirachtin, neem extracts and their
products (i.e., Neemix 4.5E and Eneem 3G) can impart low short-term toxicity on mycorrhizal Glomus
intraradices [130]. Ipsilantis et al. (2012) [56] investigated the effect of bio-pesticides (pyrethrum,
azadirachtin, terpens, and spinosad) along with synthetic fungicide carbendazim on exogenous AMF
inoculum in pots and on indigenous AMF in field conditions. They reported that pyrethrum,
terpenes, and spinosad did not significantly affect the structure and colonization ability of the AM
fungi. However, the application of azadirachtin in pots caused selective inhibition of Glomus
etunicatum strain and carbendazim completely hampered mycorrhizal colonization and the
community structure of indigenous AMF [56]. This apparent disparity observed in neem, and various
neem extract application may be attributed to the disturbance in the natural balance of some soil
microbes and AMF. Several environmental, host, and symbiotic factors play a role in the observed
trait variation among AMF [133,134]. The effect of neem oil cake can be similar to that of the
azadirachtin in stimulating the population of Azotobacter [135]. Nitrosomonas, Nitrobacter, and
Nitrosococcus are strongly affected by azadirachtin and any neem product or active ingredients
present in neem seed, that is, medicines (epinimbin, Nimbin, salannin, nimin, nimbidin) at
recommended as well as higher rates [130]. In general, the observed effects are pronounced at lower
temperatures and low soil moisture levels [129]. The inhibitory influences of neem on nitrifying
bacteria are also well documented by Kiran and Patra (2003) [135]. The application of neem seed
kernel extract inhibits nitrification during 7 to 21 days of application, and this inhibition is more in
acid soils and less in sodic and normal soils. The same trend is observed in activities of urease enzyme
[136]. However, the activity of urease enzyme is affected temporarily by Neemix- a 4E application
which ranges from being neither severe nor extended enough to be considered harmful to the soil
microbes [62]. Similarly, azadirachtin granules do not affect the soil dehydrogenase activity in any
way even at higher doses, while the activities of phosphatase and dehydrogenase enzymes are
considerably improved with the application of botanical pesticide at the recommended dose [137].
The increase in phosphatase enzyme activity is attributed to the effect of azadirachtin on the soil
microorganisms, subsequent decomposition and release of the phosphates from the dead microbial
biomass [129].
6.3. Microbial-Based-Products
Microbial inoculation for plant growth and soil health promotion has been at the forefront of
many new and exciting innovations in sustainable crop production endeavors [59]. Correspondingly,
seed and soil inoculations of beneficial microorganisms have gained tremendous interest in recent
years with the advent of a group of bacteria called the plant growth-promoting bacteria (PGPR) [138]
harboring several polyfunctional abilities. Microbial biopesticides, not only enhance soil fertility but
are also environmentally friendly and safe for crops. The percentage of soil MBC is significantly
enhanced overtime in biopesticide treated soils (like Folicon, Bacillus subtilis, Pseudomonas florescent,
Land 2020, 9, 34 15 of 22
Paeciliomyces lilacinusand Beauveria bassiana) compared with that under control. The maximum
increment (1.46%) is noticed with Paeciliomyces lilacinus, and the lowest (0.98%) with Bacillus subtilis
treated soils over a period of 2 to 6 weeks of treatment [139]. Similarly, seed dressing with
Pseudomonas at 3 g/kg results in increase in number of fungal (12.27 × 104 CFU per g soil),
actinomycetes (11.4 × 105 CFU per g soil) and Bradyrhizobium japonicum population (27.7 to 35.2 × 104
CFU per g soil) over that in control at the time of harvest of oilseeds [140]. Genetically engineered
plants have considerable effects on non-target soil microorganisms, soil enzymes and root
colonization of G. mosseae [137]. While some reports indicate that Bt cotton may have positive effects
on soil-flora and fauna, others have reported negative effects [141]. The effects caused by transgenic
plants on soil microbes are temporary and occur at a particular stage of crop growth [142]. The
transgene proteins in transgenic plants produce the chemical substances that are potentially lethal to
beneficial soil micro-fauna and flora, including mycorrhizal fungi that are involved in soil organic
matter [143]. For example, the crystal toxin protein produced by leaves, stems, and roots of transgenic
plants expressing the gene of Bt is one of the most common transgene proteins that release large
quantities of toxins into the soil ecosystem. It enters the soil through biomass incorporation, death,
and turnover of sloughed root cells and root exudates [143]. However, measurements of Bt corn
uptake and insecticide use in the US indicate that the overall pesticide use dropped 0.6% per year
between 1980 and 2007. It is yet to be investigated further whether an increase in pesticide use is
warranted underdevelopment of some resistant insects [144].
6.4. Transgenic Herbicide-Resistant Crops
The root exudates of the genetically modified herbicide-resistant crops in the soil environment
interact either positively or negatively with living organisms that inhabit in soil [142]. The genetically
transformed glyphosate-resistant rapeseed containing the pat’ gene (Brassica napus) influences soil
microorganisms such as Bacillus, Micrococcus, Variovarax, Flavobacterium, and Pseudomonas [137]. The
populations of these microbes are scarcely observed on the root surface of transgenic rapeseed
cultivars compared to that of non-transgenic cultivars. The group of root-endophytic bacteria of the
transgenic cultivar has lesser diversity than that of non-transgenic cultivar [145]. In contrast, the
transgenic cultivars of maize and sugar beet containing the same pat gene have a non-significant
influence on the diversity of rhizospheric bacteria [146]. Interestingly, glyphosate-resistant oilseed
rape has considerable effects on the communities of soil biota, whereas glufosinate resistant oilseed
rape, sugar beet, and maize show non-significant effects. This trend is present may be due to the
different chemical makeup of herbicides and soil types that causes varied effects on microbial
populations or due to the different root exudates altered by the insertion of different transgenes in
transgenic plants [143]. Powell et al. (2007) [44] evaluated nine soybean cultivars (six were genetically
modified) to express transgenic cp4-epsps, in the presence of AMF and Bradyrhizobium japonicum and
reported differences in nodule numbers, biomass and mycorrhizal colonization among cultivars.
7. Conclusions
The mandate for agriculture development is to feed and provide adequate nutrition and surplus
to the mounting human population without compromising on ecology and environment of the
biosphere. Pesticides and their use are considered as magic bullets in developing nations. Pesticides
cause serious hazards to soil environment and human health because a lot of pesticides and their
derivatives remain in the soil system for a considerable period. Most pesticides negatively affect the
biological functionaries of microbes, their diversity, composition, and biochemical processes.
Pesticides cause imbalance of soil fertility which directly affects crop yield.
Judicious and discriminate use of pesticides is critical because most harmful effects are caused
by the application doses that exceed the recommended rates. The education of farmers, distributors,
industry, policymakers, and other stakeholders in the discriminate use of pesticide is critical to
reducing the adverse effects on humans and the environment. Well-designed experiments are needed
on the long-term effect of pesticides on microbial communities and their long-term eco-toxicological
effects in the soil environment.
Land 2020, 9, 34 16 of 22
The work was supported by the project of Technology Agency of the Czech
Republic TH03030319: “Promoting the functional diversity of soil organisms by applying classical
and modified stable organic matter while preserving the soil's production properties”.
Author Contributions: Conceptualization, R.S.M., S.K. and V.V.; methodology, M.K.J., G.S.Y. and M.P.S.; formal
analysis, M.B., T.D., and V.P.; resources, M.B., C.J.; data curation, T.M.; writing—original draft preparation,
R.S.M. and S.K.; writing—review and editing, R.D. and S.I.P.; supervision, R.L.; All authors have read and agreed
to the published version of the manuscript.
Funding: This research received no external funding.
Conflicts of Interest: The authors declare no conflict of interest.
1. Yáñ ez, L.; Ortiz, D.; Calderón, J.; Batres, L.; Carrizales, L.; Mejía, J.; Martínez, L.; García-Nieto, E.; Díaz-
Barriga, F. Overview of human health and chemical mixtures: Problems facing developing countries.
Environ. Health Perspect. 2002, 110, 901–909.
2. Mishra, P.K.; Giagli, K.; Tsalagkas, D.; Mishra, H.; Talegaonkar, S.; Gryc, V.; Wimmer, R. Changing Face of
Wood Science in Modern Era: Contribution of Nanotechnology. Recent Pat. Nanotechnol. 2018, 12, 13–21.
3. Mishra, P.K.; Gregor, T.; Wimmer, R. Utilising Brewer’s Spent Grain as a Source of Cellulose Nanofibres
Following Separation of Protein-based Biomass. BioResources 2017, 12, 107–116.
4. Marfo, T.D.; Datta, R.; Pathan, S.I.; Vranová, V. Ecotone Dynamics and Stability from Soil Scientific Point
of View. Diversity 2019, 11, 53.
5. Danso Marfo, T.; Datta, R.; Vranová, V.; Ekielski, A. Ecotone Dynamics and Stability from Soil Perspective:
Forest-Agriculture Land Transition. Agriculture 2019, 9, 228.
6. Meena, H.; Meena, R.S.; Rajput, B.S.; Kumar, S. Response of bio-regulators to morphology and yield of
clusterbean [Cyamopsis tetragonoloba (L.) Taub.] under different sowing environments. J. Appl. Nat. Sci.
2016, 8, 715–718.
7. Food and Agriculture Organization of the United Nations. FAOSTAT Statistical Database; FAO: Rome, Italy,
8. Önder, M.; Ceyhan, E.; Kahraman, A. Effects of Agricultural Practices on Environment. Biol. Environ. Chem.
2011, 24, 28–32.
9. Oliveira, C.M.; Auad, A.M.; Mendes, S.M.; Frizzas, M.R. Crop losses and the economic impact of insect
pests on Brazilian agriculture. Crop Prot. 2014, 56, 50–54.
10. Meena, R.S.; Bohra, J.S.; Singh, S.P.; Meena, V.S.; Verma, J.P.; Verma, S.K.; Sihag, S.K. Towards the prime
response of manure to enhance nutrient use efficiency and soil sustainability a current need: A book review.
J. Clean. Prod. 2016, 112, 1258–1260.
11. Bahadur, S.; Verma, S.K.; Prasad, S.K.; Madane, A.J.; Maurya, S.P.; Gaurav Verma, V.K.; Sihag, S.K. Eco-
friendly weed management for sustainable crop production-A review. J. Crop Weed 2015, 11, 181–189.
12. Aktar, W.; Sengupta, D.; Chowdhury, A. Impact of pesticides use in agriculture: Their benefits and hazards.
Interdiscip. Toxicol. 2009, 2, 1–12.
13. Wang, M.-C.; Gong, M.; Zang, H.-B.; Hua, X.-M.; Yao, J.; Pang, Y.-J.; Yang, Y.-H. Effect of Methamidophos
and Urea Application on Microbial Communities in Soils as Determined by Microbial Biomass and
Community Level Physiological Profiles. J. Environ. Sci. Health B 2006, 41, 399–413.
14. Miller, G.T. Sustaining the Earth; Brooks/Cole: Monterey County, USA, 2004; ISBN 9780534400880.
15. Lo, C.-C. Effect of pesticides on soil microbial community. J. Environ. Sci. Health Part B 2010, 45, 348–359.
16. Santos, A.; Flores, M. Effects of glyphosate on nitrogen fixation of free-living heterotrophic bacteria. Lett.
Appl. Microbiol. 1995, 20, 349–352.
17. Fabra, A.; Duffard, R.; Duffard, A.E. de Toxicity of 2,4-Dichlorophenoxyacetic Acid to Rhizobium sp in
Pure Culture. Bull. Environ. Contam. Toxicol. 1997, 59, 645–652.
18. Hussain, S.; Siddique, T.; Saleem, M.; Arshad, M.; Khalid, A. Chapter 5 Impact of Pesticides on Soil
Microbial Diversity, Enzymes, and Biochemical Reactions. Adv. Agron. 2009, 102, 159–200.
19. Monkiedje, A.; Spiteller, M. Degradation of Metalaxyl and Mefenoxam and Effects on the Microbiological
Properties of Tropical and Temperate Soils. Int. J. Environ. Res. Public. Health 2005, 2, 272–285.
Land 2020, 9, 34 17 of 22
20. Bano, S.A.; Iqbal, S.M. Biological Nitrogen Fixation to Improve Plant Growth and Productivity. Int. J. Agric.
Innov. Res. 2016, 4, 2319–1473.
21. Reitz, M.U.; Gifford, M.L.; Schäfer, P. Hormone activities and the cell cycle machinery in immunity-
triggered growth inhibition. J. Exp. Bot. 2015, 66, 2187–2197.
22. Milosevic, N.; Govedarica, M. Effect of herbicides on microbiological properties of soil. Matica Srp. Proc.
Nat. Sci. 2002, 102, 5–21.
23. Kremer, R.J.; Means, N.E. Glyphosate and glyphosate-resistant crop interactions with rhizosphere
microorganisms. Eur. J. Agron. 2009, 31, 153–161.
24. Yadav, G.; Datta, R.; Imran Pathan, S.; Lal, R.; Meena, R.; Babu, S.; Das, A.; Bhowmik, S.; Datta, M.; Saha,
P. Effects of Conservation Tillage and Nutrient Management Practices on Soil Fertility and Productivity of
Rice (Oryza sativa L.)–Rice System in North Eastern Region of India. Sustainability 2017, 9, 1816.
25. Santos, J.B.; Jakelaitis, A.; Silva, A.A.; Costa, M.D.; Manabe, A.; Silva, M.C.S. Action of two herbicides on
the microbial activity of soil cultivated with common bean (Phaseolus vulgaris) in conventional-till and no-
till systems. Weed Res. 2006, 46, 284–289.
26. Chen, F.; Dixon, R.A. Lignin modification improves fermentable sugar yields for biofuel production. Nat.
Biotechnol. 2007, 25, 759–761.
27. Datta, R.; Kelkar, A.; Baraniya, D.; Molaei, A.; Moulick, A.; Meena, R.S.; Formanek, P. Enzymatic
degradation of lignin in soil: A review. Sustainability 2017, 9, 1163.
28. Mishra, P.K.; Wimmer, R. Aerosol assisted self-assembly as a route to synthesize solid and hollow spherical
lignin colloids and its utilization in layer by layer deposition. Ultrason. Sonochem. 2017, 35, 45–50.
29. Mishra, P.K.; Ekielski, A. The Self-Assembly of Lignin and Its Application in Nanoparticle Synthesis: A
Short Review. Nanomaterials 2019, 9, 243.
30. Smith, A.R.W.; Beadle, C.A. Induction of enzymes of 2,4-dichlorophenoxyacetate degradation in
Burkholderia cepacia 2a and toxicity of metabolic intermediates. Biodegradation 2008, 19, 669–681.
31. Tsui, M.T.K.; Chu, L.M. Aquatic toxicity of glyphosate-based formulations: Comparison between different
organisms and the effects of environmental factors. Chemosphere 2003, 52, 1189–1197.
32. Brtnicky, M.; Dokulilova, T.; Holatko, J.; Pecina, V.; Kintl, A.; Latal, O.; Vyhnanek, T.; Prichystalova, J.;
Datta, R. Long-Term Effects of Biochar-Based Organic Amendments on Soil Microbial Parameters.
Agronomy 2019, 9, 747.
33. Khan, M.S.; Zaidi, A.; Rizvi, P.Q. Biotoxic Effects of Herbicides on Growth, Nodulation, Nitrogenase
Activity, and Seed Production in Chickpeas. Commun. Soil Sci. Plant Anal. 2006, 37, 1783–1793.
34. Seghers, D.; Verthé, K.; Reheul, D.; Bulcke, R.; Siciliano, S.D.; Verstraete, W.; Top, E.M. Effect of long-
term herbicide applications on the bacterial community structure and function in an agricultural soil. FEMS
Microbiol. Ecol. 2003, 46, 139–146.
35. Sannino, F.; Gianfreda, L. Pesticide influence on soil enzymatic activities. Chemosphere 2001, 45, 417–425.
36. Chalam, A.V.; Sasikala, C.; Ramana, C.V.; Uma, N.R.; Rao, P.R. Effect of Pesticides on the Diazotrophic
Growth and Nitrogenase Activity of Purple Nonsulfur Bacteria. Bull. Environ. Contam. Toxicol. 1997, 58,
37. Fox, J.E.; Starcevic, M.; Kow, K.Y.; Burow, M.E.; McLachlan, J.A. Nitrogen fixation: Endocrine disrupters
and flavonoid signalling. Nature 2001, 413, 128–129.
38. Syamsul Arif, M.A.; Houwen, F.; Verstraete, W. Agricultural factors affecting methane oxidation in arable
soil. Biol. Fertil. Soils 1996, 21, 95–102.
39. Subhani, A.; El-ghamry, A.M.; Changyong, H.; Jianming, X. Effects of Pesticides (Herbicides) on Soil
Microbial Biomass - A Review. Pak. J. Biol. Sci. 2000, 3, 705–709.
40. Singh, G.; Wright, D. In vitro studies on the effects of herbicides on the growth of rhizobia. Lett. Appl.
Microbiol. 2002, 35, 12–16.
41. Nowak, J.; Kaklewski, K.; Klódka, D. Influence of various concentrations of selenic acid (IV) on the activity
of soil enzymes. Sci. Total Environ. 2002, 291, 105–110.
42. Makarian, H.; Poozesh, V.; Asghari, H.R.; Nazari, M. Interaction Effects of Arbuscular Mycorrhiza Fungi
and Soil Applied Herbicides on Plant Growth. Commun. Soil Sci. Plant Anal. 2016, 47, 619–629.
43. Meena, R.S.; Meena, V.S.; Meena, S.K.; Verma, J.P. The needs of healthy soils for a healthy world. J. Clean.
Prod. 2015, 102, 560–561.
Land 2020, 9, 34 18 of 22
44. Powell, J.R.; Gulden, R.H.; Hart, M.M.; Campbell, R.G.; Levy-Booth, D.J.; Dunfield, K.E.; Pauls, K.P.;
Swanton, C.J.; Trevors, J.T.; Klironomos, J.N. Mycorrhizal and Rhizobial Colonization of Genetically
Modified and Conventional Soybeans. Appl. Environ. Microbiol. 2007, 73, 4365–4367.
45. Zawoznik, M.S.; Tomaro, M.L. Effect of chlorimuron-ethyl onBradyrhizobium japonicum and its symbiosis
with soybean. Pest Manag. Sci. 2005, 61, 1003–1008.
46. dos Santos, J.B.; Ferreira, E.A.; Kasuya, M.C.M.; da Silva, A.A.; de Oliveira Procópio, S. Tolerance of
Bradyrhizobium strains to glyphosate formulations. Crop Prot. 2005, 24, 543–547.
47. Strandberg, M.; Scott-Fordsmand, J.J. Effects of pendimethalin at lower trophic levels—a review. Ecotoxicol.
Environ. Saf. 2004, 57, 190–201.
48. Govedarica, M.; Miloševiã, N.; Konstantinoviã, B. Uticaj dimetenamida i metalahlora na mikrobiološka
svojstva zemljišta pod šeãernom repom. V Jugosl. Savetov. O Zašt. Bilja Zlatibor 2001, 12, 3–8.
49. Smith, S.E.; Read, D. Growth and carbon economy of arbuscular mycorrhizal symbionts. Mycorrhizal
Symbiosis 2008, 117–144. DOI: 10.1016/B978-012370526-6.50006-4
50. Pasaribu, A.; Mohamad, R.B.; Hashim, A.; Rahman, Z.A.; Omar, D.; Morshed, M.M.; Selangor, D.E. Effect
of herbicide on sporulation and infectivity of vesicular arbuscular mycorrhizal (Glomus mosseae)
symbiosis with peanut plant. J. Anim. Plant Sci. 2013, 23, 1671–1678.
51. Das, A.C.; Debnath, A.; Mukherjee, D. Effect of the herbicides oxadiazon and oxyfluorfen on phosphates
solubilizing microorganisms and their persistence in rice fields. Chemosphere 2003, 53, 217–221.
52. Zaller, J.G.; Heigl, F.; Ruess, L.; Grabmaier, A. Glyphosate herbicide affects belowground interactions
between earthworms and symbiotic mycorrhizal fungi in a model ecosystem. Sci. Rep. 2014, 4, 5634.
53. Savin, M.C.; Purcell, L.C.; Daigh, A.; Manfredini, A. Response of Mycorrhizal Infection to Glyphosate
Applications and P Fertilization in Glyphosate-Tolerant Soybean, Maize, and Cotton. J. Plant Nutr. 2009,
32, 1702–1717.
54. Sharma, M.P.; Buyer, J.S. Comparison of biochemical and microscopic methods for quantification of
arbuscular mycorrhizal fungi in soil and roots. Appl. Soil Ecol. 2015, 95, 86–89.
55. Druille, M.; Omacini, M.; Golluscio, R.A.; Cabello, M.N. Arbuscular mycorrhizal fungi are directly and
indirectly affected by glyphosate application. Appl. Soil Ecol. 2013, 72, 143–149.
56. Ipsilantis, I.; Samourelis, C.; Karpouzas, D.G. The impact of biological pesticides on arbuscular mycorrhizal
fungi. Soil Biol. Biochem. 2012, 45, 147–155.
57. Gupta, A.; Aggarwal, A.; Chhavi, M.; Kumar, A.; Tanwar, A. Effect of herbicides Fenoxaprop-P-ethyl and
2, 4-D Ethyl-ester on soil mycoflora including VAM fungi in wheat crop. Indian J. Weed Sci. India 2011, 43,
58. Kiers, E.T.; Duhamel, M.; Beesetty, Y.; Mensah, J.A.; Franken, O.; Verbruggen, E.; Fellbaum, C.R.;
Kowalchuk, G.A.; Hart, M.M.; Bago, A. Reciprocal rewards stabilize cooperation in the mycorrhizal
symbiosis. Science 2011, 333, 880–882.
59. Timmusk, S.; Behers, L.; Muthoni, J.; Muraya, A.; Aronsson, A.-C. Perspectives and challenges of microbial
application for crop improvement. Front. Plant Sci. 2017, 8, 49.
60. Kinney, C.A.; Mandernack, K.W.; Mosier, A.R. Laboratory investigations into the effects of the pesticides
mancozeb, chlorothalonil, and prosulfuron on nitrous oxide and nitric oxide production in fertilized soil.
Soil Biol. Biochem. 2005, 37, 837–850.
61. Mahía, J.; Cabaneiro, A.; Carballas, T.; Díaz-Raviña, M. Microbial biomass and C mineralization in
agricultural soils as affected by atrazine addition. Biol. Fertil. Soils 2008, 45, 99–105.
62. Antonious, G.F. Impact of Soil Management and Two Botanical Insecticides on Urease and Invertase
Activity. J. Environ. Sci. Health Part B 2003, 38, 479–488.
63. Virág, D.; Naár, Z.; Kiss, A. Microbial Toxicity of Pesticide Derivatives Produced with UV-
photodegradation. Bull. Environ. Contam. Toxicol. 2007, 79, 356–359.
64. Sáez, F.; Pozo, C.; Gómez, M.A.; Martínez-Toledo, M.V.; Rodelas, B.; Gónzalez-López, J. Growth and
denitrifying activity of Xanthobacter autotrophicus CECT 7064 in the presence of selected pesticides. Appl.
Microbiol. Biotechnol. 2005, 71, 563–567.
65. Demanou, J.; Sharma, S.; Weber, A.; Wilke, B.-M.; Njine, T.; Monkiedje, A.; Munch, J.C.; Schloter, M. Shifts
in microbial community functions and nitrifying communities as a result of combined application of copper
and mefenoxam. FEMS Microbiol. Lett. 2006, 260, 55–62.
66. Monkiedje, A. Soil quality changes resulting from the application of the fungicides mefenoxam and
metalaxyl to a sandy loam soil. Soil Biol. Biochem. 2002, 34, 1939–1948.
Land 2020, 9, 34 19 of 22
67. Madhuri, R.J.; Rangaswamy, V. Influence of selected insecticides on phosphatase activity in groundnut
(Arachis hypogeae L.) soils. J. Environ. Biol. 2002, 23, 393–397.
68. Van Zwieten, L.; Ayres, M.R.; Morris, S.G. Influence of arsenic co-contamination on DDT breakdown and
microbial activity. Environ. Pollut. 2003, 124, 331–339.
69. Kyei-Boahen, S.; Slinkard, A.E.; Walley, F.L. Rhizobial survival and nodulation of chickpea as influenced
by fungicide seed treatment. Can. J. Microbiol. 2001, 47, 585–589.
70. Kostov, O.; Van Cleemput, O. Microbial Activity of Cu Contaminated Soils and Effect of Lime and Compost
on Soil Resiliency. Compost Sci. Util. 2001, 9, 336–351.
71. Fravel, D.R.; Deahl, K.L.; Stommel, J.R. Compatibility of the biocontrol fungus Fusarium oxysporum strain
CS-20 with selected fungicides. Biol. Control 2005, 34, 165–169.
72. Cycoń, M.; Piotrowska-Seget, Z.; Kaczyńska, A.; Kozdrój, J. Microbiological characteristics of a sandy loam
soil exposed to tebuconazole and λ-cyhalothrin under laboratory conditions. Ecotoxicology 2006, 15, 639–
73. Datta, R.; Anand, S.; Moulick, A.; Baraniya, D.; Pathan, S.I.; Rejsek, K.; Vranova, V.; Sharma, M.; Sharma,
D.; Kelkar, A.; et al. How enzymes are adsorbed on soil solid phase and factors limiting its activity: A
Review. Int. Agrophysics 2017, 31, 287–302.
74. Smith, M.D.; Hartnett, D.C.; Rice, C.W. Effects of long-term fungicide applications on microbial properties
in tallgrass prairie soil. Soil Biol. Biochem. 2000, 32, 935–946.
75. Murillo-Williams, A.; Pedersen, P. Arbuscular Mycorrhizal Colonization Response to Three Seed-Applied
Fungicides. Agron. J. 2008, 100, 795.
76. Chen, S.-K.; Edwards, C.A.; Subler, S. Effects of the fungicides benomyl, captan and chlorothalonil on soil
microbial activity and nitrogen dynamics in laboratory incubations. Soil Biol. Biochem. 2001, 33, 1971–1980.
77. Shukla, A.K. Impact of fungicides on soil microbial population and enzyme activities. Acta Bot. Indica 2000,
28, 85–88.
78. Di Ciocco, C.A.; Rodríguez, C.E. Effect of the fungicide captan on Azospirillum brasilense Cd in pure
culture and associated with Setaria italica. Rev. Argent. Microbiol. 1997, 29, 152.
79. Milenkovski, S.; Bååth, E.; Lindgren, P.E.; Berglund, O. Toxicity of fungicides to natural bacterial
communities in wetland water and sediment measured using leucine incorporation and potential
denitrification. Ecotoxicology 2010, 19, 285–294.
80. Niewiadomska, A. Effect of Carbendazim, Imazetapir and Thiram on Nitrogenase Activity, the Number of
Microorganisms in Soil and Yield of Red Clover (Trifolium pratense L.). Pol. J. Environ. Stud. 2004, 13, 4.
81. Cycoń, M.; Piotrowska-Seget, Z.; Kozdrój, J. Responses of indigenous microorganisms to a fungicidal
mixture of mancozeb and dimethomorph added to sandy soils. Int. Biodeterior. Biodegrad. 2010, 64, 316–323.
82. Černohlávková, J.; Jarkovský, J.; Hofman, J. Effects of fungicides mancozeb and dinocap on carbon and
nitrogen mineralization in soils. Ecotoxicol. Environ. Saf. 2009, 72, 80–85.
83. Liebich, J.; Schäffer, A.; Burauel, P. Structural and functional approach to studying pesticide side-effects on
specific soil functions. Environ. Toxicol. Chem. 2003, 22, 784–790.
84. Verdisson, S.; Couderchet, M.; Vernet, G. Effects of procymidone, fludioxonil and pyrimethanil on two
non-target aquatic plants. Chemosphere 2001, 44, 467–474.
85. Durska, G. Fungicide effect on nitrogenase activity in methylotrophic bacteria. Pol. J. Microbiol. 2004, 53,
86. Madhuri, R.J.; Rangaswamy, V. Influence of selected fungicides on microbial population in groundnut
(Arachis hypogeae L.) soils. Pollut. Res. 2003, 22, 205–212.
87. Sukul, P. Enzymatic activities and microbial biomass in soil as influenced by metalaxyl residues. Soil Biol.
Biochem. 2006, 38, 320–326.
88. Yang, Q.; Zhang, J.; Zhu, K.; Zhang, H. Influence of oxytetracycline on the structure and activity of
microbial community in wheat rhizosphere soil. J. Environ. Sci. 2009, 21, 954–959.
89. Pal, R.; Chakrabarti, K.; Chakraborty, A.; Chowdhury, A. Pencycuron application to soils: Degradation and
effect on microbiological parameters. Chemosphere 2005, 60, 1513–1522.
90. Pereyra, M.A.; Ballesteros, F.M.; Creus, C.M.; Sueldo, R.J.; Barassi, C.A. Seedlings growth promotion by
Azospirillum brasilense under normal and drought conditions remains unaltered in Tebuconazole-treated
wheat seeds. Eur. J. Soil Biol. 2009, 45, 20–27.
91. Yen, J.-H.; Chang, J.-S.; Huang, P.-J.; Wang, Y.-S. Effects of fungicides triadimefon and propiconazole on
soil bacterial communities. J. Environ. Sci. Health Part B 2009, 44, 681–689.
Land 2020, 9, 34 20 of 22
92. Wainwright, M.; Pugh, G.J.F. Effect of fungicides on the numbers of micro-organisms and frequency of
cellulolytic fungi in soils. Plant Soil 1975, 43, 561–572.
93. Carr, J.F.; Gregory, S.T.; Dahlberg, A.E. Severity of the Streptomycin Resistance and Streptomycin
Dependence Phenotypes of Ribosomal Protein S12 of Thermus thermophilus Depends on the Identity of
Highly Conserved Amino Acid Residues. J. Bacteriol. 2005, 187, 3548–3550.
94. Martı́nez-Toledo, M. V.; Salmerón, V.; Rodelas, B.; Pozo, C.; González-López, J. Effects of the fungicide
Captan on some functional groups of soil microflora. Appl. Soil Ecol. 1998, 7, 245–255.
95. Marfo, T.D.; Datta, R.; Lojkova, L.; Janous, D.; Pavelka, M.; Formanek, P. Limitation of Activity of Acid
Phosphomonoesterase in Soils; Springer: Wien, Austria, 2015; Volume 47, p. 1691.
96. Datta, R.; Vranová, V.; Pavelka, M.; Rejšek, K.; Formánek, P. Effect of soil sieving on respiration induced
by low-molecular-weight substrates. Int. Agrophysics 2014, 28, 119–124.
97. Molaei, A.; Lakzian, A.; Datta, R.; Haghnia, G.; Astaraei, A.; Rasouli-Sadaghiani, M.; Ceccherini, M.T.
Impact of chlortetracycline and sulfapyridine antibiotics on soil enzyme activities. Int. Agrophys. 2017, 31,
98. Molaei, A.; Lakzian, A.; Haghnia, G.; Astaraei, A.; Rasouli-Sadaghiani, M.; Ceccherini, M.T.; Datta, R.
Assessment of some cultural experimental methods to study the effects of antibiotics on microbial activities
in a soil: An incubation study. PLoS ONE 2017, 12, e0180663.
99. Pandey, S.; Singh, D.K. Total bacterial and fungal population after chlorpyrifos and quinalphos treatments
in groundnut (Arachis hypogaea L.) soil. Chemosphere 2004, 55, 197–205.
100. Survery, S.; Ahmad, S.; Subhan, S.A.; Ajaz, M.; Rasool, S.A. Hydrocarbon Degrading Bacteria from
Pakistani Soil: Isolation, Identification, Screening and Genetical Studies. Pak. J. Biol. Sci. 2004, 7, 1518–1522.
101. Amirkhanov, D. V.; Nikolenko, A.G.; Bagautdinov, F.Y.; Kirillova, S.S. Effect of production dosage of
gamma-HCCH, foxim, cypermethrin and chlorfluazuron on soil microorganisms [grey forest
soils].[Russian]. Agrokhimiya 1994. 2, 83–88.
102. Ahmed, S.; Ahmad, M. Note: Toxicity of some insecticides onBracon hebetor under laboratory conditions.
Phytoparasitica 2006, 34, 401–404.
103. Gundi, V.A.K.B.; Narasimha, G.; Reddy, B.R. Interaction Effects of Insecticides on Microbial Populations
and Dehydrogenase Activity in a Black Clay Soil. J. Environ. Sci. Health Part B 2005, 40, 69–283.
104. Madhaiyan, M.; Poonguzhali, S.; Hari, K.; Saravanan, V.S.; Sa, T. Influence of pesticides on the growth rate
and plant-growth promoting traits of Gluconacetobacter diazotrophicus. Pestic. Biochem. Physiol. 2006, 84,
105. Das, A.C.; Mukherjee, D. Influence of Insecticides on Microbial Transformation of Nitrogen and
Phosphorus in Typic Orchragualf Soil. J. Agric. Food Chem. 2000, 48, 3728–3732.
106. Zhu, G.; Wu, H.; Guo, J.; Kimaro, F.M.E. Microbial Degradation of Fipronil in Clay Loam Soil. Water. Air.
Soil Pollut. 2004, 153, 35–44.
107. Shang, Y.; Hasan, M.; Ahammed, G.J.; Li, M.; Yin, H.; Zhou, J. Applications of nanotechnology in plant
growth and crop protection: A review. Molecules 2019, 24, 2558.
108. Patnaik, G.K.; Kanungo, P.K.; Adhya, T.K.; Rajaramamohan Rao, V. Effect of repeated applications of
gamma-hexachlorocyclohexane (γ-HCH) on nitrogenase activity and nitrogen-fixing bacteria associated
with rhizosphere of tropical rice. Microbiol. Res. 1996, 151, 375–378.
109. Kalam, A.; Mukherjee, A.K. Influence of hexaconazole, carbofuran and ethion on soil microflora and
dehydrogenase activities in soil and intact cell. Indian J. Exp. Biol. (IJEB) 2001, 39, 90–94.
110. Singh, J.; Singh, D.K. Dehydrogenase and phosphomonoesterase activities in groundnut (Arachis hypogaea
L.) field after diazinon, imidacloprid and lindane treatments. Chemosphere 2005, 60, 32–42.
111. Tu, C.M. Effect of five insecticides on microbial and enzymatic activities in sandy soil. J. Environ. Sci. Health
Part B 1995, 30, 289–306.
112. El-Ghamry, A.M.; Xu, J.M.; Huang, C.Y.; Gan, J. Microbial response to bensulfuron-methyl treatment in
soil. J. Agric. Food Chem. 2002, 50, 136–139.
113. Ingram, C.W.; Coyne, M.S.; Williams, D.W. Effects of Commercial Diazinon and Imidacloprid on Microbial
Urease Activity in Soil and Sod. J. Environ. Qual. 2005, 34, 1573.
114. Colores, G.M.; Schmidt, S.K. Recovery of Microbially Mediated Processes in Soil Augmented with A
Pentachlorophenol-Mineralizing Bacterium. Environ. Toxicol. Chem. 2005, 24, 1912.
Land 2020, 9, 34 21 of 22
115. Mayanglambam, T.; Vig, K.; Singh, D.K. Quinalphos Persistence and Leaching Under Field Conditions and
Effects of Residues on Dehydrogenase and Alkaline Phosphomonoesterases Activities in Soil. Bull. Environ.
Contam. Toxicol. 2005, 75, 1067–1076.
116. Qian, H.; Hu, B.; Wang, Z.; Xu, X.; Hong, T. Effects of validamycin on some enzymatic activities in soil.
Environ. Monit. Assess. 2007, 125, 1–8.
117. Enserink, M.; Hines, P.J.; Vignieri, S.N.; Wigginton, N.S.; Yeston, J.S. The pesticide paradox. Science 2013,
341, 728–729.
118. Owen, M.D.K.; Beckie, H.J.; Leeson, J.Y.; Norsworthy, J.K.; Steckel, L.E. Integrated pest management and
weed management in the United States and Canada. Pest Manag. Sci. 2015, 71, 357–376.
119. Lacey, L.A.; Georgis, R. Entomopathogenic nematodes for control of insect pests above and below ground
with comments on commercial production. J. Nematol. 2012, 44, 218.
120. Gupta, S.; Dikshit, A.K. Biopesticides: An ecofriendly approach for pest control. J. Biopestic. 2010, 3, 186.
121. Meena, A.K.; Meena, A.K. Characterization and antagonistic effect of isolated Trichoderma sp. against
pathogens under Clusterbean (Cyamopsis tetragonoloba L.). Indian J. Agric. Res. 2016, 50, 249–253.
122. Alam, G.; Alam, G. A Study of Biopesticides and Biofertilisers in Haryana, India; International Institute for
Environment and Development: London, UK, 2000.
123. Sharma, M.P.; Sharma, A.N.; Hussaini, S.S. Entomopathogenic nematodes, a potential microbial
biopesticide: Mass production and commercialisation status – a mini review. Arch. Phytopathol. Plant Prot.
2011, 44, 855–870.
124. Neal, A.L.; Ahmad, S.; Gordon-Weeks, R.; Ton, J. Benzoxazinoids in Root Exudates of Maize Attract
Pseudomonas putida to the Rhizosphere. PLoS ONE 2012, 7, e35498.
125. Akiyama, K.; Hayashi, H. Strigolactones: Chemical signals for fungal symbionts and parasitic weeds in
plant roots. Ann. Bot. 2006, 97, 925–931.
126. Broughton, W.J.; Zhang, F.; Perret, X.; Staehelin, C. Signals exchanged between legumes and Rhizobium:
Agricultural uses and perspectives. Plant Soil 2003, 252, 129–137.
127. Pathan, S.I.; Větrovský, T.; Giagnoni, L.; Datta, R.; Baldrian, P.; Nannipieri, P.; Renella, G. Microbial
expression profiles in the rhizosphere of two maize lines differing in N use efficiency. Plant Soil 2018, 433,
128. Gupta Sood, S. Chemotactic response of plant-growth-promoting bacteria towards roots of vesicular-
arbuscular mycorrhizal tomato plants. FEMS Microbiol. Ecol. 2003, 45, 219–227.
129. Gopal, M.; Gupta, A.; Arunachalam, V.; Magu, S.P. Impact of azadirachtin, an insecticidal allelochemical
from neem on soil microflora, enzyme and respiratory activities. Bioresour. Technol. 2007, 98, 3154–3158.
130. Govindachari, T.R.; Suresh, G.; Gopalakrishnan, G.; Masilamani, S.; Banumathi, B. Antifungal activity of
some tetranortriterpenoids. Fitoterapia 2000, 71, 317–320.
131. Coventry, E.; Allan, E.J. Microbiological and Chemical Analysis of Neem (Azadirachta indica) Extracts:
New Data on Antimicrobial Activity. Phytoparasitica 2001, 29, 441–450.
132. Elnasikh, M.H.; Osman, A.G.; Sherif, A.M. Impact of neem seed cake on soil microflora and some soil
properties. J. Sc. Tech. 2011, 12, 144–150.
133. Xu, X.; Chen, C.; Zhang, Z.; Sun, Z.; Chen, Y.; Jiang, J.; Shen, Z. The influence of environmental factors on
communities of arbuscular mycorrhizal fungi associated with Chenopodium ambrosioides revealed by
MiSeq sequencing investigation. Sci. Rep. 2017, 7, 45134.
134. Lu, F.C.; Lee, C.Y.; Wang, C.L. The influence of arbuscular mycorrhizal fungi inoculation on yam
(Dioscorea spp.) tuber weights and secondary metabolite content. PeerJ 2015, 3, e1266.
135. Kiran, U.; Patra, D.D. Medicinal and aromatic plant materials as nitrification inhibitors for augmenting
yield and nitrogen uptake of Japanese mint (Mentha arvensis L. Var. Piperascens). Bioresour. Technol. 2003,
86, 267–276.
136. Mohanty, S.; Patra, A.K.; Chhonkar, P.K. Neem (Azadirachta indica) seed kernel powder retards urease
and nitrification activities in different soils at contrasting moisture and temperature regimes. Bioresour.
Technol. 2008, 99, 894–899.
137. Medina, M.J.H.; Gagnon, H.; Piché, Y.; Ocampo, J.A.; Garrido, J.M.G.; Vierheilig, H. Root colonization by
arbuscular mycorrhizal fungi is affected by the salicylic acid content of the plant. Plant Sci. 2003, 164, 993–
138. Tilak, K.; Ranganayaki, N.; Pal, K.; De, R.; Saxena, A.K.; Nautiyal, C.S.; Mittal, S.; Tripathi, A.K.; Johri, B.N.
Diversity of plant growth and soil health supporting bacteria. Curr. Sci. 2005, 136–150.
Land 2020, 9, 34 22 of 22
139. Sethi, S.; Gupta, S. Impact of Pesticides and Biopesticides on Soil Microbial Biomass Carbon. Univers. J.
Environ. Res. Technol. 2013, 3, 2.
140. Tripathi, A.K.; Mishra, S. Plant Monoterpenoids (Prospective Pesticides). In Ecofriendly Pest Management for
Food Security; Academic Press: Cambridge, MA, USA, 2016; pp. 507–524.
141. Tan, S.; Chen, X.; Li, D. Progress in the studies on Helicoverpa spp. resistance to transgenic Bt cotton and
its management strategy. Kun Chong Xue Bao Acta Entomol. Sin. 2002, 45, 138–144.
142. Sessitsch, A.; Kan, F.Y.; Pfeifer, U. Diversity and community structure of culturable Bacillus spp.
populations in the rhizospheres of transgenic potatoes expressing the lytic peptide cecropin B. Appl. Soil
Ecol. 2003, 22, 149–158.
143. Liu, B.; Zeng, Q.; Yan, F.; Xu, H.; Xu, C. Effects of transgenic plants on soil microorganisms. Plant Soil 2005,
271, 1–13.
144. Mishra, P.K.; Ekielski, A.; Mukherjee, S.; Sahu, S.; Chowdhury, S.; Mishra, M.; Talegaonkar, S.; Siddiqui, L.;
Mishra, H. Wood-Based Cellulose Nanofibrils: Haemocompatibility and Impact on the Development and
Behaviour of Drosophila melanogaster. Biomolecules 2019, 9, 363.
145. Heuer, H.; Kroppenstedt, R.M.; Lottmann, J.; Berg, G.; Smalla, K. Effects of T4 Lysozyme Release from
Transgenic Potato Roots on Bacterial Rhizosphere Communities Are Negligible Relative to Natural Factors.
Appl. Environ. Microbiol. 2002, 68, 1325–1335.
146. Schmalenberger, A.; Tebbe, C.C. Genetic profiling of noncultivated bacteria from the rhizospheres of sugar
beet (Beta vulgaris) reveal field and annual variability but no effect of a transgenic herbicide resistance.
Can. J. Microbiol. 2003, 49, 1–8.
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... Phyllosphere microorganisms live on the leaf surface (epiphytic) and survive on trace quantities of available water and nutrients within that habitat. These epiphytes are typically pink-pigmented methylotrophic that are well known for their capability of production of plant growth hormones and alleviation of abiotic stress (es) in plant (Meena et al. , 2020. However, the abundance, activities, and assortment of rhizosphere microbiome appear to be far more superior to the phyllosphere (Laksmanan et al. 2014). ...
... Inoculation of IAA and SA (Salicylic acid) producing Bacillus sp. and Enterobacter sp. in Triticum aestivum and Zea mays enhances drought tolerance and plant growth (Jochum et al. 2020). The phyllosphere microbial community is also known to produce regulatory biomolecules like SA and IAA which induce salinity tolerance, for instance, in wheat (Meena et al. 2020). In addition to the phytohormones, phyllosphere microbes also synthesize osmoprotectants, vitamin B12, and polysaccharides into their environments (Bustillos-Cristales et al. 2017). ...
... Carbofuran 3G is another chemical that has been used against soil-borne pathogens especially plant-parasitic nematodes (Jada et al. 2011). The numerous problems associated with the use of synthetic chemicals in managing SBPP (Yamamoto et al. 2008;Sande et al. 2011;Meena et al. 2020) have necessitated a change of approach in favour of safe, effective, sustainable and environmental-friendly options in the management of these diseases. ...
Agroforestry is a practice of combining food crops with tree crops to create a more dynamic, versatile, and long-term exploitation of resources available on land to fulfill the requirements of growing populations. To boost production, chemical fertilizers are being widely used, but this is depleting our land resources of nutrients and has negative consequences for soil, water, the ecosystem, and crop quality and yield. As a result, there is a pressing need to transit from inorganic to organic agriculture techniques and microbial biofertilizer treatments, as they are essential to assuring crop yield and environmental protection. These microbial biofertilizers can improve plant health by affecting making nutrient available to them, releasing plant growth regulators, and offering protection against various diseases, all while increasing crop output. Plant-beneficial bacteria are said to be enhanced by agroforestry systems as well. The current analysis focuses on proper land utilization in the form of agroforestry, for fulfilling 3F (food, fodder, and fuel) through microbial biofertilizer interventions while also addressing environmental and health concerns.
... To solve this problem several selective and nonselective, pre-and post-emergent inorganic chemical fertilizers are being used at recommended doses. The overreliance and overuse of these inorganic chemical fertilizers tend to pollute the soil and nontarget crops by influencing the ability of plant growth promoting microbes and nitrogen fixing cyanobacteria [7]. It may add substantial amount of residual product in the soil ecosystem [8] leading to severe ecological consequences. ...
... Pest management is key to ensuring the provision of affordable and safe food (Cooper and Dobson, 2007;Möhring et al., 2019;Savary et al., 2019). However, the use of pesticides implies negative effects on human health and the environment (Malaj et al., 2014;De Souza et al., 2020;Meena et al., 2020;Gill et al., 2012;Rani et al., 2021;Tang et al., 2021). Thus, the reduction in pesticide risks without harming food security and farmers' income is a key policy goal. ...
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CONTEXT The use of pesticides implies negative effects on human health and the environment. Thus, the reduction in pesticide risks without harming food security and farmers' income is a key policy goal. OBJECTIVE The aim is to investigate the implications of policies that explicitly foster the large-scale adoption of pesticide-free, non-organic production systems at the national scale using Swiss crop production as an illustrative example. METHODS We develop a bio-economic modelling approach that combines agent-based modelling, a Delphi study to assess yield implications and a detailed representation of labour and machinery implications of pesticide-free, non-organic production. Using an agent-based modelling framework allows the consideration of heterogeneous farm-specific adaptation responses to voluntary direct payments for crop-specific conversion to pesticide-free but non-organic production systems. The modelling framework is used to assess the effects of changing pesticide policies on farm and sector levels and its implications for (crop-specific) food production in terms of area, volume, value and income. Our approach is illustrated using Switzerland as an example, where voluntary direct payments for a crop-specific conversion to pesticide-free but non-organic production systems will be implemented. RESULTS AND CONCLUSIONS The results show that the extent of crop-specific yield losses has an especially significant effect on the adoption rate of pesticide-free cropping systems. The impacts of introducing voluntary direct payments for pesticide-free production at the national scale imply reduced food (volume) and calorie production but only minimal reductions in the production value, especially due to expected higher prices for pesticide-free products. The effects on farmers' income are small, as participation in pesticide-free production is compensated with direct payments and higher prices and often implies cost reduction in labour and machinery due to non-use of pesticides. To establish large-scale production systems between conventional and organic cropping systems and, thereby, reduce trade-offs resulting from both extremes, policy schemes need to be flexible, allowing the adoption of a pesticide-free paradigm for some parts of the crop rotation but not necessarily entire crop rotations. SIGNIFICANCE This is the first national-scale study on the implications of adopting a pesticide-free, non-organic crop production system by using Swiss crop production as an illustrative example.
... This suggests that an active indigenous population of rhizobia and AM fungi existed in the nature farming soil, which was severely impacted by fumigation. From this results, it can be hypothesize that the fumigant negatively affected nodulation and consequently biological nitrogen fixation in the soybean by disrupting the signaling activities of Rhizobium needed for root infection or by affecting the root hairs of the soybean where infection and node formation occur (Meena et al., 2020). Previous research has shown that soil fumigants, such as chloropicrin and formaldehyde, inhibit AMF root infection and spore development (Dangi et al., 2017), which is attributed to the toxic effects of fumigants on the fungal spore and hyphal development. ...
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Nature farming is a farming system that entails cultivating crops without using chemical fertilizers and pesticides. The present study investigated the bacterial and fungal communities in the rhizosphere of soybean grown in conventional and nature farming soils using wild-type and non-nodulating mutant soybean. The effect of soil fumigant was also analyzed to reveal its perturbation of microbial communities and subsequent effects on the growth of soybean. Overall, the wild-type soybean exhibited a better growth index compared to mutant soybean and especially in nature farming. Nodulation and arbuscular mycorrhiza (AM) fungi colonization were higher in plants under nature farming than in conventionally managed soil; however, fumigation drastically affected these symbioses with greater impacts on plants in nature farming soil. The rhizosphere microbiome diversity in nature farming was higher than that in conventional farming for both cultivars. However, the diversity was significantly decreased after fumigation treatment with a greater impact on nature farming. Principal coordinate analysis revealed that nature farming and conventional farming soil harbored distinct microbial communities and that soil fumigation significantly altered the communities in nature farming soils but not in conventional farming soils. Intriguingly, some beneficial microbial taxa related to plant growth and health, including Rhizobium , Streptomyces , and Burkholderia , were found as distinct microbes in the nature farming soil but were selectively bleached by fumigant treatment. Network analysis revealed a highly complex microbial network with high taxa connectivity observed under nature farming soil than in conventional soil; however, fumigation strongly broke it. Overall, the results highlighted that nature farming embraced higher microbial diversity and the abundance of beneficial soil microbes with a complex and interconnected network structure, and also demonstrated the underlying resilience of the microbial community to environmental perturbations, which is critical under nature farming where chemical fertilizers and pesticides are not applied.
Long-term and indiscriminate use of synthetic pesticides to mitigate plant pathogens have created serious issues of water health, soil contamination, non-target organisms, resistant species, and unpredictable environmental and human health hazards. These constraints have forced scientists to develop alternative plant disease management strategies to reduce synthetic chemical' dependency. During the last 20 years, biological agents and resistance elicitors have been the most important used alternatives. Silica-based materials/chitosan with a dual mode of action have been proposed as promising alternatives to prevent plant diseases through direct and indirect mechanisms. Moreover, the combined application of nano-silica and chitosan, due to their controllable morphology, high loading capacity, low toxicity, and efficient encapsulation, act as suitable carriers for biological agents, pesticides, and essential oils, making them proper candidates for mitigation of phytopathogens. Based on this potential, this literature study reviewed the silica and chitosan properties and their function in the plant. It also assessed their role in the fighting against soil and aerial phytopathogens, directly and indirectly, as novel hybrid formulations in future managing platforms.
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An increase in the pesticide load in agro-cenoses leads to a decrease in the number of the main ecological and trophic groups of microorganisms, which causes a disruption of connections in agro-ecosystems and soil biological activity. For example, more than 95% of applied pesticides have a greater impact on soil microorganisms than on their target objects, as they are sprayed proportionally all over the field, regardless of the affected areas. In this case, fire treatment has the main benefit of a more targeted treatment, which is more focused on its main object of impact. But, as you know, fire can also cause significant damage to both soil and microorganisms living there. Soil microbiota is very sensitive to environmental changes, but it is completely killed only at soil temperatures above +120°C, so treatment with a fire cultivator that can work at both +100°C and +70°C has a high chance of becoming the safest way to control weeds. Despite the known negative effect of fires and flames on soils, to fully assess the impact of this method on soil and its fertility, it is necessary to investigate the impact of this treatment primarily on changes in the microbiological characteristics of the surface soil layer. The treatment was carried out using two modes of the fire cultivator (+70°C and +100°C). Microbiological analyzes of the soil were carried out according to generally accepted methods. The content of total biomass of microorganisms in the soil was determined by the rehydration method. Thus, to study the impact of fire cultivation on the direction of processes in the soil and the main ecological and trophic groups of microorganisms, we determined the content of total biomass of microorganisms, coefficients of mineralization-immobilization and oligotrophicity, cellulolytic activity, the number of bacteria, micromycetes, etc. Our analysis of the total microbial biomass of the selected soil samples allows us to assert the safety of the applied fire method of weed control. In the study of soil fouling lumps (Ashby's medium), 100% presence of bacteria of the genus Azotobacter was noted in all variants with temperature treatment. The analysis of soil samples on Ashby's medium showed that oligotrophs do not significantly change under fire treatment at 70°C, but some negative impact on the vital activity of these microorganisms is still observed under 100°C treatment. The obtained ecological coefficients of the direction of microbiological processes indicate the decreasing intensity of decomposition of soil organic matter, in particular humus compounds and reducing soil oligotrophicity indicates an increase in the content of nutrients in the soil. For the most environmental benefits, we recommend to use a milder fire treatment of 70°C, wich allows not only to control the weeds, but also stimulates and directs microbiological processes in a positive direction. Our analysis of the impact of fire cultivation on the direction of processes in the soil and the main ecological and trophic groups of microorganisms showed the usefulness of recommending this method for weed treatment. Moreover, its softer treatment with fire at 70°C allows not only to control the weeds, but also can stimulate and coordinate microbiological processes in a positive direction, i.e., to accumulate nutrients. This allows to recommend this method not only for weed control under traditional agricultural conditions, but also for organic farming.
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The shifting in either RTDSR or ZTDSR resulted in yield penalty in rice compared to PTR. The PTR recorded highest pooled grain yield of . ha−. The rice grain yield reduced about .% under DSR as compared to PTR. The ZTB along with residue treatments exhibited significantly higher grain yield over ZTB, and the RTDSRZTBRRregistered highest pooled grain yield of barley. The system productivity (.t ha−) and sustainable yield index (.) were highest under UPTRZTBRR. Biological parameters including microbial biomass carbon, soil respiration, microbial enzymes (Alkaline phosphatase, nitrate reductase and peroxidase), fluorescein diacetate hydrolysis, ergosterol, glomalin related soil proteins, microbial population (bacteria, fungi and actinobacteria) were found to be significantly (p < .) eected by dierent nutrient management practices. Based on the PCA analysis, Fluorescein diacetate hydrolysis, microbial biomass carbon, soil respiration, nitrate reductase and fungi population were the important soil biological parameters indicating soil quality and productivity in present experiment. The results concluded that UPTRZTBRRwas a more suitable practice for maintaining system productivity and soil biological hea
Soil is the home to diverse groups of microorganisms. Some of these organisms are beneficial while others are pathogenic, causing ill health, poor growth and yield of crops. In the past, fallowing was the most common response to soil infestation with pathogens and declining crop productivity in Africa. However, this is gradually being replaced with the use of synthetic soil fumigants and nematicides. Environmental and health concerns have brought about agitation for safer methods of managing soil-borne diseases of plants (SBDP). Biological control, through the use of plant growth-promoting microorganisms (PGPM), is an alternative that has shown great promise in parts of the world where it has been adopted for the management of SBDP. This chapter takes a look at some of the common soil-borne plant pathogens in Africa and the diseases they cause. The current status of research on the management of these diseases, in vitro and in vivo, is given extensive review. The success recorded in the commercial production of PGPM in ready to use form is also reported. The benefits and limitations of PGPM formulations in managing SBDP are discussed. Conclusively, the need for increased commercial production of PGPM formulations in the continent, and for such formulations to be made readily available to the farmers, is pointed out. This will encourage more adoption and utilization of PGPM in the management of SBDP.
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Biochar application to the soil has been recommended as a carbon (C) management approach to sequester C and improve soil quality. Three-year experiments were conducted to investigate the interactive effects of three types of amendments on microbial biomass carbon, soil dehydrogenase activity and soil microbial community abundance in luvisols of arable land in the Czech Republic. Four different treatments were studied, which were, only NPK as a control, NPK + cattle manure, NPK + biochar and NPK + combination of manure with biochar. The results demonstrate that all amendments were effective in increasing the fungal and bacterial biomass, as is evident from the increased values of bacterial and fungal phospholipid fatty acid analysis. The ammonia-oxidizing bacteria population increases with the application of biochar, and it reaches its maximum value when biochar is applied in combination with manure. The overall results suggest that co-application of biochar with manure changes soil properties in favor of increased microbial biomass. It was confirmed that the application of biochar might increase or decrease soil activity, but its addition, along with manure, always promotes microbial abundance and their activity. The obtained results can be used in the planning and execution of the biochar-based soil amendments.
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Topographic and edaphic gradients usually arrange ecotonal boundaries. Although the interrelationships between vegetation and edaphic factors are relevant in most types of ecotones, they are not adequately documented. The clearly defined forest-agriculture land ecotone at the Proklest experimental site of the Training Forest Enterprise (T.F.E), Masaryk Forest Křtiny, Czech Republic presents an opportunity to investigate these interrelationships. Our aim was to determine ecotone effects reflected by changes in soil reaction and other soil physical properties across this clearly defined forest-agriculture land ecotone. We selected eleven sampling spots: four in the forest zone, four in the agriculture land, and three in the ecotone zone between the forest and agriculture land. Every month from April to November, soil samples were collected at a depth of 5 cm. All the soil samples collected were examined for minimal air capacity, actual and potential soil reaction, and maximum capillary water capacity. The forest soil was slightly more acidic when compared to the agriculture soil, with the ecotone zone recording the lowest pH value. The maximum capillary water capacity was higher in the forest region than in the agriculture land with a sharp decline in the ecotone zone where the lowest value was recorded. The minimum air capacity was much higher in the forest region than in the agriculture land. There was a marked decline in the ecotone region where the lowest value was observed. Our results highlight the importance of soil as a factor affecting the distribution of plant communities along ecotones.
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Wood-based cellulose nanofibrils (CNF) offer an excellent scaffold for drug-delivery formulation development. However, toxicity and haemocompatibility of the drug carrier is always an important issue. In this study, toxicity-related issues of CNF were addressed. Different doses of CNF were orally administered to Drosophila and different tests like the developmental cycle, trypan blue exclusion assay, larva crawling assay, thermal sensitivity assay, cold sensitivity assay, larval light preference test, climbing behaviour, nitroblue tetrazolium (NBT) reduction assay, adult phenotype, and adult weight were conducted to observe the impact on its development and behaviour. A haemocompatibility assay was done on the blood taken from healthy Wistar rats. In Drosophila, the abnormalities in larval development and behaviour were observed in the behavioural assays. However, the cytotoxic effect could not be confirmed by the gut staining and level of reactive oxygen species. The larvae developed into an adult without any abnormality in the phenotype. The CNF did cause loss of weight in the adult flies and did not cause much toxicity within the body since there was no phenotypic defect. Hemolysis data also suggested that CNF was safe at lower doses, as the data was well within acceptable limits. All these results suggest that cellulose nanofibres have no significant cytotoxic effects on Drosophila. However, the developmental and behavioural abnormalities suggest that CNF may act as a behavioural teratogen.
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In the era of climate change, global agricultural systems are facing numerous, unprecedented challenges. In order to achieve food security, advanced nano-engineering is a handy tool for boosting crop production and assuring sustainability. Nanotechnology helps to improve agricultural production by increasing the efficiency of inputs and minimizing relevant losses. Nanomaterials offer a wider specific surface area to fertilizers and pesticides. In addition, nanomaterials as unique carriers of agrochemicals facilitate the site-targeted controlled delivery of nutrients with increased crop protection. Due to their direct and intended applications in the precise management and control of inputs (fertilizers, pesticides, herbicides), nanotools, such as nanobiosensors, support the development of high-tech agricultural farms. The integration of biology and nanotechnology into nonosensors has greatly increased their potential to sense and identify the environmental conditions or impairments. In this review, we summarize recent attempts at innovative uses of nanotechnologies in agriculture that may help to meet the rising demand for food and environmental sustainability.
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Transitional areas between two or more different biomes—ecotones—are clearly visible due to the sudden changes in vegetation structures and patterns. However, much is still unknown about the crucial soil factors that control such vegetational changes across ecotones and how different soil properties vary across ecotones. In this study, we try to understand the spatial variation in soil properties across a clearly defined ecotone from a forest stand to meadow field at the Training Forest Enterprise (T.F.E), Masaryk Forest Křtiny, Czechia. Thirteen sampling sites were selected: six in the forest region, six in the meadow and one in the ecotone zone between forest and meadow. Soil samples were taken at 5 cm below the soil surface once every month from April to November. All the collected soil samples were examined for minimal air capacity, actual and potential soil reaction and maximum capillary water. The results showed a pattern of soil acidity decreasing from the forest stand towards the meadow field but that increased sharply at the ecotone zone. The water holding capacity showed a decreasing trend approaching the ecotone zone from the meadow region and markedly decreased from the meadow site closest to the ecotone zone. The minimum air capacity showed an increasing trend from the forest region but suddenly declined at the ecotone region.
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Lignin serves as a significant contributor to the natural stock of non-fossilized carbon, second only to cellulose in the biosphere. In this review article, we focus on the self-assembly properties of lignin and their contribution to its effective utilization and valorization. Traditionally, investigations on self-assembly properties of lignin have aimed at understanding the lignification process of the cell wall and using it for efficient delignification for commercial purposes. In recent years (mainly the last three years), an increased number of attempts and reports of technical-lignin nanostructure synthesis with controlled particle size and morphology have been published. This has renewed the interests in the self-assembly properties of technical lignins and their possible applications. Based on the sources and processing methods of lignin, there are significant differences between its structure and properties, which is the primary obstacle in the generalized understanding of the lignin structure and the lignification process occurring within cell walls. The reported studies are also specific to source and processing methods. This work has been divided into two parts. In the first part, the aggregation propensity of lignin based on type, source and extraction method, temperature, and pH of solution is discussed. This is followed by a critical overview of non-covalent interactions and their contribution to the self-associative properties of lignin. The role of self-assembly towards the understanding of xylogenesis and nanoparticle synthesis is also discussed. A particular emphasis is placed on the interaction and forces involved that are used to explain the self-association of lignin.
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Aims Study of the microbial expression profile in the rhizosphere of two contrasting maize lines, differing in the Nitrogen Use efficiency (NUE). Methods The Lo5 and T250 inbred maize characterized by high and low NUE, respectively, were grown in rhizoboxes allowing precise sampling of rhizosphere and bulk soils. We conducted metatranscriptomic of rhizosphere and bulk soil by m-RNA sequencing. Results High activity of bacteria was observed compared to archaea and fungi in both rhizosphere and bulk soils of both maize lines. Proteobacteria and Actinobacteria were involved in all processes, while significant shifts occurred in the expression of Bacteroidetes, Chloroflexi, Firmicutes, Acidobacteria, Cyanobacteria, archaea and fungi, indicating their possible role in specific processes occurring in rhizosphere of two maize lines. Maize plants with different NUE induced changes in microbial processes, especially in N cycling, with high NUE maize favouring ammonification and nitrification processes and low NUE maize inducing expression of genes encoding for denitrifying process, likely favoured by longer N residence time in the rhizosphere. Conclusions Overall our results showed that maize lines with different NUE shaped not only microbial communities but also conditioned the microbial functions and the N cycle in their rhizosphere. While the plant NUE is genetically determined and an inherent plant physiological trait, it also stimulates changes in the microbial community composition and gene expression in the rhizosphere, favouring microbial processes that mineralize and oxidize N in the high NUE maize. These results can improve our understanding on plant-microbe interaction in the rhizosphere of crop plants with potential applications for improving the management practices of the agro-ecosystems.
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Ecological weed management differs from traditional weed management in several ways. Ecological weed management strategy is to integrate the options and tools, rather than on specific control practices which are available to make the crops and cropping system unfavorable for weeds and to minimize the impact of any weed that survive. Maintaining appropriate crop rotation with legume and non-legume crops, and growing of cover crop helps to suppress weeds by smothering and allelopathic effects. Growing competitive cultivars, modifying in sowing and planting techniques, changing sowing and planting time, mulching with organic residues, green and brown manuring and the adoption of reduced or zero tillage makes an inappropriate environment for weed seed germinations and their growth. It also stores a higher amount of organic matter by reducing the mineralization rates and subsequently decreases energy consumption and carbon oxide emission. Herbicide use has been a valuable asset for modern agriculture; however, prudent use of chemicals for weed control is essential to fulfilling the goals of sustainable crop production, by reducing detrimental environmental impact, and delaying herbicide resistance development. Further development and testing of alternative weed management practices that can be utilized along with herbicide applications must be pursued in order to make the practice sustainable and successful.
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Pharmaceutical antibiotics are frequently used in the livestock and poultry industries to control infectious diseases. Due to the lack of proper guidance for use, the majority of administrated antibiotics and their metabolites are excreted to the soil environment through urine and feces. In the present study, we used chlortetracycline and sulfapyridine antibiotics to screen out their effects on dehydrogenase, alkaline phosphatase and urease activity. Factorial experiments were conducted with different concentrations of antibiotic (0, 10, 25 and 100 mg kg-1 of soil) mixed with soil samples, and the enzyme activity was measured at intervals of 1, 4 and 21 days. The results show that the chlortetracycline and sulfapyridine antibiotics negatively affect the dehydrogenase activity, but the effect of sulfapyridine decreases with time of incubation. Indeed, sulfapyridine antibiotic significantly affects the alkaline phosphatase activity for the entire three-time interval, while chlortetracycline seems to inhibit its activity within 1 and 4 days of incubation. The effects of chlortetracycline and sulfapyridine antibiotics on urease activity appear similar, as they both significantly affect the urease activity on day 1 of incubation. The present study concludes that chlortetracycline and sulfapyridine antibiotics have harmful effects on soil microbes, with the extent of effects varying with the duration of incubation and the type of antibiotics used.