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Abstract

Weeds are a hidden foe for crop plants, interfering with their functions and suppressing their growth and development. Yield losses of ∼34% are caused by weeds among the major crops, which are grown worldwide. These yield losses are higher than the losses caused by other pests in the crops. Sustainable weed management is needed in the wake of a huge decline in crop outputs due to weed pressure. A diversity in weed management tools ensures sustainable weed control and reduces chances of herbicide resistance development in weeds. Allelopathy as a tool, can be importantly used to combat the challenges of environmental pollution and herbicide resistance development. This review article provides a recent update regarding the practical application of allelopathy for weed control in agricultural systems. Several studies elaborate on the significance of allelopathy for weed management. Rye, sorghum, rice, sunflower, rape seed, and wheat have been documented as important allelopathic crops. These crops express their allelopathic potential by releasing allelochemicals which not only suppress weeds, but also promote underground microbial activities. Crop cultivars with allelopathic potentials can be grown to suppress weeds under field conditions. Further, several types of allelopathic plants can be intercropped with other crops to smother weeds. The use of allelopathic cover crops and mulches can reduce weed pressure in field crops. Rotating a routine crop with an allelopathic crop for one season is another method of allelopathic weed control. Importantly, plant breeding can be explored to improve the allelopathic potential of crop cultivars. In conclusion, allelopathy can be utilized for suppressing weeds in field crops. Allelopathy has a pertinent significance for ecological, sustainable, and integrated weed management systems.

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... Weeds are one of the largest global biological constraints of crop production [1]. Weeds compete with crops for space, soil nutrients, water, light, and other growth requirements, and cause huge yield losses of −34% among major crops [1][2][3]. ...
... Weeds are one of the largest global biological constraints of crop production [1]. Weeds compete with crops for space, soil nutrients, water, light, and other growth requirements, and cause huge yield losses of −34% among major crops [1][2][3]. ...
... The major challenges in hand weeding are decreasing availability and the increasing cost of labor [7]. In mechanical weed control, the soil structure is disturbed and the soil fertility is depleted due to additional soil turnover [1]. Similarly, challenges in the application of herbicides for weed control include the emergence of herbicide-resistant weeds and the side effects on environmental, human, and animal health [8]. ...
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This study aimed to assess the phytotoxic potential of fleagrass (Adenosma buchneroides) on weeds and crops. We assessed the effects of applying aqueous extracts of fleagrass on the seed germination and seedling growth of three weeds (Bidens pilosa, Paspalum thunbergia, and Bromus japonicus) and two crops (Oryza sativa and Zea mays). The influence of six doses of fleagrass aqueous extract on seed germination and seedling growth was assessed through a Petri dish experiment. The aqueous extract of fleagrass was qualitatively characterized using widely targeted metabolomics analysis and found to mainly comprise flavonoids, phenolic acids, alkaloids, polysaccharides, phenylpropanoids, terpenoids, phenolamides, and quinones. The mean IC50 for crop seed germination was 168,796, and the mean IC50 for weed seed germination was 11,454. The inhibition effect on the tested species, from highest to lowest, followed the order of B. japonicus > B. Pilosa > P. thunbergii > O. sativa > Z. mays. These results indicate the remarkable species-specific sensitivity of seed germination and seedling growth to fleagrass extract treatment, and that crops are more tolerant than weeds. Elucidation of the details of the fleagrass–weed/crop interaction can serve as a basis for intercropping fleagrass with crops in weed management strategies aimed at controlling weeds.
... Перекрестная устойчивость быстро развивается у сорняков, они стали устойчивыми к тем химическим веществам, которые впервые применены или относятся к разным химическим классам [105]. Jabran et al. (2015) высказали мнение, что устойчивость или перекрестная резистентность среди сорняков представляет серьезную угрозу для гербицидной промышленности и практики борьбы с сорняками [106]. Поскольку современные гербицидные продукты теряют свою эффективность из-за развития устойчивости, химический контроль над сорняками оказывается более сложным, а количество действующих веществ также сокращается из-за законодательных ограничений. ...
... Перекрестная устойчивость быстро развивается у сорняков, они стали устойчивыми к тем химическим веществам, которые впервые применены или относятся к разным химическим классам [105]. Jabran et al. (2015) высказали мнение, что устойчивость или перекрестная резистентность среди сорняков представляет серьезную угрозу для гербицидной промышленности и практики борьбы с сорняками [106]. Поскольку современные гербицидные продукты теряют свою эффективность из-за развития устойчивости, химический контроль над сорняками оказывается более сложным, а количество действующих веществ также сокращается из-за законодательных ограничений. ...
Article
Weeds are a major threat in crop production, and controlling them in modern agriculture is critical to preventing crop losses and ensuring food security. Intensive farming practices, climate change and natural disasters affect weed dynamics, requiring a change in management practices. Existing methods are no longer viable due to lack of manpower; chemical control methods are limited by health hazards and the development of herbicide resistance in weeds. This article discusses some potential alternative weed control strategies in modern vegetable production that are feasible and effective. Increasing the competitiveness of vegetable crops through proper planning of agrotechnologies system, preventive, cultural and mechanical methods, development of competitive varieties, allelopathy, biological control and reduction of weed seed production at harvest will be a major aspect in sustainable weed management. Improving tillage regimes has long been considered the main measure of weed control. Control of weed seed production and weed injuriousness have been shown as potential tools to reduce weed seed germination and retention in the soil. The development of allelopathy has led to the emergence of new methods of weed control. The use of the allelopathic potential of crops also deserves mention in modern weed control methods. Thermal weed control is seen as a useful method. The role of bioherbicides as an integral part of sustainable weed management is emphasized. All of these strategies are viable for modern agriculture; however, choosing a specific method and using the right combinations will be the key to success. No strategy is perfect, and therefore an integrated approach can provide the best results. The adoption of such practices can improve the efficiency of farming systems in sustainable agricul- ture. A comprehensive method for protecting vegetable crops from weeds and ways to reduce the potential contamination of fields with seeds and weed seedlings are described. The optimal norms and technological features, conditions for the effective use of modern herbicides on crops and plantings of vegetable crops are given.
... Therefore, current researchers are increasingly focusing on developing eco-friendly herbicides using natural products, and allelochemicals are being verified as an alternative to the use of chemical herbicides worldwide [5,6]. For example, Jabran et al. [7] reported that allelopathic plants can potentially reduce weed pressure, resulting in improved crop alternative to the use of chemical herbicides worldwide [5,6]. For example, Jabran et al. [7] reported that allelopathic plants can potentially reduce weed pressure, resulting in improved crop yields and reduced synthetic pesticide use. ...
... For example, Jabran et al. [7] reported that allelopathic plants can potentially reduce weed pressure, resulting in improved crop alternative to the use of chemical herbicides worldwide [5,6]. For example, Jabran et al. [7] reported that allelopathic plants can potentially reduce weed pressure, resulting in improved crop yields and reduced synthetic pesticide use. It has also been reported that P. densiflora and P. koraiensis are allelopathic plants, whose allelopathic effects are derived from non-volatile and volatile compounds including phenolics, flavonoids, and monoterpenes [8]. ...
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With allelopathic composts, potential merits for preventing initial weed infestations have been observed in crop transplantation. However, previous studies have rarely investigated whether high temperatures, generated during composting, decrease allelopathic ability. This study evaluated the thermal allelopathic effect of two coniferous plants (Pinus densiflora and P. koraiensis) on Brassica napus germination and seedling growth using their characterized allelochemical destinations. The 90 °C dry treatment of P. densiflora extract exhibited stronger inhibitory effect on germination than its 30 °C dry treatment. In a range from 0.25 to 1 mg mL−1, the germination rate was decreased to 38.1 and 64.3% of control with P. densiflora extract dried at 90 and 30 °C, respectively. However, P. koraiensis showed potent inhibition of the germination process with no statistical difference in inhibitory effects regardless of the dry temperature. Regarding B. napus seedling root growth, the allelopathic effects of aqueous extracts of both conifers were not reduced with the 90 °C treatment, but it was lost in seedling shoot growth. GC-MS/MS confirmed that high temperature treatment drastically decreased volatile contents to 53.2% in P. densiflora, resulting in reduced allelopathic abilities. However, a relatively lower decrease to 83.1% in volatiles of P. koraiensis accounts for less loss of the root-specific inhibitory effect on B. napus seedlings even after 90 °C treatment. Foliar tissues of both conifers with species-specific thermal resistance have potentially valuable functions regarding allelopathic use in horticultural compost processing ingredients, demonstrating their weed control ability during the early cultivation season where crops are transplanted in the facilitated area.
... Screening, selection and cultivating wheat varieties with significant allelopathic potential will be a good choice for eco-friendly weed management (Jabran et al., 2015). Organic farmers are particularly interested in cultivars that possess the potential to inhibit weed growth (Schalchli et al., 2012). ...
... For sustainable weed management and eco-friendly agriculture, wheat cultivars can be employed for weed management (Jabran et al., 2015). This information is important for organic farmers who have to control weeds without the use of herbicides. ...
Article
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Allelopathic activity of wheat (Triticum aestivum L.) has previously been associated with the production of phenolic acids and flavonoids (PAF), benzoxazinones (BXZs) and phenoxazinones (PXZs). The biosynthesis of BXZs is closely regulated during cereal growth, with accumulation highest in young tissues with variation associated with genotype and environmental conditions. This review is focused on BXZ metabolites and their impact on germination, seedling growth and physiological, biochemical, transcriptional and proteome traits of surrounding plants and weeds. The major pathways employed by plants for benzoxazinoid detoxification involve hydroxylation and glucosylation and polymerisation of intermediates in these pathways. Allelochemicals from various wheat genotypes have been shown to inhibit the growth of selected weed species, including Bromus japonicus, Chenopodium album, Portulaca oleracea, Avena fatua and Lolium rigidum. Wheat allelopathy is potentially exploited from the standpoint of crop mulches, incorporation of crop residues, tissue disruption, intercropping with allelopathic cultivars and application of aqueous wheat extracts. BXZs have been shown to suppress the growth and development of certain agricultural pests, including insects, fungal pathogens, and weeds. Many native plants, fungi and insect herbivores inherently possess varying tolerance levels towards BXZs. However, other BXZ- susceptible species are adversely impacted by elevated BXZ levels in crop plants. Thus, considerations for the selection and breeding of wheat genotypes possessing enhanced defensive ability via elevated BXZ contents are discussed. Here, these objectives are reconsidered with a focus on co-evolutionary aspects and their potential impacts on biodiversity in the agroecosystems under study. For future breeding efforts to be successful, it is important to take such potential adverse environmental impacts into account, in combination with an increased focus on enhancing beneficial allelopathic effects within agricultural systems.
... Restricting the definition to crop-weed interference, allelopathy refers here to any direct harmful effect by one plant on another through the production of chemical compounds (allelochemicals) exuded by roots (Rice 1974). Several asteraceae, brassicaceae, fabaceae, poaceae, and polygonaceae crops have been screened for their allelopathic potential against weeds, and differences between species and varieties of a given species have been reported (Wu et al. 1999;Tesio and Ferrero 2010;Jabran et al. 2015). Nevertheless, the allelopathic effect of crops on weeds has mainly been observed in laboratory conditions (Kato-Noguchi and Salam 2013), while field experiments are scarce. ...
... Past reviews on crop allelopathy were usually narrative, broad, and did not focus on allelopathy by living plants and/ or on field experiments (Belz 2007;Narwal and Haouala 2013;Jabran et al. 2015;Jabran 2017;Mwendwa et al. 2018). Moreover, given the difficulty to disentangle them, the discrimination between the effects of allelopathy and competition in field is rarely considered or even discussed. ...
Article
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It is now essential to reduce the negative impacts of weed management and especially herbicide use. Weed-suppressive crop species/varieties hold promise for integrated and sustainable weed regulation. Competition for resources and allelopathy are the two main underlying mechanisms. Unlike competition, which is well studied and established, allelopathy by living crops remains a contentious mechanism. A major difficulty to demonstrate the effects of allelopathy in the field is to dissociate them from those of competition. Here, we systematically and quantitatively review the literature, searching for field-based evidence of the role of allelopathy (by root exudation of living crops) in weed regulation, independently of competition, focusing on studies comparing different varieties of a given crop species. Our critical literature analysis also aims to identify weaknesses and strengths in methodology, providing insights on optimal experimental designs and avenues for future research. Our main conclusions are: (1) in most articles, the role of crop competition is disregarded or not exhaustively studied. Consequently, contrary to authors’ conclusions, it cannot be determined whether weed regulation is due to allelopathy and/or to competition. (2) Few articles provided convincing evidence of the presence/absence of allelopathy in the field. (3) To further investigate allelopathy in the field we recommend to (i) finely characterize crop competition by measuring traits in the field, (ii) assess crop allelopathic potential with complementary experiments in controlled conditions or by quantifying allelochemicals in the field, and (iii) quantify the contribution of each studied trait/mechanism in explaining weed regulation in the field with multiple regression models. In conclusion, the consistent use of the suggested guidelines, as well as alternative approaches (e.g., creation of varieties with deactivated allelopathic functions, development of process-based simulation models), may provide a basis for quantifying the role of allelopathy in the field and, subsequently, for designing weed management strategies promoting weed biological regulation.
... Weed suppression level is directly related to the dose of allelopathic products [47,48]. The higher the amount of plant material used for mulch, the greater the total amount of allelochemicals present in the mulch and released, leading to a higher concentration of allelochemicals into the soil [49][50][51]. Generally, by incorporating a higher amount of crop residues, greater weed suppression was observed. ...
... They provide nitrogen by releasing it into the rhizosphere soil of the tested crop plant. The application of sorghum residues as biological weed management helps in the mineralization of nitrogen and enhances nitrogen availability in the rhizosphere [7,14,50]. However, at later stages of crop growth, the obtainability of nitrogen was improved by mineralization, so this sustained supply of nitrogen was a nonstop source of nutrition for test crops as well as next crops. ...
Article
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The reduction of herbicide use and herbicide-resistant weeds through allelopathy can be a sustainable strategy to combat the concerns of environmental degradation. Allelopathic crop residues carry great potential both as weed suppressers and soil quality enhancers. The influence of sorghum crop residues and water extracts on the weed population, soil enzyme activities, the microbial community, and mung bean crop productivity was investigated in a two-year experiment at the Student Research Farm, University of Agriculture Faisalabad. The experimental treatments comprised two levels of sorghum water extract (10 and 20 L ha−1) and two residue application rates (4 and 6 t ha−1), and no sorghum water extract and residues were used as the control. The results indicated that the incorporation of sorghum water extract and residue resulted in significant changes in weed dynamics and the soil quality indices. Significant reduction in weed density (62%) and in the dry weight of weeds (65%) was observed in T5. After the harvest, better soil quality indices in terms of the microbial population (72–90%) and microbial activity (32–50%) were observed in the rhizosphere (0–15 cm) by the same treatment. After cropping, improved soil properties in terms of available potassium, available phosphorus soil organic matter, and total nitrogen were higher after the treatment of residue was incorporated, i.e., 52–65%, 29–45%, 62–84%, and 59–91%, respectively. In the case of soil enzymes, alkaline phosphatase and dehydrogenase levels in the soil were 35–41% and 52–77% higher, respectively. However, residue incorporation at 6 t ha−1 had the greatest effect in improving the soil quality indices, mung bean productivity, and reduction of weed density. In conclusion, the incorporation of 6 t ha−1 sorghum residues may be opted to improve soil quality indices, suppress weeds, harvest a better seed yield (37%), and achieve higher profitability (306 $ ha−1) by weed suppression, yield, and rhizospheric properties of spring-planted mung beans. This strategy can provide a probable substitute for instigating sustainable weed control and significant improvement of soil properties in the mung bean crop, which can be a part of eco-friendly and sustainable agriculture.
... Weeds are among the major cause of crop yield loss than other categories of agricultural pests [1][2][3]. They are responsible for a large proportion of production costs as a control measure [4,5]. ...
... Natural product-based herbicides such as essential oils and microorganisms offer new approaches as they are eco-friendly and safe bioherbicides to control weeds [2,17]. Essential oils (EOs) are defined as any volatile oil(s) compounds that have strong aromatic and give distinctive odor and the by-products of plants which are commonly known as the volatile secondary metabolites of plants [18]. ...
Article
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Essential (EOs) can be considered as an alternative tool to control weeds, as they are eco-friendly and safe bioherbicides. Based on their herbicidal efficacy against coffee weeds in the prescreening under in-vitro, lath-house and field experimentations, five aromatic plants namely, Cymbopogon citratus, C. martinii, C. winterianus, Eucalyptus citriodora and Thymus schimperi were selected to identify their chemical composition using Gas Chromatography-Mass Spectrometry. The chromatographic analysis revealed the presence of 45 compounds in C. citratus oil dominated with citral (84.86%) from the subclasses of trans-Citral and cis-Citral. Thirty-three compounds were fractionated and identified in C. martinii oil containing geraniol (55.27%), trans-Geranyl acetate (16.82%), (6R,7R)-Bisabolone (7.23%) and trans-.beta.-Ocimene (6.18%) as the main inherited components. The EO from C. winterianus contained 47 compounds with citronellal (31.31%), geraniol (21.24%), citronellol (12.06%) and elemol (6.68%) as the major component. Similarly, a total of 52 compounds were identified from the EO of E. citriodora containing two major compounds namely, citronellal (76.93%) and citronellol (15.24%). The EO from T. schimperi were composed of 32 compounds with carvacrol (72.55%) and thymol (9.12%) as the main constituents. The present finding indicated that herbicidal activities of the EOs might be attributed to their fingerprint components such as citral (3,7-dimethylocta-2,6-dienal), geraniol (2E)-3,7-dimethylocta-2,6-dien-1-ol), citronellal (3,7-dimethyloct-6-enal), citronellol (3,7-Dimethyloct-6-en-1-ol), carvacrol (2-methyl-5-propan-2-ylphenol) and thymol (5-methyl-2-propan-2-ylphenol). Therefore, these bioactive agents have the potential to be used as herbicides to manage weed species in coffee farms for the future.
... In fact, the short half-lives that allelochemicals commonly display in soils, which prevents their accumulation in environmental compartments and subsequent effects on non-target organisms [13], represents one of the reasons why plant allelopathy has received the attention of the scientific community as an ecofriendly tool for weed management [9,14]. Allelochemical-based crop protection strategies can help overcome the negative impact of synthetic herbicides on the environment and human health, and deal with herbicide resistance problems [15,16]. Nevertheless, studies on the environmental factors and different interactions that regulate the behavior of allelochemicals in the soil have progressed slowly, and more work is needed to fill this knowledge gap [14,17]. ...
Article
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Plant monoterpenes have received attention for their ecological functions and as potential surrogates for synthetic herbicides, but very little is known about the processes that govern their behavior in the soil environment, and even less about the possible enantioselectivity in the functions and environmental behavior of chiral monoterpenes. We characterized the adsorption and dissipation of the two enantiomers of the chiral monoterpene pulegone in different soils, and their phytotoxicity to different plant species through Petri dish and soil bioassays. R- and S-pulegone displayed a low-to-moderate non-enantioselective adsorption on the soils that involved weak interaction mechanisms. Soil incubation experiments indicated that, once in the soil, R- and S-pulegone are expected to suffer rapid volatilization and scarcely enantioselective, biodegradation losses. In Petri dishes, the phytotoxicity of pulegone and its enantioselectivity to Lactuca sativa, Hordeum vulgare, and Eruca sativa was species-dependent. Lactuca sativa was the most sensitive species and showed higher susceptibility to S- than to R-pulegone. Biodegradation and volatilization losses greatly reduced the phytotoxic activity of S-pulegone applied to soil, but the addition of a highly-adsorptive organoclay stabilized the monoterpene and increased its phytotoxic effect. Stabilization by adsorption may represent an important mechanism by which the bioactivity of plant monoterpenes in soils can be increased.
... Allelopathic interaction is prevalent in agricultural and natural ecosystems, where it creates a series of ecological and economic problems, such as declines in crop yield and quality due to soil sickness (Huang et al. 2013), failures of forest regeneration (Souto et al. 2000) and the invasion of exotic plant species (Bais et al. 2003). In addition, allelochemicals can be utilized as herbicides for weed control (Jabran et al. 2015). ...
Article
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Allelopathy is mediated by plant-derived secondary metab-olites (allelochemicals) which are released by donor plants and affect the growth and development of receptor plants. The plant root is the first organ which senses soil allelochem-icals this results in the production of a shorter primary root. However, the mechanisms underlying this process remain elusive. Here, we report that a model allelochemical benzoic acid (BA) inhibited primary root elongation of Arabidopsis seedlings by reducing the sizes of both the meristem and elongation zones, and that auxin signaling affected this process. An increase in auxin level in the root tips was associated with increased expression of auxin biosynthesis genes and auxin polar transporter AUX1 and PIN2 genes under BA stress. Mutant analyses demonstrated that AUX1 and PIN2 rather than PIN1 were required for the inhibition of primary root elongation during BA exposure. Furthermore, BA stimulated ethylene evolution, whereas blocking BA-induced ethylene signaling with an ethylene biosynthesis inhibitor (Co 2+), an ethylene perception antagonist (1-methylcyclo-propene) or ethylene signaling mutant lines etr1-3 and ein3eil1 compromised BA-mediated inhibition of root elong-ation and up-regulation of auxin biosynthesis-related genes together with AUX1 and PIN2, indicating that ethylene signal was involved in auxin-mediated inhibition of primary root elongation during BA stress. Further analysis revealed that the BA-induced reactive oxygen species (ROS) burst contributed to BA-mediated root growth inhibition without affecting auxin and ethylene signals. Taken together, our results reveal that the allelochemical BA inhibits root elongation by increasing auxin accumulation via stimulation of auxin bio-synthesis and AUX1/PIN2-mediated auxin transport via stimulation of ethylene production and an auxin/ethylene-independent ROS burst.
... Plants that produce allelopathy properties are known to have a major part in sustainable weed control [9,15]. Many plant species discharge allelochemicals into nature and have organically dynamic aggravates that stifle the development and improvement of other plants [9,16]. ...
Article
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Phytotoxicity including autotoxicity and allelopathy is the immediate or indirect biochemical impact of one organism on the germination, growth, survival, and reproduction of other organisms or improvement of neighbouring plant species through the arrival of substances into the environment. is biological phenomenon e ect might be either growth-enhancing (synergistic) or inhibiting (hostile), contingent upon the chemical substances delivered from donor plants and target species. Allelopathy has been viewed not just as a nature-accommodating way to control unwanted plant spices and biocidal products, but, additionally, a potential explanation for causing autotoxicity in yield. e application of chemical agents to reduce weed infestation may have negative consequences on human health as well as the environment. Plants with allelopathy activities derived from secondary metabolites could be an alternative strategy and have an expected function in sustainable weed biocontrol and boost global agricultural production and food security. us, protecting biodiversity, ensuring food safety, improving food, and nutrient quality, as well as crop production, are urgently needed as population and consumption are increasing. So, the objective of this study is to present recent advancements on phytotoxicity and allelopathic e ect of plant extracts (sorghum, sun ower, rice, and corn), for sustainable food and crop production in agroecosystems.
... The majority of these infochemicals are benefcial to the producing plants, while a few are detrimental. Benefcial volatiles produced by the plant favor the emitter by (i) inducing "allelopathic effects" hampering weed seed germination and growth (Jabran et al., 2015); (ii) acting as "allomones" that repel insect herbivores and provide a direct advantage to the emitter (Tlak Gajger & Dar, 2021;Wahengbam et al., 2021); and (iii) acting as "synomones," which attract arthropod carnivores that devour arthropod herbivore pests damaging the host plant thereby indirectly beneftting the emitter or attract pollinators beneftting both producer and receiver. However, certain volatiles produced by plants attract their herbivore pest or phytopathogen and are thus benefcial to the receivers, but detrimental to the producer and are classifed as "kairomones" (Pathma et al. . ...
... The Solanaceae family is gaining in interest for the allelopathic potential shown by some important members. Rial et al. (2018), for example, investigated the allelopathic traits of tomato (Solanum lycopersicum L.) and identified its major root allelochemicals as the alkaloid-tomatine, the steroid stigmasterol, the furocoumarin bergapten and the strigolactonessolanacol, orobanchol, strigol, etc. Allelopathic crops can be employed to manage weeds in agroecosystems by (i) including them in rotational sequences or (ii) intercropping in close proximity with a cash crop, (iii) cover cropping as living or dead mulches, (iv) crop residue incorporation into the soil and (v) by using their allelochemicals as bioherbicides (Khanh et al. 2005;Jabran et al. 2015). The adoption of allelopathy for weed management is highly flexible, varying site by site depending on the specific characteristics of the context: pedo-climatic conditions, weed species, agricultural practices used, economic constraints and farmer's expectations. ...
Article
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Crop diversification provides an opportunity for farmers to maximize their profits, fulfilling multiple needs, avoid monsoon threats, and make the crop production system sustainable. Inclusion of various pulse/oilseed/vegetables/cereals/medicinal/aromatic crops with sugarcane brings forth cultivation of these crops in irrigated agro-system and improves the yields of component crops. Besides, the component crops improve soil fertility and create a favorable environment for the further growth of sugarcane crops. Sprouting in winter-initiated sugarcane ratoon could be enhanced by adopting fodder legumes such as Indian clover and Egyptian clover. Intercropping vegetables provides an ample opportunity for mid-season income generation and improves profitability. Besides, high-value medicinal and aromatic crops such as tulsi (holy basil), mentha could also be included in the sugarcane-based system. Crop residue management has been recognized as a critical issue in managing the crops in the various cropping systems. Including multiple bio-agents for fast decomposition of crop residues provides scope for managing soil organic carbon through crop residue recycling in the system. Resource use efficiencies, nutrient use, water use, and weed control could be increased by adopting suitable crops in intercropping systems. An integrated farming system involving crop, livestock, and fisheries options could improve farmers' profit besides employment generation in rural India. Recycling of bye products and co-products of other enterprises influences the viability and farmer's profitability of the system. Trash, press mud cake, vinasse, composted bagasse, rhizodeposition of stubble play a significant role in sustaining soil fertility and increasing crop productivity. New emerging crop diversification options, viz., intercropping of rajmash, winter maize, and garlic in autumn cane generate mid-season income and enhance the system's profitability for small and marginal cane growers. Dual-purpose legumes, viz., cowpea, and green gram as intercrops with spring-planted cane increase the pool of soil microbial biomass nitrogen capitalize allelopathic effects and sustain soil health. In the present paper, these issues have been discussed. Due to the adoption of location-specific and farmers-centric systems, farmers' profitability could be increased, providing sustainability to the sugarcane-based systems.
... Our results are at par with the findings of Gella et al., (2013), who reported that different weeds' aqueous extracts significantly reduced seed germination, radical, and plumule biomass of wheat. Furthermore, most weeds and crop species have a phytotoxic effect on the neighboring plants and hence reduced seed germination and growth of the plant (Jabran et al., 2015). Similarly, Abbas et al. (2014) reported the allelopathic effect of many weeds against wheat seed germination. ...
Article
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The biochemical interference between weed-crop for the available resources is one of the most crucial and burning issues for this modern and technologically blessed farming community. Because-of, the early adaptative nature, rapid growth, and fast distribution of weed make it able to inhibit the desired crop growth and reduce the final estimated yields. Thus, our interest was raised in examining the bio-efficacy of some winter weeds against two main agronomic crop germination and seedling growth, and weeds were collected from two different districts D.I. Khan and Peshawar. Wheat variety (Atta Habib) and Chickpea variety (Karak-1) varieties were used in the trial. The experiment was conducted in (2020) in a Completely Randomized Design (CRD) with a factorial arrangement having three replications. We used the following weeds extracts; Trianthema portulacastrum L., Cyperus rotundus L., Plantago lenceolata L., Xanthium strumarium L., Oxalis corniculata L., Eleusine indica L. and distilled water as a control in this study, and introduced them to chickpea and wheat seeds. Our results show that weeds collected from district Dera Ismail Khan were more phytotoxic as compared to Peshawar and greatly inhibited the overall seed germination of wheat and chickpea respectively i.e. 44.53%, and 37.97%. In the case of weeds extract inhibitory effect, the T. portulacastrum was declared more repressive for both crops in terms of germination inhibition and seedling growth retardation. Taken together, the T. portulacastrum weed extract of D.I Khan was highly phytotoxic to inhibit the germination and germination of both crops, therefore, eco-friendly and proper weed management tactics require from the farming community in the early stages or before crop sowing.
... Allelopathy is used to suppress weeds in crop fields. Examples of important allelopathic crops are alfalfa, asparagus, rye, sorghum, rice, sunflower, sugar cane, rapeseed, wheat, among others [11]. ...
Article
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Allelopathy is a harmful effect indirectly or directly produced by one plant to another through the production of chemical substances that enter the environment. Allelopathy has a pertinent significance for systems of ecological, sustainable , and integrated management.
... Allelopathy can be utilized by rotating allelopathic crop in rotation, use of cover crops, mulch, green manuring, intercropping (Jabran et al. 2015;Bertholdsson 2005;Bhowmik and Inderjit 2003). The aqueous extract of sunflower leaves significantly reduced the number of Rumex plants m À2 , however inhibitory effect was concentration dependent (80% vs 100%). ...
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Globally, weeds are the major constraint in wheat and barley production. Weeds competing for crucial resources namely water, nutrient, light and space, reduce wheat yield by 4–40% and even more in herbicide resistance dominated situations. However, reduction in grain yield considerably varies with the type of weed flora, their infestation level, soil and environmental situations as well as the adoption of crop management practices. On a global scale, herbicide resistance has been documented in more than 41countries with 93 weed species (absolute). Higher cases of resistance in weed species is reported from Australia (22), Canada (21), USA (19), France (15) and, China (13). Weeds defying herbicidal site of action are more in ALS and ACCase inhibitors class compared to PSII and synthetic auxins in wheat and barley growing regions. Tillage and cropping system alter weed population by acting as filter and increase weed diversity more under no till and diverse crop rotation as compared to frequent tillage and monoculture system. Chemical weed control is preferred by wheat and barley growers. However, sole reliance on herbicides needs to be discouraged rather it should be integrated with different non-chemical measures such as stale seed bed, zero tillage, diverse crop rotation, cover crops and mulching, competitive cultivars and cultivars blending. The crop resource acquisition can be further increased by higher crop seed rate, narrow spacing, row orientation, early seeding, band placement/point injection of fertilizers, and optimum use of fertilizers. Irreversible loss in weed seed can be improved by enhancing weed seed predation and adoption of weed seed-based destructor that has shown remarkable results in Australia against most of the herbicide resistant weeds. Precision sprays, use of drones for spraying herbicides, robots, soil solarization, and electricity/microwave/laser and heat/fire (flaming/steaming) machines are also evaluated for enhanced weed control where herbicides resistance has narrowed the choice of herbicides. Nano herbicides, seed coating with herbicides for parasitic weed control are also useful in increased weed control efficiency. Wheat and barley area under conservation-based system (CA) is expected to expand in the future and so will be the problem of weeds especially of perennial due to absence of tillage support, more weed diversity and poor efficacy of soil active based herbicides. A computer (vision) aided mechanical chiller and autonomous mower have been found effective to selectively remove emerged weeds in CA system before planting. Moreover, in the near future, weed management is also liable to be more difficult due to increased cases of herbicide resistant weeds and reduced invention of new herbicide chemistry having different sites of action. The changing climate will also further aggravate the problem due to changed weed flora and reduced herbicide efficacy. To provide the wheat and barley growers more alternative herbicidal weed control options as along with simplified weed control, herbicide tolerant crop cultivars to non-selective (glyphosate/glufosinate) or less selective herbicides such as metribuzin and biotechnological tools including CRISPER could be integrated with other fine tuned agronomic practices in wheat and barley cultivation.
... Simultaneously, invasive plants may produce various organic acids, allelopathic substances, and hormones, which can destroy the structure of rhizosphere soil microbial community and interrupt the interaction between the soil community and native plants. This results in successful invasion (Simberloff et al., 2013;Jabran et al., 2015;Zhang et al., 2019). ...
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Plant invasion caused due to various human activities has become a serious problem affecting ecosystem diversity and imposes a burden on the economy. In recent years, there have been increasing studies on the application of biochar (BC) in the field of environmental protection. Invasive plants, which are considered as a kind of hazardous waste biomass, can be used as feedstocks to prepare BC. Consumption of invasive plants for BC preparation can achieve a win-win situation in ecology and resources. This can solve a series of ecological problems caused by invasive plants to a certain extent while also realizing the resource utilization of wastes and bringing considerable economic benefits. Based on previous studies, this paper summarizes the progress of preparing and using invasive plant biochar (IPB). This includes the production, modification, merit and demerit of IPB, its application in improving soil quality, the adsorption of pollutants, application in energy storage, and climate change mitigation potential. It provides a basis for further study of IPB based on the currently existing problems and proposes a direction for future development.
... It consists of sowing/growing multiple crops simultaneously on the same field, with the aim of achieving higher yields [74]. Intercropping ensures a balance with regards to nutrient, light, water, space requirement of crops, and their allelopathic interactions [75], which is achieved by removing the specifically adapted weed species without using herbicides, to preserve the environment. Intercropping can be performed in several ways: by simply mixing two annual crops (wheat with clover/bean), by using alternate rows (simultaneous growing of soybean and maize), by sowing a second crop after the first one has flowered or just before its harvest, and by growing woody vegetation with annual crops [76]. ...
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Herbicide application has long been considered the most efficient weed control method in agricultural production worldwide. However, long-term use of agrochemicals has numerous negative effects on crops and the environment. Bearing in mind these negative impacts, the EU strategy for withdrawing many herbicides from use, and modern market demands for the production of healthy and safe food, there is a need for developing new effective, sustainable, and ecological weed control measures. To bring a fresh perspective on this topic, this paper aims to describe the most important non-chemical weed control strategies, including ecological integrated weed management (EIWM), limiting weed seed bank, site-specific weed management, mechanical weeding, mulching, crop competitiveness, intercropping, subsidiary crops, green manure, and bioherbicides.
... All these reports established a link between H. stoechas biological activity and its high phenolic content. The research of plant-based weeds biocontrol products (botanical bioherbicides) is gaining an increasing interest as an emerging method for weed control in sustainable agriculture, instead of using chemicals with negative environmental impact [9][10][11]. The capacity of one plant to inhibit germination and/or growth of other plants is defined as allelopathy and is based on the production of phytotoxic metabolites (allelochemicals) by the emitting plant. ...
... Likewise, allelopathy can be an important biological force that affects the germination and growth of target plants species, and consequently the population dynamics of plant species and community assembly (Mushtaq et al. 2020c;Zhang et al. 2021). The overall aim of previous research on allelopathy was the reduction of chemical pesticide inputs and consequent environmental pollution, and implementing effective methods for sustainable agricultural development (Han et al. 2013;Jabran et al. 2015;Li et al. 2010;Macías et al. 2003;Mushtaq et al. 2020b). A lot of research has been done to explore the inhibitory potential of different allelopathic crops for the sake of weed management (Bajwa et al. 2020;Farooq et al. 2011;Mushtaq et al. 2019;Nawaz et al. 2014;Sarić-krsmanović et al. 2020). ...
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Previous pasture residues can inhibit the establishment of exotic introduced plant species by exerting allelopathic effects. Concerning this issue, present research work was conducted to investigate the allelopathic potential of dominant native grass species (Lespedeza davurica, Stipa bungeana, and Artemisia capillaris) on the seed germination and seedling growth of exotic plant species (alfalfa and wheat). Different concentrations (2.5%, 5%, and 10%) of residue extracts of native grass species were used in the experiment. Results indicated that the aqueous extracts of A. capillaris and S. bungeana at all concentrations significantly suppressed the seed imbibition, germination potential, germination rate, germination index, seedling height, above and belowground biomass of alfalfa seedlings. Meanwhile, L. davurica did not show any effect on germination indexes but it significantly suppressed the seedling height of alfalfa after two weeks. However, it improved the seed imbibition, seedling height, and biomass of wheat seedlings. The greatest inhibition effect was perceived by A. capillaris followed by S. bungeana extracts. To achieve sustainable agricultural development, it is important to utilize cultivation systems that take advantage of the stimulatory and inhibitory effects of allopathic plants to regulate plant growth and development and to minimize the risk of toxicity caused by allopathic plants species. Graphical Abstract Overall processes of allelopathy and how allelochemicals are derived from the aerial parts of plants and reveals that allelochemical compounds primarily contain phenolic compounds, terpenes, and fatty acids, which influence the seed germination, survival, growth, and development of other plants (e.g., crops or weeds).
... Both salinity and weeds stresses were the most important factors affects barley production in Egypt .From our results we found that weeds interference and salinity levels both cased a huge reduction in barley yield which the weeds stress contributed in decreasing all the studied traits by 10.5, 16.9, 17.9 and 19.1 % reduction in PH, NGS , NT and GY under high salinity levels from 2.33 to 12 dsm -1 . This massive reduction refer to increasing weeds population due the effect of salinity on weeds , which salinity made shock to sensitive plants and led to reduce plants germination rate so this is good condition for different weeds to grew up by its compete with plant these results were in agreement reported by El -Metwally et al. [47] and Hakim et al. [48] whose reported that weeds infestation consider the most significant problematic in causing yield loss under salinity through weeds compete plants for light, water and minerals. Conversely, Kotzaman et al. [49] suggesting that increasing weeds under salinity may be refers to allopathic potential which probably decreases under high salinity through reducing the phytotoxicity of allopathic substances extracts. ...
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In Egypt barley cultivated in new and outlying lands, its yield and quality affected by salinity as abiotic and weeds as biotic stresses which constraints to barley production. Two lysimeter experiments were conducted during seasons 2019/2020 and 2020/2021 winter seasons. In the present work, studied four saline water levels (2.33,4,8 and 12dSm-1) to distinguish the salinity stress tolerance among four of Egyptian barley cultivars (Giza 123, Giza 132, Giza 137 and Giza 138), in addition to find a suitable weed control treatments under salinity stress using three factors in completely randomized design (CRD) with three replications The main findings illustrated that four SSR primers (Bmac 0040, EBmac0871, Bmag 135 and Bmag 770) were generated clear patterns with the high polymorphism (100%); and enable plant breeders to select individual plants based on their marker pattern (genotype) rather than their observable traits (phenotype). Using Bmag 770, amplified specific allele with molecular size 260 bp found in the salt tolerance cultivars (Giza 123 and Giza 137) as a tolerant to salinity. Each of the three studied factors (salinity, weed stress and weed control treatments) individually and their interactions had a significant effect on weed populations and on barley yield economically. The interaction among the factors of the trial and the recommended of the two herbicides (bromoxynil octanoate at 1 L fed-1) +(clodinafop propargyl 2.5% + Pinoxaden 2.5%) at 0. 5 L fed-1) gave the highest means of the characters studied and economic criteria. Therefore, these interactions could be recommended in barley farms to achieve reduction in weed growth under saline conditions and harmful effect of them and boosting barley plantations productivity as well. Economic criteria display that Giza 137 is a good choice cultivar for salinity soil because of its high weed tolerance ability (WTA) and Giza 123 good cultivar for grown in salinity soil but it poor WAT so advised to using by herbicides as weed management to reduce weeds population and increase yield toward increasing farmer's income under salinity soil area.
... Herbicide-resistant weeds, health effects, and environmental concerns are the significant challenges for the continuous use of herbicides to control weeds. In this context, the natural metabolites produced from plants referred to as allelochemicals have the potential to influence the weeds [4] . Allelochemicals are secondary metabolites synthesized in plants mostly from the shikimate and mevalonate pathways, which affect the germination and development of neighbouring plants [5,6] . ...
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Weeds cause significant yield loss in crop plants. The use of herbicides is the economically viable technique for controlling weeds. However, the application of herbicides pollutes the soil, alter the microbial biota and exert a hazardous effect on human and animal health. The continuous use of specific herbicides for controlling weeds leads to the development of herbicide-resistant weeds. The use of natural metabolites from the plants exhibiting allelopathic potential is a novel strategy for sustainable weed management. Eucalyptus tereticornis is an excellent tree species with allelopathic properties. The study aimed to investigate different concentrations (5, 10 and 15%) of aqueous Eucalyptus tereticornis leaf extracts on the most noxious weed Echinochloa crus-galli. The dose-dependent inhibition was recorded in terms of germination percent, seedling growth and vigour. The aqueous leaf extract affected the emergence of the radicle. The inhibitory property of leaf extracts was due to the presence of allelopathic principles, which make Eucalyptus tereticornis as a promising candidate for obtaining bioherbicide.
... (Behbahani 2014). Dodder is an obligate stem parasitic weed that could be a limiting factor in basil production, and its pressure increases dramatically with repeated plantings (Behbahani et al. 2013;Jabran et al. 2015). Several molecular, biochemical, and physiological responses can happen by host plants due to exposure to parasitic weeds (Torres 2010). ...
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Seed priming can improve plant capacity in response to different stresses. This study investigated the effectiveness of seed priming with salicylic acid (SA) and Syrian bean-caper (Zygophyllum fabago L.) shoot residues in promoting the germination and growth of sweet basil (Ocimum basilicum L.) infested by field dodder (Cuscuta campestris Yunck.). Basil seeds were pre-treated with 0.5 mM of SA for 12 h at 25 °C. In the allelopathic plant treatments, 10 g of the Syrian bean-caper powder was mixed into the top 5 cm of pot soil. Among the studied varieties, the Iranian variety had the highest susceptibility to infestation with dodder and application of the Syrian bean-caper residues. Dodder infestation reduced plant biomass, relative water content, leaf area index, soluble proteins, and pigments content, especially in the Iranian variety of basil. By contrast, dodder infestation stress increased proline, soluble sugars, malondialdehyde, superoxide dismutase, peroxidase, and catalase. Application of the Syrian bean-caper residues via reducing the seed emergence of dodder increased the basil plant’s height, dry weight of shoots, leaf area index, relative water content, soluble proteins, and chlorophyll a and b. The positive effects of the Syrian bean-caper residues were higher in the Italian variety of basil than in the Iranian variety. Despite these inhibitory effects of the Syrian bean-caper residues on the dodder infestation, it decreased the basil plant’s height, dry weight of roots, relative water content, soluble proteins, and chlorophyll a and b in the vegetative growth stage. However, the application of SA reduced these inhibitory effects and alleviated the negative impact of the Syrian bean-caper residues on basil plants.
... This method is considered to be an efficacious, cost-effective and environmentally friendly approach to weed control. Allelopathic control of weeds can be applied either as a unique strategy in certain systems, for example in organic production, or in combination with other methods of integrated plant protection (Saxena & Pandey, 2001;Jabran et al., 2015). Another aspect of allelopathy is the applicability of different groups of soil microorganisms and their metabolites for weed control, which offers an important alternative to the use of chemical products (Inderjit, 2005). ...
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This study aimed to examine in vitro allelopathic effects of actinobacterial isolates on seed germination and early seedling growth of velvetleaf (Abutilon theophrasti). Thirtyfive actinobacterial isolates were obtained from soil and compost in different phases of composting. Also, an experiment variant involving the herbicide mesotrione was set in the recommended amount of application, as a reference standard. The experimental results indicate statistically significant differences (p<0.05) between controls and all treatments with actinobacterial isolates regarding seed germination, and radical and shoot length. The highest inhibition (100%) was observed in seed germination and radical length in treatments with the isolates A10 and NOV2, compared to uninoculated starch casein broth (SCB) as control. Shoot length was shown to be the most sensitive parameter, where 100% inhibition was observed in the following treatments with actinobacteria: A010, A017, NOV2, NOV3, NOV4 and NOV5. Actinobacterial isolates showed a higher inhibitory effect on seed germination than treatment with the reference herbicide mesotrione.
... Many weeds are associated with barley threat to crop production and cause considerable economic losses as narrow-leafed weeds especially darnel weed Lolium temulentum [3]. With the aim of reducing reliance on chemical pesticides in weeds control because of their environmental and health damages such as application in inappropriate weather conditions or at the incorrect developmental crop stage, could lead to dangerous environmental consequences, such as the leaching of chemically active compounds into groundwater or residual accumulation in the soil [4], as well as the emergence of resistance to herbicides in weeds [5], For this, the researchers looked for new control methods, use allelopathic substances one of environmentally friendly and effective alternatives to control weeds [6]. Sorghum is one of the crops that has been reported to show allelopathic effects [7], Many allelochemicals have been recorded in different parts of the Sorghum (roots, stems, foliage, and panicle) [8].The farmers often ask about the reasons for the effect of sorghum on subsequent crops without getting a correct scientific answer. ...
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The aim of the study was to investigate phytochemical compounds of aqueous extracts leaves of three growth stages of Sorghum ., and the study the effect of those three aqueous extracts on the darnel weed associated with the barley. The GC-MS method was used to screen the phytochemical compounds of three-stage of growth Sorghum which showed diagnosis a number of compounds depending on the retention time such as Daucol, 13- Octadecenal, and Oleic Acid for growth stage 4-6 leaves, and 2,2-Dimethylpropanoic acid, 1- Eicosanol, and Batilol for growth stage 8-10 leaves, and Hexadecanoic acid, Bis(2-ethylhexyl) phthalate and 1-Docosene for growth stage 12-14 leaves. The results showed significant effects of aqueous extracts leaves of Sorghum in the percentage of control dernal weed where recorded 64.133, 85.360, and 86.427% after 30, 60, and 90 days of treatment at growth stage 12-14 leaves of Sorghum compared with 0.00,0.00 and 0.00 in the control treatment.
... A interferência das plantas daninhas pode promover redução entre 30 e 45% na produtividade da alface quando a competição ocorre nos primeiros estádios de desenvolvimento da cultura (JABRAN et al., 2015). Além disso, afetam a firmeza de suas folhas e, também, o conteúdo de nitrato e caroteno (GIANNOPOLITIS et al., 1989). ...
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The main integrated management techniques for sustainable lettuce cultivation in sloping mountain regions are described throughout the several chapters of this book.
... Emergence inhibition of red rice was increase with the increase in aqueous extract concentrations. Our consequences are in conformity with the observations of Jabran et al. (2015) stated that test species showed significant inhibitory effect on the emergence percentage when compared with lower concentrations, higher concentrations of extract significantly reduced the emergence percentage. Nadeem et al. (2020b) reported that Water extracts of leaf of C. tinctorius at 8% concentration result in lowest E. cruss-galli emergence index. ...
... Under the drought stress condition, phosphorous application can improve the growth of cotton crop [13]. The foliar application of urea and diammonium phosphate is the main source of phosphorous for the improvement of growth and development of cotton crop [60][61][62]. Improvement of fiber in cotton crop under the stress conditions can be obtained by the foliar spray of phosphorous at the boll formation stage [63]. In addition, boll weight and seed cotton yield are increased under stress [64]. ...
... Se concluyó que el efecto de estos residuos es altamente dependiente de la concentración usada y de la especie vegetal receptora; sin embargo, bajo las condiciones de este estudio se obtienen inhibiciones significativas sobre el crecimiento de las arvenses al incorporar una dosis del 2% de estos.Palabras clave: arvenses, alelopatía, biocontrol.INTRODUCCIÓNEn un sistema de producción agrícola, el componente vegetal "arvense" es de gran importancia económica, debido a los diferentes daños directos e indirectos que ocasionan, entre los que destacan la competencia por recursos, la actividad hospedera de plagas y enfermedades y la exudación de compuestos aleloquímicos inhibitorios. A nivel mundial se estima que las pérdidas ocasionadas por la presencia de arvenses en los principales cultivos se encuentran alrededor del 30%(Jabran et al., 2015). En el cultivo de aguacate, dadas las extensas áreas de siembra y la eventual escasez de mano de obra, las medidas de manejo de estas poblaciones se limitan a la aplicación de herbicidas, y en ocasiones de forma indiscriminada. ...
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El desarrollo de los árboles frutales y la calidad de fruto están en función de las prácticas de manejo y la presencia de polinizadores. La polinización es considerada como un servicio ecosistémico esencial para la producción de alimentos. Se identificó la riqueza y abundancia de insectos polinizadores y aspectos morfológico-productivos de manzano (Malus domestica Borkh) cv “agua nueva dos”, en un sistema milpa intercalada en árboles frutales (MIAF) en la región de Huejotzingo, Puebla. La colecta de insectos polinizadores se realizó durante la floración de los manzanos (entre febrero y abril de 2018) utilizando dos métodos de captura complementarios: platos trampa y red entomológica. Se registró la altura y diámetro de los árboles, y el número, peso y diámetro de frutos. Se obtuvo un índice de biodiversidad Shannon de 1.6 e índice de Simpson de 0.48 de acuerdo con los insectos colectados, siendo A. mellifera la especie dominante. Existe una correlación fuerte entre número de frutos por árbol y diámetro del árbol (r=0.998) y diámetro del fruto y peso del fruto (r=0.919). Es necesario estudiar si la efectividad cuantitativa de A. mellifera en la polinización resulta en una efectividad cualitativa, al igual que en otros insectos encontrados, como los empídidos, de particular interés por su abundancia en el sistema MIAF.
... La plupart des chercheurs l'évaluent à moins de 0,3 %, ce qui veut dire que 99,7 % des substances déversées s'en vont ailleurs [12]. En outre, une utilisation répétée d'herbicides chimique, favorise la sélection d'espèces non sensibles, devenant de plus en plus dommageables aux cultures d'intérêts [13] et a des effets négatifs sur la santé humaine, les animaux et sur l'environnement [14]. C'est dans ce contexte, que cette étude a été initiée, dans le but de mieux faire connaître la flore adventice en cacaoculture et d'apprécier la nuisibilité de ces espèces d'adventice, ce qui permettra la mise au point de stratégie de lutte autre que les herbicides plus respectueux de l'environnement. ...
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Cette étude a été initiée dans le but de caractériser la flore adventice en cacaoculture afin d'apprécier la nuisibilité de ces espèces d'adventice. À cet effet, des relevés phytosociologiques ont été réalisés dans 18 plantations dans le département d'Adzopé. Les résultats révèlent que la flore adventice du cacaoyer dans cette zone est constituée de 195 espèces réparties dans 146 genres et 52 familles. La classe des dicotylédones avec 80 % des espèces sont les plus abondants de cette flore. Les familles des Rubiaceae, Fabaceae, Apocynaceae et Poaceae sont les plus représentées. On a une prépondérance des arbustes (37 %) suivis des lianes (33 %). En ce qui concerne la répartition biogéographique, les espèces Guinéo-Congolaise (GC) et Soudano-Zambézienne (GC-SZ) sont majoritaires avec respectivement 72 % et 22 % de la flore adventice. La zone d'étude est floristiquement homogène. Une classification des adventices en fonction de leur agressivité a mis en évidence, uniquement des espèces d'adventice peu agressive ou adventice majeur potentielle, qui sont quand-même à surveiller de près. Ce sont par exemple, Hypum cupressiforme (Csf = 2,51), Asystasia calycina (Csf = 1,71), Dioscorea smilacifolia (Csf = 1,06), Albizia adianthifolia (Csf = 1,72), Funtumia africana (Csf = 1,71), Terminalia superba (Csf = 1,71), Trichilia monadelpha (Csf = 1,48). Les résultats de cette étude mettent alors en exergue la forte présence de mauvaises herbes susceptibles d'être problématique au
... Currently, many allelochemicals have been developed as herbicides [3], bacteriostasis [4], and algal inhibitory agents [5], representing new methods for biological controls in agricultural ecosystems and marine ecosystems. Jabran et al. [6] demonstrate that 34% of yield losses of major food crops worldwide are caused by weeds, which can significantly affect the growth and development of crops and are more harmful than diseases and insect pests. Compared to chemical herbicides, applying allelopathic practices during weeding can avoid environmental pollution and the genetic variation of weed resistance. ...
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Background Allelopathy is expressed through the release of plant chemicals and is considered a natural alternative for sustainable weed management. Artemisia argyi ( A. argyi ) is widely distributed throughout Asia, and often dominates fields due to its strong allelopathy. However, the mechanism of A. argyi allelopathy is largely unknown and need to be elucidated at the physiological and molecular levels. Results In this study, we used electron microscopy, ionomics analysis, phytohormone profiling, and transcriptome analysis to investigate the physiological and molecular mechanisms of A. argyi allelopathy using the model plant rice ( Oryza sativa ) as receptor plants. A. argyi water extract (AAWE)-treated rice plants grow poorly and display root morphological anomalies and leaf yellowing. We found that AAWE significantly inhibits rice growth by destroying the root and leaf system in multiple ways, including the integrity of ultrastructure, reactive oxygen species (ROS) homeostasis, and the accumulation of soluble sugar and chlorophyll synthesis. Further detection of the hormone contents suggests that AAWE leads to indole-3-acetic acid (IAA) accumulation in roots. Moreover, ionomics analysis shows that AAWE inhibits the absorption and transportation of photosynthesis-essential mineral elements, especially Mg, Fe, and Mn. In addition, the results of transcriptome analysis revealed that AAWE affects a series of crucial primary metabolic processes comprising photosynthesis in rice plants. Conclusions This study indicates that A. argyi realizes its strongly allelopathy through comprehensive effects on recipient plants including large-scale IAA synthesis and accumulation, ROS explosion, damaging the membrane system and organelles, and obstructing ion absorption and transport, photosynthesis and other pivotal primary metabolic processes of plants. Therefore, AAWE could potentially be developed as an environmentally friendly botanical herbicide due to its strong allelopathic effects.
... Benzer şekilde aynı durum kendisinden sonra o alanda çıkan bazı yabancı otlar içinde geçerli olmaktadır. Bu özelliği sayesinde yabancı otların kontrolü içinde kullanılabilmektedir. Yani entegre bir yabancı ot kontrolü için sorgum bitkisi, etkili kullanılabilen bitkilerden birisi olarak karşımıza çıkmaktadır [31]. Özellikle Sorghum bicolor'un içerdiği sorgoleone maddesi sayesinde yabancı ot kontrolü için önemli bitkilerden birisi olduğu çeşitli araştırmalarda da bildirilmiştir. ...
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Z Bitkisel üretimin yapıldığı alanlarda görülen hastalık, zararlı ve yabancı otlar önemli düzeyde ürün kayıplarına sebep olmaktadır. Tüm Dünyada artan çevre bilinci sebebiyle tarımsal mücadelede kullanılan sentetik ilaçların insan sağlığı ve çevreye olan olumsuz etkilerini gidermek için yabancı otlarla kimyasal mücadele yerine, alternatif uygulamaların devreye sokulması önem kazanmıştır. Bu alternatif yöntemlerden biri yabancı otlar üzerinde allelopatik etkiye sahip, doğal kaynaklı bileşiklerin kullanılmasıdır. Sorgumun, içerdiği ikincil metabolit bileşikler sayesinde yabancı otların mücadelesinde kullanılabilme potansiyeli olduğu bilinmektedir. Sorgumun su ektraktının hem yabancı ot hem de kültür bitkisi gelişimi üzerine etkilerini belirlemek amacıyla yapılan bu çalışmada; Gözde 80, Erdurmuş ve Aldarı sorgum çeşitleri kullanılmıştır. Sorgum çeşitlerinin, üzerine allelopatik etkisinin belirleneceği kültür bitkisi olarak; buğday, çim, mısır, yem bezelyesi, yabancı ot olarak ise; semizotu ve kırmızı köklü horozibiği bitkileri kullanılmıştır. Sorgum çeşitlerinden elde edilen %3 ve 5'lik su çözeltileri, belirlenen kültür bitkisi ve yabancı otlar üzerine uygulanmış ve çimlenme oranı, kök ve sürgün boyu, yaş ve kuru ağırlık gözlemleri alınmıştır. Sonuç olarak; özellikle Erdurmuş çeşidinin bitkisel su ekstraktlarının buğday, kırmızı köklü horozibiği ve semizotunda çimlenmeyi kontrol grubuna göre önemli düzeyde düşürdüğü, ayrıca mısır bitkisinin çimlenme parametrelerinden kök ve sürgün uzunluğunu önemli derecede gerilettiği belirlenmiştir. ABSTRACT Diseases, pests and weeds are seen in the areas where crop production is carried out causing significant crop losses. Due to the increasing environmental awareness all over the world, it has become important to use alternative practices instead of chemical control against weeds in order to eliminate the negative effects of synthetic drugs used in agricultural struggle on human health and the environment. One of these alternative methods is the use of naturally sourced compounds with 1* Sorumlu yazarın
... Visible effects of allelochemicals on the growth and development of plants includes inhibited or retarded germination rate, darkening and swelling of seeds, reduced root and shoot growth or coleoptile extension, swelling or necrosis of root tips, discoloration of roots, lack of root hairs, reduction in dry matter accumulation and reproductive capacity (Bhadoria, 2011). Jabran et al. (2015) reported that use of allelopathic cover crops, allelopathic intercrops, inclusion of allelopathic crops in rotation and the use of allelopathic plant residues as mulches have an important role in the management of weeds in sustainable agricultural systems. ...
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Millets are the traditional staple food of dry land regions and have the potential to contribute substantially for food, fodder and the nutritional security. The millets are relatively poor competitors against weeds especially during the early growth stages due to their slow initial growth and wider spacing. Yield loss due to weeds in millets varies from 5 to 94 per cent depending on climatic, edaphic and biotic factors. Weeds compete with crops for nutrients, soil moisture, sunlight and space when they are limiting, resulting in reduction in yield, quality and increased cost of production. The objective of this paper is to review the research that have been conducted pertaining to various aspects of weed management in millets. The literature suggests that instead of relying on any single method of weed control, all the feasible methods are to be integrated for the effective and sustainable management of weeds in millets. Integrated weed management can effectively overcome the problems of weed shift and development of resistance in weeds and reduce the weed seed bank and manage the weeds below the economic threshold level to avoid any economic loss.
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Cymbopogon winterianus is an aromatic plant of Poaceae that has many biological activities, including insecticidal, bacteriostatic, and anti-inflammatory activities. It is widely used in the food, medicine, and cosmetics industries. The aim of this study was to investigate the gastric toxicity of citronella essential oil and its main component, geraniol, to Drosophila melanogaster larvae. C. winterianus was produced in Dongxing City (Guangxi Province, China), and its essential oil was obtained by steam distillation. The chemical composition of citronella essential oil was analyzed using gas chromatography-mass spectrometry (GC-MS). The gastric toxicity of citronella essential oil and its main components against the second-instar larvae of D. melanogaster was studied. The GC-MS analysis identified 63 volatile components, of which 19 chemical constituents had a relative content of more than 0.50% each in the citronella essential oil, accounting for 92.89% of the total essential oil. The constituents mainly include geraniol (18.88%), citronellal (16.95%), elemenol (14.08%), and citronellol (12.57%). These results are different from the reported results in terms of species and content. The underlying reasons for the differences could be attributed to the variety, production area, and harvest time. The results of gastric toxicity showed that the LC50 values of citronella essential oil and geraniol were 40.06-48.51 and 7.82-10.42 μL/mL, respectively, in treated D. melanogaster larvae. The geraniol showed good gastric toxicity, and the corrected mortality was 100% at 20.00 μL/mL when D. melanogaster larvae were treated for 24 h. Both citronella oil and geraniol showed gastric toxicity to D. melanogaster larvae, but the gastric toxicity of geraniol was significantly higher than that of citronella oil. Thus, geraniol, from citronella (C. winterianus) essential oil, may have value for control of D. melanogaster and may be developed into a plant-derived insecticide.
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Plant secondary metabolites (PSM) are small molecules of organic compounds produced in plant metabolism that have various ecological functions, such as defense against pathogens, herbivores, and neighboring plants. They can also help to reduce abiotic stresses, such as drought, salinity, temperature, and UV. This chapter reviewed the ecological functions of the PSM and how people utilize these metabolites to reduce crop biotic and abiotic stresses in agriculture. Specific topics covered in this review are (1) extraction of PSM from plant parts and its application on crops; (2) screening of crop/cover crop germplasms for high PSM content and with resistance to pathogens, herbivores, and/or neighboring plants; (3) regulation of PSM biosynthesis (including plant hormones and defense activators) to increase plant readiness for defense; (4) transcriptome and genome technology improvements in the last decade leading to valuable tools to characterize differential gene expression and gene composition in a genome, and lineage-specific gene family expansion and contraction. In addition, there is a critical need to understand how the biosynthesis and release of allelochemicals occur. Filling this knowledge gap will help us to improve and encourage sustainable weed control practices in agriculture.
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Aim. To establish the main composition of allelochemicals and the activity of their aqueous extracts from sweet sorghum seeds – hybrids with high and medium sugar content ‘Sugargraze ARG’ (Argentina), ‘Sioux’ (USA) and ‘Ananas’ (Ukraine) on germination energy and seed germination of test crops (peas, clover). Methods. Allelopathic, physiological-biochemical, agrochemical and statistical methods were used. The allelopathic activity of extracts (water-soluble) from the seeds of the studied sorghum hybrids was determined by direct biotesting. The chemical component of allelopathically active substances was determined by extraction. Results. Aqueous extracts from sweet sorghum seeds of hybrids ‘Sugar­graze ARG’, ‘Sioux’ and ‘Ananas’ were found to have a high content of phytochemicals and at a concentration of 40 and 50% inhibited the germination energy and germination of pea and clover seeds by an average of 15–42%. Aqueous extracts of concentrations from 5 to 30% of the studied hybrids showed a stimulating and tolerant effect on the quality of seeds of biotest crops of clover and peas, as germination rates were at the level of control or 5–7% higher, i.e. showed the least allelopathic activity. Conclusions. Sweet sorghum seeds have a sufficient number of allelochemicals, the specificity of which depends on varietal differences in the content of phenolic compounds (glycosides), tannins, acids and carbohydrates. The activity of the allelochemicals extracted from the seeds was weak in the stimulating effect and high in the inhibitory one. For water-soluble extracts from sorghum seeds, a sharp decrease in the manifestation of allelopathic activity is characteristic when their concentration decreases to 5–20%. Studies of water-soluble extracts of seeds at a concentration of 30–50% showed their high overall allelopathic activity, which was manifested in the inhibition of seed germination of biotest crops by 42%. The species-specific action of allelochemicals must be taken into account when sowing multicomponent fields, crop rotation planning, and the use of sweet sorghum as green manure.
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Wheat allelopathy can be manipulated for sustainable weed management in wheat based cropping systems. Bioassays were conducted to quantify the allelopathic potential of 35 indigenous wheat genotypes against germination and seedling growth of wild oat (Avena fatua L.). Foliar application of aqueous extracts of wheat straw, surface mulching and incorporation of wheat straw of different genotypes were employed for bioassays study. Results revealed the suppressive allelopathic activity of different wheat genotypes manifested in the form of impaired germination and retarded seedling growth of wild oat. A highly significant genotypic variation in allelopathic potential was observed for different traits. Germination of wild oat was decreased by 10-84% over control by different wheat genotypes. Likewise, over 70% reductions in seedling root and shoot dry weight of wild oat was also observed in V6007. Wheat genotypes viz. V6007, AS 2000, V6111, V6034, V4611, V7189, Uqab 2000, Chanab 2000, Bhakkar 2002, Pak 81 and Rohtas 90 showed strongly inhibitory allelopathic activity against seedling growth of wild oat. V6007 exhibited highest suppression of wild oat. These studies confirm the suppressive allelopathic potential of indigenous wheat genotypes against wild oat that needs further to be explored under natural conditions.
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Reduced Herbicide Doses Used Together with Allelopathic Sorghum and Sunflower Water Extracts for Weed Control in Wheat Water extracts from allelopathic crops possess the potential to control weeds effectively, especially when used in combination with reduced rates of herbicides. Label doses of different herbicides and their seventy percent reduced doses, were combined with 18 l/ha each of allelopathic sorghum and sunflower water extracts (WE). This combination was sprayed 30 days after sowing (DAS) for weed control in wheat ( Triticum aestivum ). Maximum reduction in total weed density and dry weight over the control, was recorded in a field sprayed with mesosulfuron + idosulfuron (Atlantis 3.6 WG) at 14.4 g active substance (a.s.)/ha. However, sorghum + sunflower WE each at 18 l/ha combined with doses which had been reduced by 70% of mesosulfuron + idosulfuron (Atlantis 12 EC at 36 g a.s./ha), or metribuzin + phenoxaprop (Bullet 38 SC at 57 g a.s./ha) or mesosulfuron + idosulfuron (Atlantis 3.6 WG at 4.32 g a.s./ha), reduced total weed dry weight by more than 90%, over the control. Sorghum and sunflower water extracts each at 18 l/ha combined with metribuzin + phenoxaprop (Bullet 38 SC at 57 g a.s./ha) produced a maximum number of productive tillers, spikelets per spike, number of grains per spike, biological yield and grain yield. Moreover, this treatment was the most economical along with having the maximum net benefits. The results suggested that weeds can be controlled in wheat, for a higher yield, when a 70% reduced herbicide dose is used in combination with allelopathic sorghum and sunflower water extracts.
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Allelopathy is the process whereby an organic chemical (allelochemical) released from one plant influences the growth and development of other plants. Allelochemicals produced by specific rice (Oryza sativa L.) cultivars have potential to manage barnyard grass (Echinochloa crus-galli L.), a major yield-limiting weed species in rice production systems in Asia and North America. In this study, isolation and identification of an allelopathic compound, N-trans-cinnamoyltyramine (NTCT), in a Vietnamese rice cultivar 'OM 5930' was accomplished through bioassay-guided purification using reversed-phase liquid chromatography coupled with spectroscopic techniques, including tandem mass spectrometry, high resolution mass spectrometry, as well as one-dimensional and two-dimensional (1)H NMR and (13)C NMR spectroscopy. The identified compound, NTCT is considered a β-phenylethylamine. NTCT inhibited root and hypocotyl growth of cress (Lepidium sativum L.), barnyard grass and red sprangletop (Leptochloa chinensis L. Nees) at concentrations as low as 0.24μM. The ED50 (concentration required for 50% inhibition) of NTCT on barnyard grass root and hypocotyl elongation were 1.35 and 1.85μM, respectively. Results further demonstrated that mortality of barnyard grass and red sprangletop seedlings was >80% at a concentration of 2.4μM of NTCT. By 20days after transplanting, 0.425nmol of NTCT per OM 5930 rice seedling was released into the culture solution. With concentrations of 42μgg(-1) fresh weight, production of NTCT in intact rice plants can be considered high. These findings suggest that developing plants of Vietnamese rice cultivar OM 5930 release NTCT and may be utilized to suppress barnyard grass in rice fields. The potency of NTCT may encourage development of this compound as a bio-herbicide.
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The effects of Chenopodium murale root exudates, applied as phytotoxic medias (PMs), were tested on Arabidopsis thaliana and Triticum aestivum. The effects of PMs, where wild-type roots (K), hairy roots derived from roots (R clones) or from cotyledons (C clones) were cultured, were different. K medium suppressed Arabidopsis germination, while other PMs reduced root and leaf elongation and the number of rosette leaves. R media were more phytotoxic than C media. Treatment of Arabidopsis with R8 down-regulated expression of core cell cycle genes: cyclin-dependent kinase (CDK) A1;1, four B-class CDKs, and cyclins CYCA3;1, CYCB2;4, CYCD4;2 and CYCH1 in root and shoot tips. Only CYCD2;1 transcript was elevated in treated shoots, but down-regulated in roots. Wheat Ta-CDC2 and Ta-CYCD2 genes showed the same expression profiles as their Arabidopsis counterparts, CDKA1;1 and CYCD2;1. PMs also caused increase of antioxidative enzyme activities in both plants. Exposure of Arabidopsis to PMs induced one catalase isoform, but repressed another, resulting in no net change of catalase activity. Wheat seedlings treated with PMs had catalase activity significantly elevated in all treatments, particularly in shoots. In both plants, PMs induced the activity of different peroxidase isozymes and total peroxidase activity. Both plants responded to phytotoxic treatments by induction of CuZn-superoxide dismutase. Thus, the phytotoxicity of C. murale root exudates is, at least partially, based on down-regulation of the cell cycle regulators and on generation of oxidative stress in the affected plants. We propose that C. murale root exudates should be considered as means of biological weed control.
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Field experiments were conducted to compare the effects of allelopathic sorghum cultivars ‘Enkath’ and ‘Rabeh’ at three planting densities (6.6, 13.3 and 26.6 plant m−2) on weed growth and sorghum yields in 2009 and 2010. Sorghum planting densities suppressed average weed population by 26–42% and average weed biomass by 46–57% compared with weedy check in 2009. A similar trend in the reduction in weed population and weed biomass was observed in 2010. Planting densities at 6.6, 13.3 and 26.6 plant m−2 significantly suppressed average weed population by 26, 31 and 42% and average weed biomass by 88, 91 and 96% compared with weedy check, respectively, during 2009. A similar trend in effect was also recorded during 2010. Enkath cultivar reduced average weed density and dry biomass by 25 and 44% during 2009 and by 23 and 30% in 2010 compared with Rabeh cultivar. Root exudates of Enkath inhibited more weed growth than Rabeh. Increased planting density significantly increased average grain yield of sorghum. The highest grain yield of sorghum (12.68 t ha−1) was recorded in plots in which the planting density was 26.6 plant m−2.
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Environmental pollution, development of herbicidal resistance among weeds and health hazards due to non judicious use of herbicides has forced the researchers to make concerted efforts to develop alternate weed control strategies. In that scenario, use of allelopathic plant water extracts with reduced rates of herbicides to control weeds in arable crops has become an attractive option for the researchers. The present study was conducted to investigate the possible effects of allelopathic plant water extracts in combination with reduced doses of atrazine for weed control in maize. Atrazine was applied @ full dose (500 g a.i. ha -1), ½ dose (250 g a.i. ha -1), ⅓ dose (167 g a.i. ha -1) and ¼ dose (125 g a.i. ha -1) alone; reduced doses (½, ⅓ and ¼) of herbicide were applied in combination with 20 L ha -1 of allelopathic plant water extracts of sorghum, brassica, sunflower and mulberry; 20 L ha -1 of allelopathic plant water extracts of sorghum, brassica, sunflower and mulberry was applied alone; while weedy check was also maintained as control. The four levels of atrazine showed 65-81% suppression of weeds density and weeds dry weight over control (weedy check), while allelopathic plant water extracts showed 70-75% suppression of weeds density and dry weight when used in combination with half and 1/3 rd dose of atrazine over control. Nonetheless, 49%, 36% and 31% more grain yield was obtained where full dose (alone) and half and ⅓ dose of atrazine in combination of allelopathic plant water extract were applied, respectively over control. In conclusion, allelopathic plant water extracts can be utilized with reduced doses of herbicide to keep environment healthy and efficient weed control in maize. Formulation of allelopathic water extracts into a handy product would facilitate their use for environment friendly weed management.
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Background and Aims Soil micro-circumstance and biological stress resistance were studied to validate our hypothesis that the allelopathic potential that was enhanced by breeding resulted partially from rhizophere microbes associated with the different varieties. Methods The rhizosphere soils from four wheat genotypes with different allelopathic potential were collected so as to compare their soil micro-environments and bio-pressure tolerances. Results The levels of these three categories such as bacteria, fungi, and actinomycetes ranged among 1.54–26.59 × 106, 0.43–4.12 × 104, and 1.36–18.25 × 105 CFU/g soil, respectively. Wheat 22 Xiaoyan with greater allelopathic potential had higher levels of microorganisms than the other three genotypes having weak allelopathy. The soil microbial carbon and nitrogen analyses suggested that wheat could create an active microhabitat with high activities of key soil enzymes such as urease, catalase, sucrase, and dehydrogenase. Using the approximate concentrations detected in wheat rhizosphere soils, the leachates of all four wheat materials significantly inhibited the growth of the weed Descurainia sophia and take-all pathogen Gaeumannomyces graminis var. Tritici. Conclusions Wheat exudates provided carbon and nitrogen resources for the relevant microorganism. Meanwhile, the rhizosphere soil microbes contributed to allelopathic potential of wheat by positive feedback.
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To reduce the need for seasonal inputs, crop protection will have to be delivered via the seed and other planting material. Plant secondary metabolism can be harnessed for this purpose by new breeding technologies, genetic modification and companion cropping, the latter already on-farm in sub-Saharan Africa. Secondary metabolites offer the prospect of pest management as robust as that provided by current pesticides, for which many lead compounds were, or are currently deployed as, natural products. Evidence of success and promise is given for pest management in industrial and developing agriculture. Additionally, opportunities for solving wider problems of sustainable crop protection, and also production, are discussed.
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Fundamentals of Weed Science, Fifth Edition, provides the latest information on this constantly advancing area of study. Placing weed management in the largest context of weed research and science, the book presents the latest advances in the role, control and potential uses of weed plants. From the emergence and genetic foundation of weeds, to the latest means of control and environmental impact, the book uses an ecological framework to explore the role of responsible and effective weed control in agriculture. In addition, users will find discussions of related areas where research is needed for additional understanding. Explored topics include the roles of culture, economics and politics in weed management, all areas that enable scientists and students to further understand the larger effects on society. Completely revised with 35% new content Contains expanded coverage of ethnobotany, the specific identity and role of invasive weed species, organic agriculture, and herbicide resistance in GM crops Includes an emphasis on herbicide resistance and molecular biology, both of which have come to dominate weed science research Covers all traditional aspects of weed science as well as current research Provides broad coverage, including relevant related subjects like weed ecology and weed population genetics.
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