Pod Stage Research Articles

Effects of mixed plantings of field pea in conjunction with spring triticale harvested at different growth stages on total nitrogen and exogenous amino acids concentrations in green fodder

ABSTRACT As sustainable agriculture is developing more and more rapidly, the effects of various populations of soil microorganisms on plant growth and development, including symbiosis, is gaining importance. The aim of the work was to determine the impact of component share in the mixture and harvest date on total nitrogen uptake and exogenous amino acid concentration in field pea/spring triticale mixtures grown for green fodder. Two factors were examined in an experiment: factor I – component share in the mixture: field pea (FP) 100%, spring triticale (ST) 100%, FP 75%+ST 25%, FP 50%+ST 50%, FP 25%+ST 75%; factor II – harvest date: field pea flowering stage, field pea flat green pod stage. The highest content of leucine (15.00 g·kg−1 d.m.), valine (6.31 g·kg−1 d.m.), methionine (4.32 g·kg−1 d.m.), histidine (4.15 g·kg−1 d.m.) in the examined mixtures was found in the field pea/spring triticale mixture containing 75 + 25% of the respective components and harvested at the field pea flowering stage. The highest tryptophan content in the examined mixtures was revealed in mixtures of field pea and spring triticale with 75% + 25% (1.89 g·kg−1 d.m.) and 50 + 50% (1.78 g·kg−1 d.m.) components harvested at the field pea flowering stage.

Physiological insights on soybean response to drought

As most of the soybean in Europe is grown in rainfed conditions, climate aberrations are causing significant crop yield variability. To stabilise the yield and shift the sources of supply to European-grown soybean, stable and adaptable cultivars must be created by breeding. To better understand the mechanism of drought tolerance in specific germplasm, more knowledge needs to be acquired by research. Therefore, this research aimed to examine the physiological insights on soybean response to drought exposed plants (50% available water holding capacity) by monitoring the relative water content (RWC), lipid peroxidation (TBARS), pigments (Chl a and b), proteins and photosynthetic efficiency during five days in the pod stage. The decrease of RWC in both tested genotypes due to the drought effect, coupled with TBARS increase, indicates lipid peroxidation, which resulted in photosynthetic pigment and protein changes. Most of the chlorophyll a fluorescence parameters suggested plants initiated a defence mechanism to water deficiency, i.e. there was an initial adjustment on the first and second day of drought exposed plants, followed by drastic changes in electron flow in photosystem II (PSII). According to the correlation analysis, the effect of drought was prevalent for Chl b, Chl a/b, relative variable fluorescence at 30 ms (VI), the density of reaction centres (RC/CS0), absorption, trapping, electron transport and dissipation flux per reaction centre (ABS/RC, TR0/RC, ET0/RC and DI0/RC), plastoquinone at quinone A binding niche reducing RCs per PSII antenna chlorophylls (RC/ABS) and performance index (PIABS), meaning these parameters are good indicators of drought stress, that can facilitate the selection of genotypes and increase the efficiency of breeding programmes. Among tested materials, Korana had lower sensitivity to drought and smaller reduction of yield components than OS-211, indicating a better response of its defence mechanism to oxidative stress caused by lack of water. The methods tested and confirmed in this research could be used for screening large numbers of genotypes to determine in the soybean breeding programs aiming to select superior genotypes adaptable to weather changes.

Changes in carbohydrate content in mixtures of field pea and spring triticale determining the quality of green fodder

Green fodder obtained from mixtures of legume and cereals can be of good quality for direct feeding. Obtaining good quality fodder from mixtures cultivated on arable land is possible on the condition of proper share of components, harvest time and plant selection. The aim of this study was to evaluate the effect of the share of components in the mixture of pea with spring triticale and the harvest date on carbohydrates content in green matter. A field experiment was conducted from 2016 to 2018 and two factors were studied: I. Share of components in the mixture: field pea - clean sowing, spring triticale - clean sowing, field pea 75% + spring triticale 25%, field pea 50% + spring triticale 50%, field pea 25% + spring triticale 75%. II. Harvest date: flowering stage of field pea, flat green pod stage of field pea. The highest content of total carbohydrates and water soluble carbohydrates, among the mixtures, was found in the mixture with 75% share of pea and 25% share of spring triticale. The harvest date had no effect on the concentration of total carbohydrates, while delaying the harvest date caused a decrease in the water soluble carbohydrates content in the green matter of the mixtures.

First Report of Fusarium oxysporum f. sp. ciceris on Chickpea (Cicer arietinum) in Serbia

Chickpea (Cicer arietinum L.) is one of the most commonly consumed legume crops worldwide, cultivated in more than 55 countries (FAOSTAT, 2017). However, in Serbia, it is a novel crop grown on approximately 120 acres, but the areas under this crop slightly increase each year. Fusarium wilt caused by F. oxysporum f. sp. ciceris is one of the most economically important disease in the most chickpea-growing areas (Jimenez-Diaz et al., 2015), but yet there has been no formal report of the Fusarium wilt of chickpea in Serbia. In June 2018, the first symptoms of Fusarium wilt were registered at Rimski Šančevi (Vojvodina Province), Serbia (N 45019.311' E 019049.933') as wilted chickpea plants grouped in patches on approximately 5% plants in the area of 3 acres. Symptoms as yellowing and necrosis of foliage appeared as late wilt in the podding stage. Roots of affected plants showed no external discoloration, but cross-sections showed dark-brown discoloration of xylem tissue. To isolate the causal agent, symptomatic plants were collected, and ten cuttings of symptomatic root tissue were surface disinfected with 2% sodium hypochlorite solution for 5 min, rinsed three times in sterile distilled water, air-dried on sterilized filter paper and plated on potato dextrose agar (PDA) and water agar (WA) amended with streptomycin sulfate. After seven days of incubation at 25°C in the dark, isolates were preliminarily identified according to their morphological characters and Fusarium Laboratory Manual (Leslie and Summerell, 2006). For each isolate 100, micro/macroconidia and chlamydospores were measured. Conidia were hyaline; macroconidia sickle-shaped, with blunt ends, 2-4 septa (10.1-17.7 x 3.1-5.8 µm); microconidia ellipsoidal, 0-1 septa (4.9-8.6-2.7-3.5 µm). Chlamydospores were globose (4.3-8.8 µm). Representative isolates (K343, K375 and K378) were purified by a single-spore technique for further analyses (Leslie and Summerell, 2006). Molecular identification of three representative isolates (K343, K375 and K378) was made by sequencing the rRNA internal transcribed spacer (ITS) region and translation elongation factor 1α (TEF1) gen. For all isolates, the ITS and TEF1 genes were amplified and sequenced with primers ITS1/4 (White et al. 1990), EF1-728 and EF1-986 (Rehner and Buckley 2005). Based on a BLAST search of the NCBI nucleotide database, the ITS sequences (GenBank MK920204.1, MK928423.1 and MK928424.1) had 99.8% identity with F. oxysporum f. sp. ciceris isolate (MK074845.1). The TEF1 (GenBank MN788462.1, MN788463.1 and MN788464.1) had 96.3 -100% identities with F. oxysporum f. sp. ciceris isolate (FJ538245.1). The pathogenicity test was conducted on 7-day old plants according to the drench method described by Maitlo et al. (2016). The concentration of inoculation suspensions was adjusted on 1x106, and ten plants per isolate were tested and inoculated with 10 ml of suspension. Control plants were drenched with 10 ml of sterilized distilled water. Nine days after inoculation, first symptoms as leaves wilting and white mycelia presence around stem base occurred on plants inoculated with isolate K378. On day 11, the first symptoms occurred on plants inoculated with isolates K343 and K375 as well. Up to the 13th day after inoculation, all plants were wilted, and the pathogen was successfully reisolated and confirmed as F. oxysporum f.sp. ciceris. To the best of our knowledge, this is the first report of F. oxysporum f.sp. ciceris causing Fusarium wilt on chickpea in Serbia. <br> Acknowledgements <br>This research was supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia, grant number: 451-03-9/2021-14/200032 <br>

Effects of close planting densities on assimilate accumulation and yield of soybean with different plant branching types

<p id="C3">To investigate the effects of planting density on leaf area index, dry matter accumulation and distribution, and yield components of different varieties, field experiments were conducted using two soybean varieties with different branching types (Zhongzuo XA12938, a main stem type variety; Zhonghuang 13, a branched type variety) under six planting densities (D1: 13.5×10⁴ plants hm^-2; D2: 18.0×10⁴ plants hm^-2; D3: 22.5×10⁴ plants hm^-2; D4: 27.0×10⁴ plants hm^-2; D5: 31.5×10⁴ plants hm^-2; D6: 36.0×10⁴ plants hm^-2). The results showed that as planting densities increased, soybean LAI reached the highest values (&gt;4) earlier, from 47.0 d and 54.6 d (D1) to 31.0 d and 32.9 d (D6) after seedling emergence for Zhongzuo XA12938 and Zhonghuang 13, respectively. Compared to Zhonghuang 13, the high LAI values in Zhongzuo XA12938 lasted longer and decreased less at the middle and late stages. The degree of increase in dry matter with density varied between treatments. At podding stage, dry weight increased by 77.53% and 51.21% in the high-density treatment (D6) compared to the low-density treatment (D1) for Zhongzuo XA12938 and Zhonghuang 13, respectively. The percentage of dry matter in reproductive organs at maturity stage increased and then decreased with increasing density. The highest yields were achieved under D5 (5000.45 kg hm^-2) treatment and remained stable at increasing densities for Zhongzuo XA12938. The highest yields for both years were achieved under D4 (4477.90 kg hm^-2) and D5 (3935.30 kg hm^-2) treatments for Zhonghuang 13. The average yield of Zhongzuo XA12938 was significantly higher by 22.37% than that of Zhonghuang 13. Grey correlation analysis revealed that plant height and effective pods per unit area were closely related to yield in Zhongzuo XA12938, while effective grains per unit area and height of centre of gravity were more highly correlated with yield in Zhonghuang 13. Zhongzuo XA12938 moderate increase in density can increase the LAI and prolong the duration of its high value, promote dry matter accumulation, increase the proportion of reproductive organs, and improve the yield in soybean. Varieties with strong meristem regulation can be used to improve yields and increase benefits by appropriately increasing planting density in production.

Effects of Neem Aqueous Extract (Azadirachta indica) against Aphids and Aphid-borne Virus in Cowpea (Vigna unguiculata L. Walp)

Pests and diseases are among the major factors limiting plant growth and yields. Pests are known vectors of pathogens including viruses. Proper management of plant pests is an indirect means of controlling viral diseases in plants. This study aimed at comparing the potential of neem extract and a synthetic insecticide (lambda cyhalothrin) for the management of aphids and Cowpea aphid-borne mosaic virus (CABMV) in five different cowpea (Vigna unguiculata) genotypes and to determine the residual effects of the insecticide in the cowpea grains. The experimental field was laid out in randomized complete block design with three replicates. Treatments included; spraying of cowpea plots with aqueous neem extract and lambda cyhalothrin (LC) twice at foliage stage, once at flowering and podding stages. Control plots were left unsprayed. Data were obtained on growth and yields of cowpea genotypes as well as the pest and virus disease traits. Results of the Analysis of Variance (ANOVA) revealed that variations attributable to genotypes were significant (p ≤ 0.01) for cowpea yields and virus disease traits. Treatments applied influenced the occurrence of pests and virus diseases. Neem extract reduced aphid infestations and virus diseases as much as the insecticide. Ife BPC accumulated a very high level of LC (1.14 ppm) in its grain when compared with the maximum residue level (MRL) for lambda cyalothrin in cowpea seeds. The study concludes that the use of eco-friendly bio-pesticide such as neem aqueous extract is effective for the management of aphids and aphid-borne virus in cowpea fields.&#x0D; Keywords: Aphids; aqueous extract; cowpea; neem; pesticide; virus

Physiology and metabonomics reveal differences in drought resistance among soybean varieties

BackgroundThe soybean is an important food crop worldwide. Drought during the first pod stage significantly affects soybean yield, and understanding the metabolomic and physiological changes in soybeans under drought stress is crucial. This study identified the differential metabolites in initial pod stage soybean leaves under polyethylene glycol-simulated drought stress, using ultra performance liquid chromatography and tandem mass spectrometry, and the physiological indexes related to drought resistance.ResultsPhysiologically, drought resistance also generates enzyme and antioxidant activity; levels of superoxide dismutase, peroxidase, and catalase first increased and subsequently decreased, while those of soluble sugar, soluble protein, malondialdehyde, and proline content increased in both varieties. The contents of CAT, proline and soluble sugar in Heinong 44 (HN44) were higher than those in Heinong 65 (HN65), and the contents of MDA were lower than those in HN65. In metabolomics, the OPLS-DA model was used to screen different metabolites. KEGG analysis showed that the two varieties resisted drought through different ways. Amino acid metabolism and lipid metabolism play a key role in drought resistance of the two varieties, respectively. TCA cycle was one of the core pathways of drought resistance in two varieties. Changes in the content of l-Asparagine and citric acid may be one of the reasons for the difference in drought resistance between the two varieties.ConclusionsWe think that the reasons of drought resistance among soybean varieties are as follows: the main metabolic pathways are different under drought stress; the contents of metabolites in these metabolic pathways are different; some physiological indexes are different, such as MDA, CAT, proline content and so on. Our study enhances the understanding of the metabolomic soybean drought stress response and provides a reference for soybean drought resistance breeding.

Effects of Biochar With Inorganic and Organic Fertilizers on Agronomic Traits and Nutrient Absorption of Soybean and Fertility and Microbes in Purple Soil.

Biochar is a kind of organic matter that can be added into the soil as a soil amendment to improve its quality. What are the effects of using biochar on purple soil and soybeans? Can the use of biochar reduce the use of fertilizers? This is our concern. Therefore, we carried out this study. The objectives of our study were to evaluate the effects of biochar, inorganic and organic fertilizer application on plant growth, chlorophyll content, photosynthetic gas exchange, and yield of soybean as well as fertility and microbial community in purple soil, and to appraise the possible reduction rate of inorganic fertilizer under the biochar application. A pot experiment was conducted with three levels of biochar, two levels of inorganic fertilizer, and two levels of organic fertilizer in a randomized complete block. The results indicated that the low rate of biochar together with half rate of inorganic fertilizer and organic fertilizer increased the plant growth of soybean. Meanwhile, the chlorophyll content, root growth, and yield of soybean were increased by 16.61, 197.73, and 96.7%, respectively, with biochar compared with no biochar. The high rate of biochar with half rate of inorganic fertilizer and organic fertilizer can promote the exchange of photosynthetic gas in soybean, and the photosynthetic rate increased by 45.25% compared with the blank control. At the full pod stage, the nitrogen content, phosphorus content, and potassium content of the whole plant under the high rate of biochar were 28.35, 13.65, and 28.78%, respectively, higher than that of the blank control. The application of biochar increased nitrogen, phosphorus, and potassium uptake of soybean. The high rate of biochar with half rate of inorganic fertilizer and organic fertilizer can improve soil nutrient content and soil microbial community. Compared with no biochar treatments, total organic carbon (TOC) increased by 740.28%, and cation exchange capacity (CEC) increased by 54.17%. Phospholipid fatty acid (PLFA) increased by 65.22%, and all kinds of soil microorganisms increased to varying degrees. In conclusion, the application of biochar can reduce the use of organic and inorganic fertilizers, improve the agronomic traits and yield of soybean, and play a positive role in soil nutrients and soil microorganisms.

Peanut and cotton intercropping increases productivity and economic returns through regulating plant nutrient accumulation and soil microbial communities

BackgroundIntercropping (IC) has been widely adopted by farmers for enhancing crop productivity and economic returns; however, the underpinning mechanisms from the perspective of below-ground interspecific interactions are only partly understood especially when intercropping practices under saline soil conditions. By using permeable (100 μm) and impermeable (solid) root barriers in a multi-site field experiment, we aimed to study the impact of root-root interactions on nutrient accumulation, soil microbial communities, crop yield, and economic returns in a peanut/cotton IC system under non-saline, secondary-saline, and coastal saline soil conditions of China.ResultsThe results indicate that IC decreased the peanut pods yield by 14.00, 10.01, and 16.52% while increased the seed cotton yield by 61.99, 66.00, and 58.51%, respectively in three experimental positions, and consequently enhanced the economic returns by compared with monoculture of peanut (MP) and cotton (MC). The higher accumulations of nutrients such as nitrogen (N), phosphorus (P), and potassium (K) were also observed in IC not only in the soil but also in vegetative tissues and reproductive organs of peanut. Bacterial community structure analysis under normal growth conditions reveals that IC dramatically altered the soil bacterial abundance composition in both peanut and cotton strips of the top soil whereas the bacterial diversity was barely affected compared with MP and MC. At blossom-needling stage, the metabolic functional features of the bacterial communities such as fatty acid biosynthesis, lipoic acid metabolism, peptidoglycan biosynthesis, and biosynthesis of ansamycins were significantly enriched in MP compared with other treatments. Conversely, these metabolic functional features were dramatically depleted in MP while significantly enriched in IC at podding stage. Permeable root barrier treatments (NC-P and NC-C) counteracted the benefits of IC and the side effects were more pronounced in impermeable treatments (SC-P and SC-C).ConclusionPeanut/cotton intercropping increases crop yield as well as economic returns under non-saline, secondary-saline, and coastal saline soil conditions probably by modulating the soil bacterial abundance composition and accelerating plant nutrients accumulation.

Transcriptomic analysis of Vigna radiata in response to chilling stress and uniconazole application

BackgroundChilling injury of mung bean (Vigna radiata (L.)) during the blooming and podding stages is a major agricultural threat in Northeast China. Uniconazole (UNZ) can alleviate water deficit stress in soybean and waterlogging stress in mung bean. However, there has been no report on the effect of UNZ application on the growth and transcriptomic profile of mung bean under chilling stress.ResultsUNZ application before chilling stress at the R1 stage alleviated the decline in mung bean yield. UNZ delayed the decrease in leaf chlorophyll content under chilling stress at the R1 stage and accelerated the increase in leaf chlorophyll content during the recovery period. Eighteen separate RNA-Seq libraries were generated from RNA samples collected from leaves exposed to six different treatment schemes. The numbers of DEGs specific for UNZ treatment between D1 + S vs. D1 and D4 + S vs. D4 were 708 and 810, respectively. GO annotations showed that photosynthesis genes were obviously enriched among the genes affected by chilling stress and UNZ application. KEGG pathway enrichment analysis indicated that 4 pathways (cutin, suberin and wax biosynthesis; photosynthesis; porphyrin and chlorophyll metabolism; and ribosome) were downregulated, while plant–pathogen interaction was upregulated, by chilling stress. UNZ application effectively prevented the further downregulation of the gene expression of members of these 4 KEGG pathways under chilling stress.ConclusionsUNZ application effectively delayed the decrease in photosynthetic pigment content under chilling stress and accelerated the increase in photosynthetic pigment content during the recovery period, thus effectively limiting the decline in mung bean yield. UNZ application effectively prevented the further downregulation of the gene expression of members of 4 KEGG pathways under chilling stress and increased mung bean tolerance to chilling stress.

Response of carbon, nitrogen and phosphorus concentration and stoichiometry of plants and soils during a soybean growth season to O3 stress and straw return in Northeast China

Carbon (C), nitrogen (N) and phosphorus (P) concentrations and stoichiometry play important roles in biogeochemical cycles of the ecosystems, yet it is still unclear how the allocations of C, N and P concentrations and stoichiometry among plant organs and soils related to O3 stress and straw return. Here, a pot experiment was conducted in open top chambers to monitor the response of C, N and P concentrations and stoichiometry of leaves, stems, roots and soils during a growing season (branching, flowering and podding stages) of soybean (Glycine max; a species highly sensitive to O3) to background O3 concentration (44.8 ± 5.6 ppb), O3 stress (79.7 ± 5.4 ppb) and straw treatment (no straw return and straw return). O3 stress significantly decreased root biomass. Straw return significantly increased root biomass under O3 stress at branching and flowering stages. Generally, O3 stress and straw return showed significant effects on the C, N and P concentrations of leaves and soils, and stoichiometric ratios of leaves, stems and microbial biomass. The C, N and P concentrations and stoichiometry of leaves, stems, roots and soils in response to O3 stress and straw return at the branching stage were inconsistent with the changes observed at the flowering and podding stages. The P conversion efficiency showed significant relationship with root P concentration under the combined effects of O3 stress and straw return. Altogether, the present study indicated that C, N and P concentrations of soybean might be more important than stoichiometric ratios as a driver of root defence against O3 stress in the case of straw return.

Effect of Lambda-Cyhalothrin and Dimethoate on the Growth Response of Cowpea Plants and the Surrounding Soil

Abstract Insecticides are used widely to control insect pests affecting cowpea and their residues are often deposited in the soil. This may impact the physico-chemical characteristics of the soil and the plant health. This study was designed to investigate the growth response of cowpea treated with lambda-cyhalothrin and dimethoate and the insecticides influence on the physico-chemical characteristics of the soil. Three cowpea seeds were planted per polyethylene bag containing top soil, and later thinned to two plants. The insecticides were assayed singly or combined. The insecticides were applied at the pre-flowering (30th day), flowering (50th day) and at podding (70th day) stages of cowpea growth. The physico-chemical parameters of treated soils were assayed. Treated soils with lambdacyhalothrin and dimethoate and the control were slightly acidic with pH varying from 5.78 to 6.55. Soil organic matter and soil nutrients such as nitrogen, phosphorous, potassium and sodium had lowest values in untreated soil; they had highest values in soil treated with combined insecticides. Lambda-cyhalothrin and dimethoate treatments elicited diverse response from the cowpea plant. Generally, there were slight increase in the vegetative parameters, yield and pod dimensions of treated plants when compared with the control. These insecticides also increased the root nodules, root length and dry weight of cowpea at different concentrations. The combination of these insecticides had positive effect on cowpea without adverse influence on the yield and as well as the soil physicochemical properties.

Identification of the Important Genes of Bradyrhizobium diazoefficiens 113-2 Involved in Soybean Nodule Development and Senescence.

Legume nodule development and senescence directly affect nitrogen fixation efficiency and involve a programmed series of molecular events. These molecular events are carried out synchronously by legumes and rhizobia. The characteristics and molecular mechanisms of nitrogen fixation at soybean important developmental stages play critical roles in soybean cultivation and fertilizer application. Although the gene expression of soybean were analyzed in nodules at five important soybean developmental stages, information on the expression of rhizobial genes in these nodule samples is limited. In the present study, we investigated the expression of Bradyrhizobium diazoefficiens 113-2 genes in the nodule samples from five developmental stages of soybean (Branching stage, flowering stage, fruiting stage, pod stage and harvest stage). Similar gene expression patterns of B. diazoefficiens 113-2 were existed during optimal symbiotic functioning, while different expression patterns were found among early nodule development, nitrogen fixation progress and nodule senescence. Besides, we identified 164 important different expression genes (DEGs) associated with nodule development and senescence. These DEGs included those encoding nod, nif, fix proteins and T3SS secretion system-related proteins, as well as proteins involved in nitrogen metabolism, ABC transporters and two-component system pathways. Gene Ontology, KEGG pathway and homology analysis of the identified DEGs revealed that most of these DEGs are uncharacterized genes associated with nodule development and senescence, and they are not core genes among the rhizobia genomes. Our results provide new clues for the understanding of the genetic determinants of soil rhizobia in nodule development and senescence, and supply theoretical basis for the creation of high efficiency soybean cultivation technology.

Modelling the effects of cold temperature during the reproductive stage on the yield of chickpea (Cicer arietinum L.)

During the reproductive stage, chilling temperatures and frost reduce the yield of chickpea and limit its adaptation. The adverse effects of chilling temperature and frost in terms of the threshold temperatures, impact of cold duration, and genotype-by-environment-by-management interactions are not well quantified. Crop growth models that predict flowering time and yield under diverse climates can identify combinations of cultivars and sowing time to reduce frost risk in target environments. The Agricultural Production Systems Simulator (APSIM-chickpea) model uses daily temperatures to model basic crop growth but does not include penalties for either frost damage or cold temperatures during flowering and podding stages. Regression analysis overcame this limitation of the model for chickpea crops grown at 95 locations in Australia using 70 years of historic data incorporating three cultivars and three sowing times (early, mid, and late). We modified model parameters to include the effect of soil water on thermal time calculations, which significantly improved the prediction of flowering time. Simulated data, and data from field experiments grown in Australia (2013 to 2019), showed robust predictions for flowering time (n = 29; R2 = 0.97), and grain yield (n = 22; R2 = 0.63–0.70). In addition, we identified threshold cold temperatures that significantly affected predicted yield, and combinations of locations, variety, and sowing time where the overlap between peak cold temperatures and peak flowering was minimal. Our results showed that frost and/or cold temperature–induced yield losses are a major limitation in some unexpected Australian locations, e.g., inland, subtropical latitudes in Queensland. Intermediate sowing maximise yield, as it avoids cold temperature, late heat, and drought stresses potentially limiting yield in early and late sowing respectively.

Biological Management of Powdery Mildew of Pea (Pisum Sativum L)

Pea (Pisum sativum) is leguminous crop generally cultivated around globe. Pisum sativum is main pulse crop belonged to the family Leguminoceae rich in nutritional value. In Pakistan Pea crop is cultivated on large area mostly in Punjab and in other provinces. The production of Pea in Pakistan is not so good due to the attack of fungal diseases like Powdery mildew, Anthracnose, Rust and Downy mildew. The Powdery mildew caused by Erysiphe pisi which is bio trophic obligate parasite. Different environmental factors play significant role in occurrence of that disease. When plants are on pod stages it shows epidemic form. It effects whole green surface of pea initially symptoms are lesion formation and powder like whitish spots on upper and lower surface of leaves. When the pathogen proliferates in all aerial parts; plant became dead. Infected plant seed produced unpleasant smell which decreases the quality of peas. The intensity of the disease was reduced by increase resistance in host plant by some plant extracts ie. Neem Extract, Garlic Extract. Pathogenicity of Erysiphe pisi was supressed by the application of some bio agents ie. Trichoderma harzianum and Beauveria bassiana. These applications were served as enviro-safe management and helps to reduce disease severity and increase in numbers and weight of pod/plant which were helping to increase in a yield. From these all treatment most, effective treatment was Garlic Extract which overcome the effect of disease 77% and then Neem Extract 64%. There was also effective result of Trichoderma harzianum and Beauveria bassiana overcome the effect of powdery mildew of pea disease was 51% and 38%. The data onto environmental condition was collected which shows with increase in temperature helps to increase the intensity of disease. Decrease in humidity and solar radiation also helps to increase the disease incidence level. Decrease in wind speed and rain fall also increase the disease intensity.&#x0D;

Biological Management of Powdery Mildew of Pea (Pisum Sativum L)

Pea (Pisum sativum) is leguminous crop generally cultivated around globe. Pisum sativum is main pulse crop belonged to the family Leguminoceae rich in nutritional value. In Pakistan Pea crop is cultivated on large area mostly in Punjab and in other provinces. The production of Pea in Pakistan is not so good due to the attack of fungal diseases like Powdery mildew, Anthracnose, Rust and Downy mildew. The Powdery mildew caused by Erysiphe pisi which is bio trophic obligate parasite. Different environmental factors play significant role in occurrence of that disease. When plants are on pod stages it shows epidemic form. It effects whole green surface of pea initially symptoms are lesion formation and powder like whitish spots on upper and lower surface of leaves. When the pathogen proliferates in all aerial parts; plant became dead. Infected plant seed produced unpleasant smell which decreases the quality of peas. The intensity of the disease was reduced by increase resistance in host plant by some plant extracts ie. Neem Extract, Garlic Extract. Pathogenicity of Erysiphe pisi was supressed by the application of some bio agents ie. Trichoderma harzianum and Beauveria bassiana. These applications were served as enviro-safe management and helps to reduce disease severity and increase in numbers and weight of pod/plant which were helping to increase in a yield. From these all treatment most, effective treatment was Garlic Extract which overcome the effect of disease 77% and then Neem Extract 64%. There was also effective result of Trichoderma harzianum and Beauveria bassiana overcome the effect of powdery mildew of pea disease was 51% and 38%. The data onto environmental condition was collected which shows with increase in temperature helps to increase the intensity of disease. Decrease in humidity and solar radiation also helps to increase the disease incidence level. Decrease in wind speed and rain fall also increase the disease intensity.&#x0D;

​Efficacy of Biopesticides against Pod Bug, Clavigralla gibbosa Spinola (Heteroptera; Coreidae) in Pigeonpea

Background: Pigeonpea is the major pulse crop of India. In reproductive stage pigeonpea is exposed to biotic pests causing damage to flowers, pods and grains. Pod bugs, Clavigralla gibbosa Spinola are one of the major biotic constraints in reducing productivity of pigeonpea. Nymphs and adults suck the sap from pods and cause loss of seed yield. Chemical residues will remain in the grains affecting health of the consumer. Eco-friendly molecules are best alternatives to manage pod bugs. Methods: Efficacy test of biopesticides viz., Lecanicillium lecanii, Beauveria bassiana, Metarhizium anisopliae, NSKE 5%, Neemazol 1% and Sasyarakshak against C. gibbosa was conducted in pigeonpea during Kharif 2017-18 and 2018-19 at Agricultural Research Station, Kalaburagi, Karnataka, India under field conditions with seven treatments including control in three replications. Two sprays were taken at tender pod stage and population was recorded. Pod damage and grain damage was assessed at harvest. Result: NSKE 5% was superior in reducing pod bug population, pod damage and grain damage followed by L. lecanii and neemazol 1%. M. anisopliae was found to be ineffective in reducing the population, pod damage and grain damage. The average grain yield of 1229.10 kg/ha was highest in NSKE 5% followed by L. lecanii (1223.48 kg/ha) and neemazol 1% (1199.53 kg/ha). The B:C was 2.45 in NSKE 5% and 2.43 in L. lecanii were higher than other treatments. Therefore, these two biopesticides can be used for effective management of pod bug in pigeonpea.

Occurrence and Distribution of Dry Root Rot of Chickpea Caused by Macrophomina phaseolina (Tassi) Goid. in Arid Region of Rajasthan

Background: Dry root rot of chickpea caused by Macrophomina phaseolina (Tassi) Goid. is emerging as a serious threat to the chickpea production worldwide. The disease is gaining importance under the changing scenario of climate particularly in the rainfed ecologies of India and in arid and semi-arid region of Rajasthan. The current study was aimed to discusses current status of the disease and role of different factors in disease development to help in searching of possible management options for researchers to alleviate the problem. Methods: A roving survey was conducted to record the occurrence and distribution of dry root rot in ten major chickpea growing districts of Rajasthan during Rabi season 2014-15 and 2015-16. In each district, minimum three locations/villages were selected, in each location/village minimum three fields were selected and the incidence of disease was recorded after counting the diseased and healthy plants. Result: Overall range of disease incidence in all the districts vary from 5.75 to 12.51 per cent with an average of 9.15 per cent in Rajasthan. The maximum disease incidence 12.51 per cent was observed in Jaisalmer district while minimum in Ajmer district. The disease was found very common in sandy and sandy loam soil than any other types of soil. The deshi/local varieties were found to be more susceptible to infection of M. phaseolina as compared to improved varieties. Disease incidence was also observed higher in sprinkler system of irrigation as compared to flood method and rainfed conditions. The maximum disease incidence was observed in plants at flowering and podding stages in the months of February and March.

Effects of selenate applied at two growth stages on the nutrient quality of Cardamine violifolia

Cardamine violifolia is an edible selenium (Se) hyperaccumulator that is mainly distributed in Enshi, China. Here, C. violifolia treated with different selenate concentrations (i.e., 0, 1.5, 20, and 80 μmol L − 1) at the rosette and podding stages in a hydroponic experiment was carried out to investigate the effects of Se accumulation on the nutrient quality of this crop. The shoots accumulated high levels of Se at the rosette and podding stages, and the main Se forms at these stages were selenocystine and selenate. The effects of selenate on the chlorophyll, carotenoid, soluble sugar and protein, total free amino acid, and vitamin C contents of C. violifolia differed between the rosette and podding stages. Selenate treatment reduced total flavonoid and increased the total phenolic acid content at the podding stage. Total glucosinolate content decreased after selenate treatment at the rosette stage. Ten volatile compounds were found in C. violifolia shoots and the dominant volatile observed at the two stages was benzyl isothiocyanate. Selenate treatment demonstrated mixed influences on the volatile compounds. For example, at the rosette stage, selenate treatment inhibited the emission of benzyl isothiocyanate and benzyl isocyanate but promoted the generation of 12,15-octadecadiynoic acid methyl ester. Moreover, selenate treatment reduced the emission of isobutyl isothiocyanate at the podding stage of C. violifolia. These results provide us novel insights into the comprehensive effects of Se on the nutrient quality of Se hyperaccumulators.

Physiological and biochemical responses of soybean plants inoculated with Arbuscular mycorrhizal fungi and Bradyrhizobium under drought stress

BackgroundThe present study aims to study the effects of biofertilizers potential of Arbuscular Mycorrhizal Fungi (AMF) and Bradyrhizobium japonicum (B. japonicum) strains on yield and growth of drought stressed soybean (Giza 111) plants at early pod stage (50 days from sowing, R3) and seed development stage (90 days from sowing, R5).ResultsHighest plant biomass, leaf chlorophyll content, nodulation, and grain yield were observed in the unstressed plants as compared with water stressed-plants at R3 and R5 stages. At soil rhizosphere level, AMF and B. japonicum treatments improved bacterial counts and the activities of the enzymes (dehydrogenase and phosphatase) under well-watered and drought stress conditions. Irrespective of the drought effects, AMF and B. japonicum treatments improved the growth and yield of soybean under both drought (restrained irrigation) and adequately-watered conditions as compared with untreated plants. The current study revealed that AMF and B. japonicum improved catalase (CAT) and peroxidase (POD) in the seeds, and a reverse trend was observed in case of malonaldehyde (MDA) and proline under drought stress. The relative expression of the CAT and POD genes was up-regulated by the application of biofertilizers treatments under drought stress condition. Interestingly a reverse trend was observed in the case of the relative expression of the genes involved in the proline metabolism such as P5CS, P5CR, PDH, and P5CDH under the same conditions. The present study suggests that biofertilizers diminished the inhibitory effect of drought stress on cell development and resulted in a shorter time for DNA accumulation and the cycle of cell division. There were notable changes in the activities of enzymes involved in the secondary metabolism and expression levels of GmSPS1, GmSuSy, and GmC-INV in the plants treated with biofertilizers and exposed to the drought stress at both R3 and R5 stages. These changes in the activities of secondary metabolism and their transcriptional levels caused by biofertilizers may contribute to increasing soybean tolerance to drought stress.ConclusionsThe results of this study suggest that application of biofertilizers to soybean plants is a promising approach to alleviate drought stress effects on growth performance of soybean plants. The integrated application of biofertilizers may help to obtain improved resilience of the agro ecosystems to adverse impacts of climate change and help to improve soil fertility and plant growth under drought stress.