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Effect of biofertilizer containing Thiobacillus bacteria along with different levels of chemical sulfur fertilizer on growth response and photochemical efficiency of small radish plants (Raphanus sativus L. var. shushtari) under greenhouse conditions

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... Norank_f__norank_o___SBR1031 mainly appeared in the heterotrophic denitrification system with carbon source utilization, and the contents were 11.62% and 10.52%, respectively, indicating that the system contained a small carbon source with a small portion of heterotrophic denitrification. Thiobacillus was considered as the main autotrophic denitrifying bacterium [46,47]. It was found that Thiobacillus was the dominant species in sulfur-based denitrification, and the contents of Thiobacillus in the simulated and actual wastewater were 3.69% and 5.55%, respectively. ...
... These two microorganisms, Trichococcus and ank_o___SBR1031 mainly appeared in the heterotrophic denitrification system with carbon source utilization, and the contents were 11.62% and 10.52%, respectively, indicating that the system contained a small carbon source with a small portion of heterotrophic denitrification. Thiobacillus was considered as the main autotrophic denitrifying bacterium [46,47]. It was found that Thiobacillus was the dominant species in sulfur-based denitrification, and the contents of Thiobacillus in the simulated and actual wastewater were 3.69% and 5.55%, respectively. ...
... Secondly, they provided a favorable location for the microorganisms to attach to the surface ank_o___SBR1031 mainly appeared in the heterotrophic denitrification system with carbon source utilization, and the contents were 11.62% and 10.52%, respectively, indicating that the system contained a small carbon source with a small portion of heterotrophic denitrification. Thiobacillus was considered as the main autotrophic denitrifying bacterium [46,47]. It was found that Thiobacillus was the dominant species in sulfur-based denitrification, and the contents of Thiobacillus in the simulated and actual wastewater were 3.69% and 5.55%, respectively. ...
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Macrotyloma uniflorum (horse gram) is considered an under-utilized legume crop despite its nutritional and medicinal values. In India, it has wide acceptance among farming communities. This investigation emphasized on the possible application of two endosymbionts (Bacillus sp. AS03 and Rhizobium sp. AS05) of horse gram cultivated on Cr (VI)-contaminated soil. The photosynthetic performance (PIϕ) of Cr treated plants co-inoculated with AS03 and AS05 was significantly improved compared with non-inoculated Cr treated plants based on photosynthetic yield, which was evidenced from the rise in the fluorescence at I–P transient and rate of photosynthesis (pN), indicating synergistic action between plant and bacteria (AS03 and AS05). The smooth electron transport from PS II to PS I was achieved in the Cr stressed plants inoculated with both the bacterial strains. The detrimental effects of Cr toxicity on the root tips were also minimized with bioinoculation as revealed from mitotic index. Plants with dual inoculation of AS03 and AS05 had significantly lesser chromosomal aberration in the roots. Dual inoculation biochar or seed inoculation have beneficial impact on the plant photosynthetic performance along with improved growth of roots in plants treated with Cr (VI). The results of the current work suggest the possitive effect of dual inoculation of Cr tolerant endosymbionts, Bacillus sp. (AS03) and nodulating Rhizobium sp. (AS05), in reducing cytological as well as physiological stress of plants in Cr (VI) contaminated soil.
Article
The Contamination of agricultural soils with Arsenic (As) is a significant environmental stress that restricts plant growth, metabolism, and productivity worldwide. The present study examined the role of sulfur (S⁰) in protecting Brassica napus plants from Arsenic (As) toxicity. Arsenic (100, and 200 mg As kg⁻¹ soil) in soil caused detrimental effects on five Brassica napus cultivars (Neelam, Teri-Uttam Jawahar, Him Sarson, GSC-101, and NUDB 26–11). The As toxicity inhibited the growth and photosynthesis indices in all cultivars with more deterioration effects in NUDB 26–11. Plant absorption and uptake of As caused the generation of oxidative injury by accumulating the reactive oxygen species (ROS), which simultaneously decreased the plant defence capability and ultimately the photosynthesis. Application of sulfur (S⁰, 100 or 200 mg S kg⁻¹ soil) alleviated the negative impacts and toxicity of As on the photosynthesis and growth matrices of plants, especially under high S level. S⁰ also boosted the antioxidant potential of plants and toned-down lipid peroxidation and ROS aggravation such as superoxide anion (O2.-) and H2O2, hydrogen peroxide, in As affected plants. In general, S⁰ at 200 mg kg⁻¹ soil more perceptibly increased the functionality of antioxidant enzymes, and non-enzymatic antioxidants, metal chelators and non-protein thiols. Further amendment of soil with S⁰ at fifteen days before seed sowing affected by As-induced toxic effects (added to soil at the time of sowing) considerably intensified the endogenous hydrogen sulfide (H2S) content and its regenerating enzymes D-cysteine desulfhydrase (D-CD) and L-cysteine desulfhydrase (L-CD) that further strengthened the defense capability of plants to withstand As-stress. Our results suggest the role of H2S in the S-induced defense operation of the B. napus plants in restraining As toxicity. The current study shows that S⁰ as a source of S might be used to promote the growth of B. napus plants in polluted agricultural soils.
Article
The effectiveness of iron is reduced in saline conditions, which can easily lead to iron deficiency and inhibit photosynthesis in rice. In this study, 4-week-old Fe-deficient rice seedlings were treated under saline sodic stress (50 mM) to different concentrations (0, 0.2%, 0.4%, 0.8%, 1.6%, and 3.2%) of foliar iron fertilizer (FeEDDHA). Differences in prompting fluorescence and the MR820 signal of rice leaves after 7 days of treatment were probed using the JIP-test. The results show that the performances of the two rice varieties were in general agreement. Under iron deficiency and soda salinity stress conditions, rice growth was inhibited, and the pigment content, specific energy flux, quantum yield, performance of the active PSII reaction center (PIABS) and the oxidation (Vox) and reduction rates (Vred) of PSI were reduced. These indicators first increase and then decrease with increasing iron fertiliser concentrations. The best results were obtained with the Fe3 treatment (0.8%). Fluorescence parameters such as the relative variable fluorescence (WK and VJ) and the quantum yield of energy dissipation (φDo) showed opposite trends. This suggests that iron deficiency/excess and soda saline stress disrupt the electron and energy transport in the photosystem. Appropriate iron fertilization concentration can repair the photosynthetic electron transport chain, improve electron transport efficiency and promote balanced energy distribution. Therefore, we suggest that moderate amounts of Fe are beneficial for improving the electron and energy transport properties of the photosystem, while spraying high concentrations of Fe fertilizer has a negative effect on improving salt tolerance in rice.
Article
During this study, the bioremediation potential of zinc-oxide nanoparticles (ZnO-NPs) and PGPR mixed biofertilizer (BF) on maize plants under induced arsenic (As) stress of 50 ppm and 100 ppm was investigated. The treated plants showed increased As resistance to mitigate the adverse effects of stress by enhancing fresh and dry biomass, relative water content, protein content, soluble sugars, proline content, enzymatic antioxidant defense mechanisms including catalase activity (CAT), peroxidase activity (POD), ascorbate peroxidase activity (APX) and superoxide dismutase (SOD), malondialdehyde (MDA) content. In the pot experiment, the parameters studied have shown that the integrated treatments of ZnO-NPs and BF cause a notable enhancement in relative water content 43%–50% and plant biomass. Moreover, the same treatment showed a marked upregulation in enzymes activity (APX, SOD, APX, and CAT) which oxidized the cell-damaging ROS, produced in response to As stress. Likewise, the combined treatment showed a maximum reduction in MDA content 46%–57% and electrolyte leakage in As treated plants as compared to stressed plants. On the other hand, total soluble sugar 114%–170% and total protein content 117%–241% escalated. SEM analysis revealed marked damage reduction in the treated cells caused by arsenic toxicity. Thus, the use of BF comprised of rhizobacteria along with ZnO-NPs could be a very effective bio source for improving maize plant growth under As stress. In in silico study, As mediated network of proteins showed positive and negative regulation of As activity that leads to stress generation for housekeeping genome.
Article
Two field experiments were conducted at Farm of Cairo University’s Faculty of Agriculture in Giza to evaluate a new glass fertilizer (GF) composition on pea plants. The compound is created by melting a variety of raw materials to acquire oxides (60% P2O5, 30% K2O, 3.5% ZnO, 3.5% MnO and 3% Fe2O3 wt %). Control treatment was a full dose of recommended chemical fertilizers (100% RDF), Whereas other treatments were GF at a rate of 60 kg fed⁻¹, GF at rate of 30 kg fed⁻¹, 50% RDF, 100% RDF + biofertilizers, GF at rate of 60 kg fed⁻¹ + biofertilizers, GF at rate of 30 kg fed⁻¹ + biofertilizers, 50% RDF + biofertilizers, and untreated treatment (without fertilizers). The results indicate that, the treatment 60 kg fed⁻¹ GF plus biofertilizers induced increasing pea pod yield by 55.6% and 63.23% when compared with the control treatment in the first and second seasons respectively.
Article
The stimulated effects of elevated CO2 concentration decline over time in many C3 plants. However, the phenomenon is a rare occurrence on plants hosting some symbious bacteria. The photosynthesis acclimation associated with an extended period of high CO2 concentration was therefore studied in cherry tomato that treated with a kind of photosynthetic bacteria. Bio-fertilization with photosynthetic bacteria, which can fix nitrogen for host crops and contains a variety of growth promoting factors, can play an important role in maintaining photosynthetic activity. In this research, we conducted a CO2 elevation experiment combined different water regimes and inoculation with photosynthetic bacterium, to evaluate the improvement of photosynthesis acclimation by using photosynthesis bacteria, and to explore associated mechanisms for artificial chamber grown cherry tomatoes. As a result of these experiments, we found that elevated CO2 had a positive effect on cherry tomato photosynthetic activity and yield of all treatment. After 55 days of CO2 injection, photosynthetic acclimation was found in the plant of uninoculated photosynthetic bacteria, which were most pronounced in high water treatments. Reduced irrigation amounts decreased the magnitude of photosynthetic acclimation, but relative fruit yield gradually decreased after achieving a maximum. In contrast, the photosynthetic bacteria inoculated plants just showed a slightly down-regulation of photosynthesis under durative high CO2 condition. Because inoculation of photosynthetic bacteria increased the photosynthetic pigment content, mesophyll conductance, maximum carboxylation rate and maximum electron transport rate. Furthermore, inoculation with the photosynthetic bacteria diminished the yield penalties caused by the reduced irrigation treatment through promoting nitrogen content and relieve starch accumulation in tomato leaves compared to those of the uninoculated control. And enhanced yield of inoculated plants grown under durative high CO2 concentration were observed. The results suggest that photosynthesis bacteria application could be a potential means to further improve the CO2 stimulation effect on cherry tomato production.
Article
Increased food demands and ceasing nutrient deposits have resulted in a great shortfall between the food supply and demand and would be worse in the years to come. Higher inputs of synthetic fertilizers on lands have resulted in environmental pollution, persistent changes in the soil ecology, and physicochemical conditions. This has greatly decreased the natural soil fertility thereby hindering agricultural productivity, human health, and hygiene. Bio-based resilient nutrient sources as wastewater-derived algae are promising as a complete nutrient for agriculture and have the potential to be used in soilless cultivations. Innovations in nano-fortification and nano-sizing of minerals and algae have the potential to facilitate nutrients bioavailability and efficacy for a multifold increase in productivity. In this context, various options on minerals nanofertilizer application in agricultural food production besides efficient biofertilizer have been investigated. Algal biofertilizer with the nanoscale application has huge prospects for further agriculture productivities and fosters suitable development.
Article
Fragaria × ananassa is a widely-consumed fruit worldwide, valued for its pleasant flavor and nutritional properties. However, its lack of fragrance, unlike wild strawberries, results in customer dissatisfaction. In this study, we tested whether the biofertilizer Saccharomyces cerevisiae can enhance the aroma of strawberry. We used different fertilization methods, namely, mycorrhizal fertilization (MF) and foliar fertilization (FF), to investigate the effects of S. cerevisiae on various characteristics of F. ananassa. The results showed that the application of yeast under MF significantly increased the amount of soluble sugars and total volatiles. However, no significant difference was detected in the anthocyanin content. The amount of total volatiles in fruits under different treatments was 18.17 (MF), 11.78 (FF), and 9.51 (control) μg·g⁻¹ fresh weight (FW). The main volatiles obtained from the fruits under MF, FF, and control treatments were esters (51.45%, 44.39%, and 29.39%, respectively), alcohols (35.93%, 28.77%, and 6.58%, respectively), and aldehydes (5.86%, 18.31%, and 62.88%, respectively). The photosynthetic rate and intercellular CO2 concentration were significantly influenced by the utilization of yeast strains. The MF treatment with yeast resulted in higher photosynthetic rate, and the plants from the FF treatment recording the highest intercellular CO2 concentration. Integrating the data of metabolites, it was suggested that S. cerevisiae, by generating CO2, promotes photosynthesis, leading to the increased sugar content in the fruits, which subsequently enhances the content of 3(2H)-Furanone, 4-methoxy-2, 5-dimethyl (DMMF) and phenylalanine-derived volatiles.
Article
The present study aims to assess the effect of Thiobacillus and sulfur on morphological and biochemical properties of medicinal pumpkin properties under deficit irrigation based on a split-plot design. For this purpose, water stress was applied as a main factor in three levels (control, no irrigation in flowering stage, no irrigation in fruiting), and Thiobacillus and sulfur fertilizers as sub-plots (250 kg/ha). The results revealed water stress significantly reduced stem diameter, fruit weight, fruit yield, and 1000-seed weight. In contrast, Thiobacillus + sulfur significantly increased fruit weight, fruit yield, 1000-seed weight, seed yield, and oil content. Furthermore, deficit irrigation and fertilizers influenced fatty acid of medicinal pumpkin. The interaction of fertilizer and deficit irrigation was significant on all seed oil compositions, fruit weight and yield as well as seed weight and yield. The fatty acid profile of the oil showed that it is composed primarily of oleic, linoleic, palmitic, stearic, and linolenic acids. Masoodi, S. and Hakimi, L. 2017. 'Medicinal pumpkin responses to Thiobacillus and sulfur under water stress'.
Article
The present study was carried out to elucidate the effects of organic manures (FYM, vermicompost and forest litter) and biofertilizers (Azotobacter chroococcum and Pseudomonas fluorescens) on plant growth, yield and fruits quality of strawberry (Fragaria ananassa Duch. cv. Chandler) under field conditions. Sixteen treatments (including a control) were used in this study. Among these, treatment T13 (50 % FYM + 50 % Vermicompost + Azotobacter + Pseudomonas) was found most effective to enhance plant growth parameters viz. plant height, plant spread, leaf area per plant, and induced early flowering. Maximum increase in yield per plant and yield per plot were achieved by the application of 50 % FYM + 50 % Vermicompost + Pseudomonas (T12), which was at par of T13. However, fruit quality parameters including ascorbic acid, total sugar, total phenolic content, and antioxidant capacity were found significantly higher in T13. Higher availability of nutrients (Nitrogen, Phosphorus and Potassium) in soil was also recorded in this treatment. Principle component analysis revealed that different treatments (T9 -T13, T15 and T16) showed positive effects on plant growth, yield and fruit quality parameters. Among these, T13 and T15 were found most effective to increase yield and fruit quality parameters. The PCA analysis also revealed that ‘Days to flowering’ was independent and negatively correlated to other planting value parameters. Similarly, total acid content in fruit did affect other fruit quality parameter, including antioxidant capacity. The combination of manures and biofertilizers has shown potential to increase crop yield and its nutritive properties under field conditions. Therefore, we concluded that the combination of biofertilizers with organic manures (especially, FYM and vermicompost) should be used for sustainably higher production of quality strawberries especially under organic farming system. Such approaches have a higher rationale with small farm or hill agriculture system where farmers are generally resource poor and have low input capacity.
Chapter
Biofertilizer is a substance containing live microorganisms which exhibit beneficial properties toward plant growth and development. Various mechanisms are used by microbial strains in order to enhance nutrient uptake, improve soil fertility and increase crop yields such as nitrogen fixation, potassium and phosphorus solubilization, excretion of phytohormones, production of substances suppressing phytopathogens, guarding plants from abiotic and biotic stresses and detoxification of belowground pollutants. Taking into consideration growing consumption requirements on Earth and hazards arising from the excessive use of chemical fertilizers and pesticides, biofertilizers are thought to be a promising and non-toxic alternative to synthetic agro-chemicals, including fungal control and minimization of mycotoxins contamination. The implementation of microbial inoculants is considered to overcome the shortcomings associated with chemical-based farming techniques, therefore research into widespread use of biofertilizers is one of the mainstream in scientific work for the development of sustainable agriculture.
Article
This study aimed to investigate the combined effect of native sulfur-oxidizing bacteria and different sources of sulfur on pH, electrical conductivity, sulfate content in soil, plant growth indices and sulfate uptake by maize under different moisture conditions. A native sulfur-oxidizing bacteria was isolated and identified based on phenotypic characteristics and 16s rDNA sequencing. In this regard, a factorial experiment was conducted in a completely randomized design including Thiobacillus bacteria, sulfur sources, moisture and incubation time as experiment’s factors with three replications. Bacteria in two levels (with and without bacterial isolate), sulfur in three forms (elemental sulfur, granular sulfur and without sulfur), and moisture content in three levels (100%, 75% and 50% of field capacity) were considered. Results obtained from incubation experiment showed that the treatments effect on pH changes, electrical conductivity and the amount of sulfate ion were significant in 1% level and the highest pH changes and sulfur oxidation was related to BS 100% field capacity (inoculated and fertilized with elemental sulfur) treatment in second week. About greenhouse experiment, application of 570 mg sulfur per kg in the form of elemental sulfur and bacterial inoculum significantly increased stem diameter, plant height, shoot weight and sulfate uptake by maize plant. Inoculation of Thiobacillus along with elemental sulfur increases the oxidation of elemental sulfur resulting in increased nutrients availability in soil, consequently increased plant growth.
Article
Aloe vera (Aloe barbadensis Miller) is one of the most important medicinal plants with high resistance to drought, whose tolerability can be promoted using biofertilizers. The purpose of this study was to determine the influence of biofertilizers on some physiological traits and leaf fresh weight of Aloe vera under different irrigation regimes. The experiments were conducted in a research field in Iran (Boushehr with warm and dry climate) during 2016-2018. Irrigation treatments included 25, 50, 75 and 100% of water requirement and the applied biofertilizers treatments were mycorrhizal fungi (MF) (Glomus mosae), phosphate solubilizing bacteria (PSB) (including Pseudomonas putida strain P13 and Pantoea agglomerans strain P5), MF + PSB, and control (without any biofertilizers). The results of three harvests showed advantages of biofertilizers (specially the combination of MF and PSB) utilization on all determined factors such as total chlorophyll and carotenoid contents, leaf proline, and soluble sugar amount. The highest yield was obtained in full irrigation, but due to the absence of significant difference in leaf fresh weight of this treatment with 50% irrigation, as well as the water deficit in Boushehr, located in semi-arid region, 50% irrigation and combination of MF and PSB biofertilizers is recommended. Therefore, Aloe vera is an acceptable option for planting in Boushehr province according to its scant water consumption.
Article
This study was conducted to investigate the role of phenolic compounds in the antioxidant defense system in Malva parviflora L. plants treated with cadmium (Cd). After surface sterilization, the seeds were sown on seedling trays. Forty-day-old plants were then transferred to hydroponic cultures with Cd (40 μM) or without Cd (control). Some biochemical and physiological parameters were assayed on the sixth day after Cd treatment. Based on the results, the plants showed an increase in leaf soluble carbohydrates, total phenolic compounds, total flavonoids, and phenylalanine ammonia-lyase (PAL) activity at the end of the exposure period. However, length, fresh weight, chlorophyll (Chl) b, total Chl, stomatal conductance and starch content decreased under Cd treatment. There was no significant difference between the plants exposed to Cd and the control group for Chl a, SPAD index, carotenoids, and anthocyanins as well as the H2O2 content six days after treatment. The Cd content in the roots was considerably higher than that in the shoots. In assessing the antioxidant capacity of plant extracts, different results were observed using 1, 1-diphenyl-2-picryl-hydrazyl (DPPH) test and beta-carotene/linoleic acid bleaching assay. According to the results of this study, it seems that increased activity of PAL enzyme leads to an increase in biosynthesis of phenolic compounds in M. parviflora. This mechanism probably increases the antioxidant capacity of the plant to suppress Cd-induced toxicity and oxidative stress.
Article
The present study aims to assess the effect of Thiobacillus and sulfur on morphological and biochemical properties of medicinal pumpkin properties under deficit irrigation based on a split-plot design. For this purpose, water stress was applied as a main factor in three levels (control, no irrigation in flowering stage, no irrigation in fruiting), and Thiobacillus and sulfur fertilizers as sub-plots (250 kg/ha). The results revealed water stress significantly reduced stem diameter, fruit weight, fruit yield, and 1000-seed weight. In contrast, Thiobacillus + sulfur significantly increased fruit weight, fruit yield, 1000-seed weight, seed yield, and oil content. Furthermore, deficit irrigation and fertilizers influenced fatty acid of medicinal pumpkin. The interaction of fertilizer and deficit irrigation was significant on all seed oil compositions, fruit weight and yield as well as seed weight and yield. The fatty acid profile of the oil showed that it is composed primarily of oleic, linoleic, palmitic, stearic, and linolenic acids.
Article
Currently, industrial sludge is generated in large amount annually. Industrial sludge is a solid or semi-solid material consisting of all compounds removed from wastewater, as well as any substances added to the biological and chemical operation units during the treatment process. The composition of sludge may vary considerably. Furthermore, distinctive treatment and disposal methods are necessary as sludge produced from different industries would have different characteristics. Therefore, processing and disposing of industrial sludge is a challenging and complex environmental problem. Landfilling, incineration and agricultural land application are the three most commonly employed methods for the disposal of industrial sludge. Among the three methods, the agricultural land application is a convenient and economical disposal alternative for industrial sludge. However, industrial sludge could have high putrescible content and pathogenic hazards. One possible way to ensure that the industrial sludge could be reused on agricultural land is by conditioning and stabilizing the sludge using a pretreatment process. One of the pretreatment processes which could be employed in this context is vermicomposting. Vermicomposting is an alternative for biological stabilization of organic wastes, with the addition of earthworms. Through vermicomposting, industrial sludge could be transformed into matured organic fertilizer or vermicompost in a shorter period. Thus, this paper reviewed the recent literature on utilizing the vermicomposting process to manage industrial sludge in order to assess the feasibility of this technology. The present review would also provide a brief overview of the production and treatment methods of industrial sludge.
Article
Progress of the Dumas and Kjeldahl procedures over the past century is reviewed. Many recent papers claim that various modifications of the standard Kjeldahl method enhance accuracy, precision, or speed, and reduce cost of analysis. Furthermore, several authors advocate use of Pyrex tubes heated in an aluminum block for digestion instead of traditional Kjeldahl flasks. A review of current semimicro-Kjeldahl methodology suggests that proceeding under the following conditions gives satisfactory results: sample size, 50–200 mg for plant material, 100–500 mg for soil; digestion acid, concentrated H2SO4; sample size ratio (mL/g) of 16:1 for soils and 22:1 for plant materials; digestion salt, minimum 0.33 g K2SO4 added/mL H2SO4; catalysts, add CuSO4 5H2O at rate of 10% (w/w) of K2SO4 added, HgO at 5% (w/w) of K2SO4, or add Se to K2SO4–CuSO4 5H2O mixtures at rate of 1% (w/w) K2SO4; digestion time, 1 and 3 h past clearing for plant materials and soils, respectively; pretreatments, use salicylic acid or reduced iron to recover nitrate from sample. Use of Pyrex tubes heated in an aluminum block appears suitable for digestions. Our results indicate that the 2 commercial tube digestion systems tested produce satisfactory recovery of total N from soils and plant materials. Ammonium in Kjeldahl digests may be quantitatively determined by distillationtitration, ammonia electrode, or colorimetric techniques.
Article
In this research, elemental sulfur was applied at eight rates with and without Thiobacillus inoculation in calcareous soils which had 23%, 17% and 8.5% Total Neutralizing Value(TNV). The highest grain yield, biological yield, plant height, and concentrations of iron (Fe) and zinc (Zn) in shoot were obtained with application of S⁰ at rates which neutralized 2% and 4% of soil TNV, while highest available nutrients and plant-phosphorus (P) were recorded with application of S⁰ at rates which neutralized 16% and 20% of soil TNV. Maximum indices were recorded in soil which had 17% TNV, so that available P, Fe and zinc (Zn) increased by 167.33%, 35.67% and 81.70% compared with control respectively with application of 9.14 g S° g⁻¹ soil. Thiobacillus inoculation increased all of indices (except Fe concentration) compared with non-inoculated control. The results reveal that sulfur application along with Thiobacillus can increase nutrients availability, nutrients uptake and yield of wheat grown in calcareous soils.
Article
Most plant nutrients are optimally available when soil pH is close to neutral. In this experiment the effects of Thiobacillus and Mycorrhiza on nutrient uptake and grain yield of maize were studied on an alkaline soil as factorial experiment based on randomized complete blocks design. Treatments consisted of mycorrhizal fungi (M): inoculated (m1) and non-inoculated (m0), thiobacillus(T): inoculated(t1) and non-inoculated(t0) and sulfur(S) (S0, S1:250 and S2:500 kg.ha−1). Inoculation of Mycorrhiza, Thiobacillus, and sulfur application decreased soil pH and increased grain yield and seed oil content. The lowest soil pH and the highest sulfur content obtained from combination of thiobacillus and 500 kg.ha−1 sulfur. Inoculation of thiobacillus and S application significantly decreased root colonization. The highest Fe content was in combination of mycorrhizal inoculation and 500 kg.ha−1 sulfur. Grain P content significantly increased by mycorrhizal inoculation and S application. The highest grain yield obtained from combination of thiobacillus with 500 kg.ha−1 sulfur.
Article
Chemoautotrophic (Thiobacillus ferrooxidans) and heterotrophic sulphur-oxidizing bacteria (M2 and A12) were used along with pyrite amendment (FeS2) to canola (Brassica campestris var toria) cv Bhavani and wheat (Triticum aestivum) cv HD 2285 crops grown in sulphur-deficient alkaline soil. Results showed that the grain and straw yields and nitrogen uptake of canola and wheat were significantly increased by bacterization. Besides nitrogen, uptake of other nutrients (Fe and Mn) was also increased by these microorganisms. In general, pyrite amendment along with bacterization improved yields and nutrient uptake in canola and wheat over other treatments without pyrite addition.
Article
Photosynthesis is one of the most important biological processes in biosphere, which provides production of organic substances from atmospheric CO2 and water at expense of solar energy. In this review, we contemplate computer models of oxygenic photosynthesis in the context of feedback regulation of photosynthetic electron transport in chloroplasts, the energy-transducing organelles of plant cell. We start with a brief overview of electron and proton transport processes in chloroplasts coupled to ATP synthesis and consider basic regulatory mechanisms of oxygenic photosynthesis. General approaches to computer simulation of photosynthetic processes are considered, including the random walk models of plastoquinone diffusion in thylakoid membranes and deterministic approach to modeling electron transport in chloroplasts based on the mass action law. Then we focus on a kinetic model of oxygenic photosynthesis that includes key stages of the linear electron transport, alternative pathways of electron transfer around photosystem I (PSI), transmembrane proton transport and ATP synthesis in chloroplasts. This model includes different regulatory processes: pH-dependent control of the intersystem electron transport, down-regulation of photosystem II (PSII) activity (non-photochemical quenching), the light-induced activation of the Bassham-Benson-Calvin (BBC) cycle. The model correctly describes pH-dependent feedback control of electron transport in chloroplasts and adequately reproduces a variety of experimental data on induction events observed under different experimental conditions in intact chloroplasts (variations of CO2 and O2 concentrations in atmosphere), including a complex kinetics of P700 (primary electron donor in PSI) photooxidation, CO2 consumption in the BBC cycle, and photorespiration. Finally, we describe diffusion-controlled photosynthetic processes in chloroplasts within the framework of the model that takes into account complex architecture of chloroplasts and lateral heterogeneity of lamellar system of thylakoids. The lateral profiles of pH in the thylakoid lumen and in the narrow gap between grana thylakoids have been calculated under different metabolic conditions. Analyzing topological aspects of diffusion-controlled stages of electron and proton transport in chloroplasts, we conclude that along with the NPQ mechanism of attenuation of PSII activity and deceleration of PQH2 oxidation by the cytochrome b6f complex, the intersystem electron transport may be down-regulated due to light-induced alkalization of the narrow partition between adjacent thylakoids of grana. The computer models of electron and proton transport described in this article may be integrated as appropriate modules into a comprehensive model of oxygenic photosynthesis.
Article
Chlorophyll fluorescence is a non-invasive measurement of photosystem II (PSII) activity and is a commonly used technique in plant physiology. The sensitivity of PSII activity to abiotic and biotic factors has made this a key technique not only for understanding the photosynthetic mechanisms but also as a broader indicator of how plants respond to environmental change. This, along with low cost and ease of collecting data, has resulted in the appearance of a large array of instrument types for measurement and calculated parameters which can be bewildering for the new user. Moreover, its accessibility can lead to misuse and misinterpretation when the underlying photosynthetic processes are not fully appreciated. This review is timely because it sits at a point of renewed interest in chlorophyll fluorescence where fast measurements of photosynthetic performance are now required for crop improvement purposes. Here we help the researcher make choices in terms of protocols using the equipment and expertise available, especially for field measurements. We start with a basic overview of the principles of fluorescence analysis and provide advice on best practice for taking pulse amplitude-modulated measurements. We also discuss a number of emerging techniques for contemporary crop and ecology research, where we see continual development and application of analytical techniques to meet the new challenges that have arisen in recent years. We end the review by briefly discussing the emerging area of monitoring fluorescence, chlorophyll fluorescence imaging, field phenotyping, and remote sensing of crops for yield and biomass enhancement.
Article
Iron chlorosis is widespread in corn, sorghum and soybeans growing in calcareous soils in Iran. A field experiment was conducted to investigate the effect of S treatments on yield and uptake of Fe, Mn and Zn by corn, sorghum and soybeans. Elemental S (powder sulfur) was incorporated into the soil before planting with the rates of zero, 100, 200 and 400 kg/ha. Results showed that elemental S decreased the soil pH and HCC3 concentration of soil extract, and increased soil DTPA‐ extractable Fe, Mn and Zn. Iron, and Zn uptake increased while Mn uptake decreased significantly by corn, sorghum and soybeans for almost all the treatments and Iron chlorosis was corrected. Yield increase over control was significant for sorghum and soybeans for all and every treatment. For corn, however yield showed signigicant increase over control only for 200 and 400 kg elemental S/ha. The results indicated that elemental S treatment was an effective means to alleviate iron chlorosis as well as to increase yield for corn, sorghum and soybeans in calcareous soils.
Article
1. Stark verarmte Suspensionen vonChlorella pyrenoidosa wurden im Licht und im Dunkeln, bei An- und Abwesenheit von Kohlendioxyd, mit Glucose und organischen Suren gefttert und die Zunahme der Zellpolysaccharide nach der Anthronmethode bestimmt. Mit Glucose, pfelsure, sowie Citronensure als Substraten bersteigt die Polysaccharidsynthese im Licht (+CO2) die Summe der im Licht mit CO2 (photosynthetische CO2-Assimilation) und im Dunkeln mit Substrat (oxydative Assimilation) erzielten Syntheseleistungen. Der Effekt wird als Folge einer zustzlichen Energieaufnahme und lichtabhngigen Phosphorylierung gedeutet. 2. Die Messung des Brenztraubensureverbrauchs unter vier verschiedenen Versuchsbedingungen ( Licht, CO2) zeigte, da die Sure im Licht rascher umgesetzt wird als im Dunkeln. Durch CO2-Entziehung im Licht wird der Umsatz noch erhht. Sureeinbau und photosynthetische CO2-Fixierung konkurrieren anscheinend um die verfgbare Energie. 3. Zur Erfassung des Gaswechsels beim Umsatz organischer Substrate durch Grnalgen im Licht wird eine manometrische Methode angegeben. Whrend des Acetatumsatzes im Licht nimmt der Assimilationsquotient (O2/–CO2) Werte an (>1), die auf eine berwiegende Fettsuresynthese hinweisen.
Article
Simple sugars, oligosaccharides, polysaccharides, and their derivatives, including the methyl ethers with free or potentially free reducing groups, give an orange-yellow color when treated with phenol and concentrated sulfuric acid. The reaction is sensitive and the color is stable. By use of this phenol-sulfuric acid reaction, a method has been developed to determine submicro amounts of sugars and related substances. In conjunction with paper partition chromatography the method is useful for the determination of the composition of polysaccharides and their methyl derivatives.
Article
Chlorophyll captures and redirects light-energy and is thus essential for photosynthetic organisms. The demand for chlorophyll differs throughout the day and night and in response to changing light conditions. Moreover, the chlorophyll biosynthesis pathway is up to certain points shared between the different tetrapyrroles; chlorophyll, heme, siroheme and phytochromobilin, for which the cell has different requirements at different time points. Combined with the phototoxic properties of tetrapyrroles which, if not properly protected, can lead to formation of reactive oxygen species (ROS), the need for a strict regulation of the chlorophyll biosynthetic pathway is obvious. Here we describe the current knowledge on regulation of chlorophyll biosynthesis in plants by the chloroplast redox state with emphasis on the Mg-chelatase situated at the branch point between the heme and the chlorophyll pathway. We discuss the proposed role of the Mg-chelatase as a key regulator of the tetrapyrrole pathway by its effect on enzymes both up- and downstream in the pathway and we specifically describe how redox state might regulate the Mg-branch. Finally, we propose that a recently identified NADPH-dependent thioredoxin reductase (NTRC) could be involved in redox regulation or protection of chlorophyll biosynthetic enzymes and describe the possible modes of action by this enzyme.
Article
A greenhouse experiment was carried out with the objective of evaluating the effects of the elementary sulphur inoculated with Thiobacillus, compared with gypsum, in the amendment of a alluvial sodic saline soil from the Brazilian semiarid region, irrigated with saline water and grown with the tropical legumes leucena and mimosa. The treatments consisted of levels of sulphur (0; 300 and 600 kg/ha) and gypsum (1,200 and 2,400 kg/ha), irrigation using different waters containing the salts NaHCO3, MgCl2, CaCl2, NaCl and KCl, with different electrical conductivities (ECs: 0.2. 6.1 and 8.2 dS/m at 25 degrees C). Based on the results it appears that saline water increased exchangeable Na+, K+, Ca2+, Mg2+, and soil pH. Sulphur inoculated with Thiobacillus was more efficient than gypsum in the reduction of the exchangeable sodium of the soil and promoting leaching of salts, especially sodium. Sulphur inoculated with Thiobacillus reduced the EC of the soil saturation extract to levels below that adopted in soil classification of sodic or saline sodic. Leucena was more tolerant to salinity and mimosa more resistant to acidity promoted by sulphur inoculated with Thiobacillus.