Soybean Resistance Research Articles

Application of bulk segregant RNA-Seq (BSR-Seq) and allele-specific primers to study soybean powdery mildew resistance

BackgroundPowdery mildew (PM) is one of the important soybean diseases, and host resistance could practically contribute to soybean PM management. To date, only the Rmd locus on chromosome (Chr) 16 was identified through traditional QTL mapping and GWAS, and it remains unclear if the bulk segregant RNA-Seq (BSR-Seq) methodology is feasible to explore additional PM resistance that might exist in other varieties.ResultsBSR-Seq was applied to contrast genotypes and gene expressions between the resistant bulk (R bulk) and the susceptible bulk (S bulk), as well as the parents. The ∆(SNP-index) and G’ value identified several QTL and significant SNPs/Indels on Chr06, Chr15, and Chr16. Differentially expressed genes (DEGs) located within these QTL were identified using HISAT2 and Kallisto, and allele-specific primers (AS-primers) were designed to validate the accuracy of phenotypic prediction. While the AS-primers on Chr06 or Chr15 cannot distinguish the resistant and susceptible phenotypes, AS-primers on Chr16 exhibited 82% accuracy prediction with an additive effect, similar to the SSR marker Satt431.ConclusionsEvaluation of additional AS-primers in the linkage disequilibrium (LD) block on Chr16 further confirmed the resistant locus, derived from the resistant parental variety ‘Kaohsiung 11’ (‘KS11’), not only overlaps with the Rmd locus with unique up-regulated LRR genes (Glyma.16G213700 and Glyma.16G215100), but also harbors a down-regulated MLO gene (Glyma.16G145600). Accordingly, this study exemplified the feasibility of BSR-Seq in studying biotrophic disease resistance in soybean, and showed the genetic makeup of soybean variety ‘KS11’ comprising the Rmd locus and one MLO gene.

Development of an NLR-ID Toolkit and Identification of Novel Disease-Resistance Genes in Soybean.

The recognition of pathogen effectors through the nucleotide-binding leucine-rich repeat receptor (NLR) family is an important component of plant immunity. In addition to typical domains such as TIR, CC, NBS, and LRR, NLR proteins also contain some atypical integrated domains (IDs), the roles of which are rarely investigated. Here, we carefully screened the soybean (Glycine max) genome and identified the IDs that appeared in the soybean TNL-like proteins. Our results show that multiple IDs (36) are widely present in soybean TNL-like proteins. A total of 27 Gm-TNL-ID genes (soybean TNL-like gene encoding ID) were cloned and their antiviral activity towards the soybean mosaic virus (SMV)/tobacco mosaic virus (TMV) was verified. Two resistance (R) genes, SRA2 (SMV resistance gene contains AAA_22 domain) and SRZ4 (SMV resistance gene contains zf-RVT domain), were identified to possess broad-spectrum resistance characteristics towards six viruses including SMV, TMV, plum pox virus (PPV), cabbage leaf curl virus (CaLCuV), barley stripe mosaic virus (BSMV), and tobacco rattle virus (TRV). The effects of Gm-TNL-IDX (the domain of the Gm-TNL-ID gene after the TN domain) on the antiviral activity of a R protein SRC7TN (we previously reported the TN domain of the soybean broad-spectrum resistance gene SRC7) were validated, and most of Gm-TNL-IDX inhibits antiviral activity mediated by SRC7TN, possibly through intramolecular interactions. Yeast-two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays showed that seven Gm-TNL-IDX interacted with SMV-component proteins. Truncation analysis on a broad-spectrum antiviral protein SRZ4 indicated that SRZ4TIR is sufficient to mediate antiviral activity against SMV. Soybean cDNA library screening on SRZ4 identified 48 interacting proteins. In summary, our results indicate that the integration of IDs in soybean is widespread and frequent. The NLR-ID toolkit we provide is expected to be valuable for elucidating the functions of atypical NLR proteins in the plant immune system and lay the foundation for the development of engineering NLR for plant-disease control in the future.

Effects of Irrigation with Sodium Nitroprusside on Physiological Characteristics of Soybean under Drought Stress

Background: Although it is a key soybean-producing region, northeast China frequently faces drought. Drought severely affects soybean growth, development and even leads to yield reduction. Methods: Sand cultivation method was employed to investigate the changes in malondialdehyde (MDA) content, nitric oxide (NO) content and individual leaf area of drought-tolerant soybean variety Heinong 44 (HN44) and drought-sensitive soybean variety Heinong 65 (HN65) under drought stress during the flowering stage, with different concentrations of sodium nitroprusside (SNP) used for irrigation. Result: The NO and MDA contents of HN44 and HN65 leaves rose in response to drought stress, MDA content in HN44 and HN65 leaves was noticeably elevated, the individual leaf area showed a downward trend. Irrigation with SNP further increased NO accumulation and reduced membrane lipid peroxidation in the leaves, with the best effect observed at a concentration of 1000 μmol·g-1. In practical production, SNP can be used to alleviate membrane lipid peroxidation damage in soybean leaves and improve soybean drought resistance when encountering drought.

Atmospheric deposition of dicamba herbicide can cause injury to sensitive soybean

ABSTRACT The herbicide dicamba has injured millions of hectares of sensitive plant species in the United States since 2017. This injury has coincided with the commercialization of dicamba-resistant soybean [Glycine max (L.) Merr.] and cotton (Gossypium hirsutum L.). We quantified atmospheric deposition and mass flux of dicamba in 12 soybean production regions of Missouri. Dicamba was routinely detected in weekly deposition samples collected during agriculturally-intensive spray periods. Observed concentrations were indicative of both local (<1 km) and long-distance transport (>1 km) of air-borne dicamba. High deposition events (>100 µg m-2) occurred annually in southeast Missouri, and peak dicamba deposited at these sites (12.5-84.0 µg m-2) was sufficient to injure non-dicamba resistant soybean. Adoption rate of dicamba-resistant crops and atmospheric stability explained much of the variance, and it is difficult for a herbicide product label to address these variables. Overall, these results demonstrated that dicamba was commonly deposited from the atmosphere during the growing season and observed concentrations and fluxes were strongly related to the timing and magnitude of rainfall events, and the amount of dicamba usage near collection sites.

Discrepancy of Growth Toxicity of Polystyrene Nanoplastics on Soybean (Glycine max) and Mung Bean (Vigna radiata).

Nanoplastics, as a hot topic of novel contaminants, lack extensive concern in higher plants; especially the potential impact and mechanism of nanoplastics on legume crops remains elusive. In this study, the toxicity of polystyrene nanoplastics (PS-NPs, 200 nm) with diverse doses (control, 10, 50, 100, 200, 500 mg/L) to soybean and mung bean plants grown hydroponically for 7 d was investigated at both the macroscopic and molecular levels. The results demonstrated that the root length of both plants was markedly suppressed to varying degrees. Similarly, mineral elements (Fe, Zn) were notably decreased in soybean roots, consistent with Cu alteration in mung bean. Moreover, PS-NPs considerably elevated malondialdehyde (MDA) levels only in soybean roots. Enzyme activity data indicated mung bean exhibited significant damage only at higher doses of PS-NPs stress than soybean, implying mung bean is more resilient. Transcriptome analysis showed that PS-NPs stimulated the expression of genes associated with the antioxidant system in plant roots. Furthermore, starch and sucrose metabolism might play a key role in coping with PS-NPs to enhance soybean resistance, but the MAPK pathway was enriched in mung bean. Our findings provide valuable perspectives for an in-depth understanding of the performance of plants growing in waters contaminated by nanoplastics.

First Report of Charcoal Rot on Soybean Caused by Macrophomina phaseolina in Manitoba, Canada.

First Report of Charcoal Rot on Soybean Caused by Macrophomina phaseolina in Manitoba, Canada.

Mitogen-activated protein kinases MPK3 and MPK6 phosphorylate receptor-like cytoplasmic kinase CDL1 to regulate soybean basal immunity.

Soybean cyst nematode (SCN; Heterodera glycines Ichinohe), one of the most devastating soybean (Glycine max) pathogens, causes significant yield loss in soybean production. Nematode infection triggers plant defense responses; however, the components involved in the upstream signaling cascade remain largely unknown. In this study, we established that a mitogen-activated protein kinase (MAPK) signaling module, activated by nematode infection or wounding, is crucial for soybeans to establish SCN resistance. GmMPK3 and GmMPK6 directly interact with CDG1-LIKE1 (GmCDL1), a member of the receptor-like cytoplasmic kinase (RLCK) subfamily VII. These kinases phosphorylate GmCDL1 at Thr-372 to prevent its proteasome-mediated degradation. Functional analysis demonstrated that GmCDL1 positively regulates immune responses and promotes SCN resistance in soybeans. GmMPK3-mediated and GmMPK6-mediated phosphorylation of GmCDL1 enhances GmMPK3 and GmMPK6 activation and soybean disease resistance, representing a positive feedback mechanism. Additionally, 2 L-type lectin receptor kinases, GmLecRK02g and GmLecRK08g, associate with GmCDL1 to initiate downstream immune signaling. Notably, our study also unveils the potential involvement of GmLecRKs and GmCDL1 in countering other soybean pathogens beyond nematodes. Taken together, our findings reveal the pivotal role of the GmLecRKs-GmCDL1-MAPK regulatory module in triggering soybean basal immune responses.

The Effects of Genetic Distance and Genetic Diversity on Genomic Prediction Accuracy for Soybean Quantitative Disease Resistance to Phytophthora sojae

Assessing quantitative disease resistance and other complex traits can be time- and space-consuming, limiting the number of lines that can be evaluated in a breeding program. A potential improvement is the application of genomic prediction models, where genotypic data are used to calculate genomic estimated breeding values, referred to as genomic selection. Genomic prediction uses training datasets, where a germplasm panel is phenotyped and genotyped to calculate genomic estimated breeding values in a validation panel of lines based solely on genotypic data. To develop an initial phenotypic dataset, breeders may consider utilizing previously phenotyped lines in a publicly available dataset, such as plant introductions (PIs) from the USDA Soybean collection. A relevant question is, how effective is genomic prediction across diverse training and prediction panels? To answer this, we used previously collected phenotypic data for quantitative disease resistance toward Phytophthora sojae. Diverse germplasm panels were represented by sets of PIs originating from the United States, the Republic of Korea, and worldwide, for a total collection of 1,768 PIs. The accuracy of the prediction model was significantly influenced by population differentiation between panels, as well as genetic and phenotypic diversity. Low prediction accuracy resulted when the panel used to create the prediction model was highly differentiated from the validation panel. However, the addition of a small number of accessions to the training panel that were more closely related to the validation panel resulted in increased accuracy. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

Virus induced gene silencing confirms oligogenic inheritance of brown stem rot resistance in soybean.

Brown Stem Rot (BSR), caused by the soil borne fungal pathogen Phialophora gregata, can reduce soybean yields by as much as 38%. Previous allelism studies identified three Resistant to brown stem Rot genes (Rbs1, Rbs2, and Rbs3), all mapping to large, overlapping regions on soybean chromosome 16. However, recent fine-mapping and genome wide association studies (GWAS) suggest Rbs1, Rbs2, and Rbs3 are alleles of a single Rbs locus. To address this conflict, we characterized the Rbs locus using the Williams82 reference genome (Wm82.a4.v1). We identified 120 Receptor-Like Proteins (RLPs), with hallmarks of disease resistance receptor-like proteins (RLPs), which formed five distinct clusters. We developed virus induced gene silencing (VIGS) constructs to target each of the clusters, hypothesizing that silencing the correct RLP cluster would result in a loss of resistance phenotype. The VIGS constructs were tested against P. gregata resistant genotypes L78-4094 (Rbs1), PI 437833 (Rbs2), or PI 437970 (Rbs3), infected with P. gregata or mock infected. No loss of resistance phenotype was observed. We then developed VIGS constructs targeting two RLP clusters with a single construct. Construct B1a/B2 silenced P. gregata resistance in L78-4094, confirming at least two genes confer Rbs1-mediated resistance to P. gregata. Failure of B1a/B2 to silence resistance in PI 437833 and PI 437970 suggests additional genes confer BSR resistance in these lines. To identify differentially expressed genes (DEGs) responding to silencing, we conducted RNA-seq of leaf, stem and root samples from B1a/B2 and empty vector control plants infected with P. gregata or mock infected. B1a/B2 silencing induced DEGs associated with cell wall biogenesis, lipid oxidation, the unfolded protein response and iron homeostasis and repressed numerous DEGs involved in defense and defense signaling. These findings will improve integration of Rbs resistance into elite germplasm and provide novel insights into fungal disease resistance.

Colonization compatibility with Bacillus altitudinis confers soybean seed rot resistance.

The plant microbiome and plant-associated bacteria are known to support plant health, but there are limited studies on seed and seedling microbiome to reveal how seed-associated bacteria may confer disease resistance. In this study, the application of antibiotics on soybean seedlings indicated that seed-associated bacteria were involved in the seed rot resistance against a soil-borne pathogen Calonectria ilicicola, but this resistance cannot be carried to withstand root rot. Using PacBio 16S rRNA gene full-length sequencing and microbiome analyses, 14 amplicon sequence variants (ASVs) including 2 ASVs matching to Bacillus altitudinis were found to be more abundant in the four most resistant varieties versus the four most susceptible varieties. Culture-dependent isolation obtained two B. altitudinis isolates that both exhibit antagonistic capability against six fungal pathogens. Application of B. altitudinis on the most resistant and susceptible soybean varieties revealed different colonization compatibility, and the seed rot resistance was restored in the five varieties showing higher bacterial colonization. Moreover, quantitative PCR confirmed the persistence of B. altitudinis on apical shoots till 21days post-inoculation (dpi), but 9 dpi on roots of the resistant variety TN5. As for the susceptible variety HC, the persistence of B. altitudinis was only detected before 6 dpi on both shoots and roots. The short-term colonization of B. altitudinis on roots may explain the absence of root rot resistance. Collectively, this study advances the insight of B. altitudinis conferring soybean seed rot resistance and highlights the importance of considering bacterial compatibility with plant varieties and colonization persistence on plant tissues.

Drip irrigation reduces the toxicity of heavy metals to soybean: By moving heavy metals out of the root zone and improving physiological metabolism

Excessive heavy metal content in soil can seriously hinder plant physiological metabolism and growth. This study, with soybean, examined how drip irrigation reduced heavy metal toxicity. The drip irrigation experiments with four irrigation frequencies were conducted by controlling the lower limit of the soil matric potential (D1: −10 kPa; D2: −20 kPa; D3: −30 kPa; D4: −40 kPa). Through comparison with traditional surface irrigation, the effects of drip irrigation on heavy metal distribution, soybean growth status, physiological metabolism and transcriptome under Cd, Pb and Cr(VI) composite pollution were comprehensively analyzed. The results show that (i) The Cd, Pb and Cr(IV) in soil migrated away from the plant under drip irrigation, thereby reducing the inhibition of heavy metal stress on soybean growth at the root, among which D1 had the best improvement effect on soybean growth. (ii) Drip irrigation improved the resistance of soybean to heavy metal stress, and promoted the transport and fixation of free Cd2+, Pb2+ and Cr6+ in cells, thereby reducing the damage of oxidative stress and heavy metal ions to cell structure. (iii) Drip irrigation was conducive to the energy supply and protein stability of cell physiological metabolism, which helped the improvement of soybean physiological activity. Overall, compared with surface irrigation, drip irrigation reduced the toxicity of heavy metals to soybeans by moving heavy metals out of the root zone and enhancing physiological activity. The results of this study can provide a theoretical basis for the application of drip irrigation technology in the prevention and control of heavy metal pollution, and provide a new strategy for the safe production of agriculture.

Overexpression of GmPAL Genes Enhances Soybean Resistance Against Heterodera glycines.

Soybean cyst nematode (Heterodera glycines, soybean cyst nematode [SCN]) disease adversely affects the yield of soybean and leads to billions of dollars in losses every year. To control the disease, it is necessary to study the resistance genes of the plant and their mechanisms. Isoflavonoids are secondary metabolites of the phenylalanine pathway, and they are synthesized in soybean. They are essential in plant response to biotic and abiotic stresses. In this study, we reported that phenylalanine ammonia-lyase (PAL) genes GmPALs involved in isoflavonoid biosynthesis, can positively regulate soybean resistance to SCN. Our previous study demonstrated that the expression of GmPAL genes in the resistant cultivar Huipizhi (HPZ) heidou are strongly induced by SCN. PAL is the rate-limiting enzyme that catalyzes the first step of phenylpropanoid metabolism, and it responds to biotic or abiotic stresses. Here, we demonstrate that the resistance of soybeans against SCN is suppressed by PAL inhibitor l-α-(aminooxy)-β-phenylpropionic acid (L-AOPP) treatment. Overexpression of eight GmPAL genes caused diapause of nematodes in transgenic roots. In a petiole-feeding bioassay, we identified that two isoflavones, daidzein and genistein, could enhance resistance against SCN and suppress nematode development. This study thus reveals GmPAL-mediated resistance against SCN, information that has good application potential. The role of isoflavones in soybean resistance provides new information for the control of SCN. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Comparative and evolutionary analyses of cyclophilins in Cucumis sativus, Phaseolus vulgaris, and Vitis vinifera

Cyclophilins, ubiquitous proteins present in the majority of organisms including bacteria, fungi, higher plants, humans, and so on, are known to play diverse cellular functions. In this study, we have performed genome-wide analyses of cyclophilins from three plant species, Cucumis sativus, Phaseolus vulgaris, and Vitis vinifera. This analysis revealed 21, 26, and 22 cyclophilins in C. sativus, P. vulgaris, and V. vinifera, respectively. The majority of cyclophilins are present in the cytosol and nucleus, while few were observed in mitochondria and vacuole. A total of 15, 19, and 16 single-domain cyclophilins while 6, 7, and 6 multi domain cyclophilins are present in C. sativus, P. vulgaris, and V. vinifera. Furthermore, phylogenetic analysis showed the grouping of cyclophilins in five major clades with relevance to domains and sub cellular localization. Our study also suggests P. vulgaris and V. vinifera have similar intron exon structures. Eight motifs have been conserved in most cyclophilins out of which six amino acids long motif GSQFFI is prominent. In-silico expression studies revealed CucCYP13 is highly expressed in roots (10 folds higher) and is orthologous to previously reported GmCYP1 of G. max. CucCYP13 from C. sativus has been identified as ortholog of GmCYP1 which plays important role in disease resistance in soybean. Additionally, CucCYP2, PhvCYP22, and GsvCYP5 which have high sequence similarity with Arabidopsis CYP 71 (AT3g44600) could play a key role in gene repression, organogenesis, and meristem development. Overall, the present study offers key insight into this important class of immunophilin, and the newly identified cyclophilins in P. vulgaris, C. sativus, and V. vinifera may play important roles in abiotic stresses and key physiological traits.

Soybean aphid management and perception of insecticide resistance by farmers

Abstract In the Midwest United States, soybean aphids can cause significant economic losses in soybean production. The repeated use of insecticides within the same family has led to the development of insecticide resistance in soybean aphids. Implementing integrated pest management (IPM) and insecticide-resistance management (IRM) strategies can help farmers reduce the frequency of insecticide applications and delay the evolution of soybean aphid resistance while reducing production costs, maintaining yields, and protecting the environment. Farmers play a crucial role in implementing such practices; therefore, to understand farmers’ practices for management of soybean aphids and their perceptions of insecticide resistance, a survey of soybean farmers in Minnesota and North Dakota was conducted in 2021. Overall, the reported decision-making sources were similar for both farmers who changed and those who did not change their aphid management due to insecticide resistance; these were crop consultants and agricultural retailers. The threshold used by farmers in both groups to determine whether to use a foliar insecticide was lower than the research-based threshold for soybean aphids, and farmers were aware that this could contribute to insecticide resistance. In addition, farmers who changed soybean aphid management were more concerned than farmers who did not change about insecticide resistance and were implementing good practices such as scouting, using labeled application rates, and rotating insecticide modes of action. The results of this research can inform the refinement of IPM and IRM programs as well as extension education efforts.

Phytochemical profiling of soybean genotypes using GC-MS and UHPLC-DAD/MS.

Soybean is one of the most economically important crops worldwide. However, soybean yield can be substantially decreased by many diseases. Soybean genotypes could have different reactions to pathogen infection. As a first step toward investigating the biochemical basis of soybean resistance and susceptibility to disease, phytochemicals in the seeds of 52 soybean genotypes previously reported to have different reactions to diseases of soybean rust (SBR), Phomopsis seed decay (PSD), and purple seed stain (PSS) were analyzed. Using GC-MS, a total of 46 compounds were tentatively identified which included 11 chemical groups. Among those, the major group was esters, followed by carboxylic acid, ketone, and sugar moieties. Compounds having reported antioxidant, anti-microbial, and anti-inflammatory activities were also identified. UHPLC-DAD/MS analysis indicated that there were five major isoflavone components presented in the samples, including daidzin, glycitin, genistin, malonyldaidzin, and malonylglycitin. Isoflavones have been reported to play an important role in defense from plant pathogens. Although there was variance in the isoflavone content among soybean genotypes, those with the SBR resistance Rpp6 gene (PI 567102B, PI 567104B, PI 567129) consistently exhibited the highest concentrations of daidzin, glycitin, genistin, and malonyldaidzin. The SBR resistant genotype, PI 230970 (Rpp2) had the greatest amount of genistin. The SBR resistant genotype, PI 200456 (Rpp5) resistant genotype uniquely contained glycitein, a compound that was absent in the other 51 genotypes examined. A PSD-resistant genotype PI 424324B had nearly four times the amount of stigmasterol as PI 556625, which was susceptible to SBR, PSD, and PSS in our previous tests. Results of this study provide useful information for further investigation of the biochemical basis of soybean resistance to diseases. The results may also aid in selection of soybean lines for breeding for resistance to soybean rust and other diseases.

GmCBP60b Plays Both Positive and Negative Roles in Plant Immunity.

CBP60b (CALMODULIN-BINDING PROTEIN 60b) is a member of the CBP60 transcription factor family. In Arabidopsis, AtCBP60b not only regulates growth and development but also activates the transcriptions in immune responses. So far, CBP60b has only been studied extensively in the model plant Arabidopsis and rarely in crops. In this study, Bean pod mottle virus (BPMV)-mediated gene silencing (BPMV-VIGS) was used to silence GmCBP60b.1/2 in soybean plants. The silencing of GmCBP60b.1/2 resulted in typical autoimmunity, such as dwarfism and enhanced resistance to both Soybean mosaic virus (SMV) and Pseudomonas syringae pv. glycinea (Psg). To further understand the roles of GmCBP60b in immunity and circumvent the recalcitrance of soybean transformation, we generated transgenic tobacco lines that overexpress GmCBP60b.1. The overexpression of GmCBP60b.1 also resulted in autoimmunity, including spontaneous cell death on the leaves, highly induced expression of PATHOGENESIS-RELATED (PR) genes, significantly elevated accumulation of defense hormone salicylic acid (SA), and significantly enhanced resistance to Pst DC3000 (Pseudomonas syrangae pv. tomato DC3000). The transient coexpression of a luciferase reporter gene driven by the promoter of soybean SYSTEMIC ACQUIRED RESISTANCE DEFICIENT 1 (GmSARD1) (ProGmSARD1::LUC), together with GmCBP60b.1 driven by the 35S promoter, led to the activation of the LUC reporter gene, suggesting that GmCBP60b.1 could bind to the core (A/T)AATT motifs within the promoter region of GmSARD1 and, thus, activate the expression of the LUC reporter. Taken together, our results indicate that GmCBP60b.1/2 play both positive and negative regulatory roles in immune responses. These results also suggest that the function of CBP60b is conserved across plant species.

The Formation of Water Stress Resistant Soybean Varieties From Genotypes Resulted From Genetic Mutation Between the Second Generation Mutant With High Result Potentials

The aim of the study was to obtain second generation mutant lines (M2) from three gene-mutated soybean seeds, namely M2 Anjasmoro, M2 Argomulyo and M2 Dena-1 which are tolerant to drought stress, water saturation stress and high yield potential. The research was carried out in the Maros district, South Sulawesi, July-November 2022, arranged in a split plot design. The main plot is the application of water consisting of three levels, namely selection of drought stress (C1), selection of water saturation stress (C2) and selection of optimum conditions (C3). Subplots are three second generation soybean seeds resulting from gene mutations (M2), namely: M2 Anjasmoro, M2 Argomulyo and M2 Dena-1. The results showed that the best plant agronomic characters for growth and production factors were M2 Anjasmoro for water saturation stress treatment and M2 Argomulyo and M2 Dena-1 for drought stress treatment. The fastest harvesting age was obtained from the combination of drought stress and M2 Argomulyo, namely 79 days and not significantly different from the combination of drought stress and M2 Dena-1, namely 79.34 days, but significantly different from the other treatment combinations. The production obtained from the seeds resulting from the second generation of gene mutations has begun to show a difference between those given the mutation treatment and their parents, where the combination of water saturation stress and M2 Anjasmoro gave the highest production of 3.20 tonnes/ha higher than the production of its parents which only reached 2. .03-2.25 tonnes/ha. Generation M2 Argomulyo seeds were the longest surviving seeds to recovery from drought stress (38 days), in the sense that M2 Argomulyo seeds were more resistant to drought stress than the other two generations of seeds, namely M2 Anjasmoro (36 days) and M2 Dena-1 (37 days). Meanwhile, the resistance to water saturation was shown by M2 Dena-1 generation seeds, namely 40.67 days, followed by M2 Argomulyo 29.67 days and M2 Anjasmoro 27.33 days.

Genome-wide association study (GWAS) reveals key loci associated with rhizoctonia aerial blight resistance in soybean

Rhizoctonia Aerial Blight (RAB) is caused by Rhizoctonia solani is one of the most worldwide devastating diseases in soybean. In present study, a GWAS was conducted for rhizoctonia aerial blight (RAB) resistance by using 269 diverse soybean genotypes for two consecutive year 2020 & 2021. GWAS analysis revealed two most significant SNPs, located very close each other on chromosome 12 (3193687 & 3193885) and 16 (6074131 & 6076330). Some candidate genes such as related to leucine-rich repeats containing (LRRNT; Glyma.16g064200), protein ubiquitination (F-box-like) and amino acid transmembrane transport (Trp_Tyr_perm; Glyma.16g062500 & Glyma.16g062600) were identified near the significant SNP positions. Our findings may be relevant for future studies and provide insights into the genetic basis for RAB resistance in soybean.

Genome-wide association studies on charcoal rot resistance in soybean (Glycine max, L.)

A genome-wide association study (GWAS) was conducted for Charcoal rot resistance by using 267 soybean germplasm lines. GWAS analysis revealed two most significant SNPs at chromosome 3 (S3_8215775 and S3_8309181) for multiple traits associated with adult plant resistance. Candidate genes related to calcium ion signaling, response to nematode infestation, abscisic acid stimulus and defense response to bacteria were identified within the flanking regions of the significant SNP positions. Among all, one most important gene (Glyma.03G057100) involved in jasmonic acid biosynthesis was identified. Two SNPs each on chromosome 8 (S8_22467783 and S8_22467802) and chromosome 9 (S9_2923863 and S9_2935518), associated with seedlingresistance have also been identified.

Genetic enhancement for grain yield and mungbean yellow mosaic India virus (MYMIV) resistance through introgressions from Glycine soja

The current study aimed at development of early maturing, mungbean yellow mosaic India virus (MYMIV) resistant and higher yield soybean genotypes. Through a series of backcrosses (BC4 generation) MYMIV resistance gene has been introgressed from G. soja in to a widely adaptable cultivar JS 335. Introgression lines, viz., YMV1, YMV2, YMV 11 and YMV 16 having MYMIV resistance and higher yield performance over recurrent parent and other check varieties were identified and characterized. GGE biplots analysis revealed YMV 16 as ideal genotype with respect to 100-seed weight and grain yield whereas YMV 11 was promising under sugarcane-soybean intercropping system in spring season. Further, study also reports the development of an extra-early maturing (72 days) genetic stock NRC 252, which can be a potential parent in breeding for early maturing soybean varieties. Inconclusion, alleles from wild type soybean could improve yield and MYMIV resistance in cultivated soybean. The genotypes developed in the present study will help in reducing the damage caused by MYMIV disease and area expansion of the soybean crop through intercropping with sugarcane.