Effect of Flood Stress on Soybean Seed Germination in the Field

Flooding is an abiotic stress that impacts soybean [Glycine max (L.) Merr.] growth and reduces seed germination. Effect of flooding on soybean plant grown at different growth stage has been previously conducted and reported. However, soybean seed germination responses to flood stress are largely unknown. The objective of this study was to elucidate flooding influence on soybean seed germination after planting in the field. The research showed that seed germination rate (SGR) of each genotype, without flood stress, was significantly different and ranged between 64.7% to 84.0% and 69.0% to 90.7% while using untreated and fungicide-treated seed (P < 0.0001), respectively. Results indicated that fungicide treatment improved soybean seed survival and germination in the field. The average of SGR of high-yielding soybean group was significantly higher than those of non-high-yielding soybean (P < 0.0001). The results indicated that high-yielding trait of each genotype was correlated with seed germination and survival. Under flood stress in the field, SGR means of untreated and fungicide-treated seed significantly decreased over eight flooding treatment times (P Flooding effect on germination between untreated and fungicide-treated seed was not significantly different (P = 0.1559). Furthermore, comparing the high-yielding and flood-tolerant soybean groups showed no difference in their SGR means over eight flooding treatment times (P = 0.7687 and P = 0.8490), indicating that soybean seed germination did not depend on genotype, yield, and flood tolerance trait, and seed treated by fungicide did not increase its germination in the field under the flood stress. Hence, it is necessary to develop new soybean seed pelleting to improve seed germination in the field under flooding conditions.

Effect of Water Stress Caused by PEG 6000 on Germination and Seedling Growth of Four Soybean Cultivars

Soybean [Glycine max （L.）] is one of the most important protein and oil seed crop. In attention to time consuming and effect of uncontrolled agents like soil elements and hemisphere, study of tolerance in soybean to water stress during germination was investigated. Four soybean cultivars ＇Williams, Linford, L 17 and M7＇ were screened for drought tolerance by treatment of PEG6000 concentration for induce osmotic potentials （0, -3, -6, -9 bar）. A factorial experiment based on completely randomized design with three replications was conducted. Germination percentage, radicle and hypocotyls length, fresh and dry weight of radicle, hypocotyl and seedling, TWC%, MDG, rate of daily germination and percentage of abnormal seedling were measured. Variance analysis of data indicated that difference between osmotic potential had significant effect on all parameters except germination percentage. A significant reduction in fresh weight of radicle and seedling, percentage of abnormal seedlings was observed for the genotypes as the concentration of PEG increased. In interaction between cultivars and water stress level, Linford and M7 with less damage had the highest yield in fresh and dry weight of radicle, respectively. Drought is one of the most important abiotic limited potential in germination and primary growth on these cultivars.

Pectin methylesterase inhibitors GhPMEI53 and AtPMEI19 improve seed germination by modulating cell wall plasticity in cotton and Arabidopsis

The germination process of seeds is influenced by the interplay between two opposing factors,pectin methylesterase(PME)and pectin methylesterase inhibitor(PMEI),which collectively regulate patterns of pectin methylesterification.Despite the recognized importance of pectin methylesterification in seed germination,the specific mechanisms that govern this process remain unclear.In this study,we demonstrated that the overexpression of GhPMEI53is associated with a decrease in PME activity and an increase in pectin methylesterification.This leads to seed cell wall softening,which positively regulates cotton seed germination.AtPMEI19,the homologue in Arabidopsis thaliana,plays a similar role in seed germination to GhPMEI53,indicating a conserved function and mechanism of PMEI in seed germination regulation.Further studies revealed that GhPMEI53 and AtPMEI19 directly contribute to promoting radicle protrusion and seed germination by inducing cell wall softening and reducing mechanical strength.Additionally,the pathways of abscicic acid(ABA)and gibberellin(GA)in the transgenic materials showed significant changes,suggesting that GhPMEI53/AtPMEI19-mediated pectin methylesterification serves as a regulatory signal for the related phytohormones involved in seed germination.In summary,GhPMEI53 and its homologs alter the mechanical properties of cell walls,which influence the mechanical resistance of the endosperm or testa.Moreover,they impact cellular phytohormone pathways(e.g.,ABA and GA)to regulate seed germination.These findings enhance our understanding of pectin methylesterification in cellular morphological dynamics and signaling transduction,and contribute to a more comprehensive understanding of the PME/PMEI gene superfamily in plants.

Influences of Temperature Regime on Germination of Seed of Wild Soybean(Glycine soja)

As an important plant species with high protein contents,wild soybean(Glycine soja),has drawn much attention and appeared to be useful for the genetic improvement of soybean germplasms.Since temperature is one of the numerous environmental factors affecting the germination of most plants,an experimental study was carried out to determine the effect of temperature on germination of wild soybean(G.soja)seeds.Germination test was conducted by setting up thirty-six constant and alternating temperature regimes,ranging from 5 to 40 ℃(16 h night/8 h day).Responses in germination rate to these temperature regimes were then used to construct a quadratic response surface,giving estimated germination rates with confidence intervals at P ≤ 0.05.The results showed that germination capacity was significantly greater while exposed to constant temperatures of 25 ℃,and under the alternating temperature regime the optimum temperature occurred at the 20/25,25/25,25/30 ℃ regime(16 h/8 h)with the amplitude widened from 0 to 5 ℃.Together with regional monthly climate data,these results could be used to improve and promote the cultivation of wild soybean(G.soja),making it available to develop the location-specific optimum seeding time and to apply weed-control treatments.

Effect of Mucuna Defatted Bran Extracted with Supercritical CO2 on Soybean Seed Germination

In the present work, we investigated the effect of Mucuna deeringiana defatted bran on seed germination of soybean （Glycine max L. Merrill）. For this, the defatted bran was obtained from different operational conditions using CO2 under pressurized conditions as solvent. Oil extractions were carried out in a laboratorial scale unit at temperatures ranging from 310 to 330 K, pressure from 15 to 25 MPa and solvent flow set in 3 mL min^-1. The experiment was conducted in a germination chamber （25℃, 12：12 h light：dark photoperiod）, and the germination rate and germination speed index （GSI） were evaluated for seven days. The results showed that the oil extraction with supercritical CO2 concentrates the allelochemical L-3,4-dihydroxyphenylalanine （L-DOPA） in bran with levels from 1.86% to 4.65%. Subsequent experiments revealed that the rate of soybean seed germination was not affected by defatted bran whereas the GSI increased significantly after treatment. In brief, we concluded that the extraction process with supercritical CO2 is efficient to obtain L-DOPA of Mucuna, which influences the soybean seed germination.

GmSTF accumulation mediated by DELLA protein GmRGAs contributes to coordinating light and gibberellin signaling to reduce plant height in soybean

Plant height influences plant architecture,lodging resistance,and yield performance.It is modulated by gibberellic acid(GA)metabolism and signaling.DELLA proteins,acting as central repressors of GA signaling,integrate various environmental and hormonal signals to regulate plant growth and development in Arabidopsis.We examined the role of two DELLA proteins,GmRGAa and GmRGAb,in soybean plant height control.Knockout of these proteins led to longer internodes and increased plant height,primarily by increasing cell elongation.GmRGAs functioned under different light conditions,including red,blue,and far-red light,to repress plant height.Interaction studies revealed that GmRGAs interacted with the blue light receptor GmCRY1b.Consistent with this,GmCRY1b partially regulated plant height via GmRGAs.Additionally,DELLA proteins were found to stabilize the protein GmSTF1/2,a key positive regulator of photomorphogenesis.This stabilization led to increased transcription of GmGA2ox-7b and subsequent reduction in plant height.This study enhances our understanding of DELLA-mediated plant height control,offering Gmrgaab mutants for soybean structure and yield optimization.

Identification and fine mapping of qSW2 for leaf slow wilting in soybean

Drought is one of the abiotic stresses limiting the production of soybean(Glycine max).Elucidation of the genetic and molecular basis of the slow-wilting(SW)trait of this crop offers the prospect of its genetic improvement.A panel of 188 accessions and a set of recombinant inbred lines produced from a cross between cultivars Liaodou 14 and Liaodou 21 were used to identify quantitative-trait loci(QTL)associated with SW.Plants were genotyped by Specific-locus amplified fragment sequencing and seedling leaf wilting was assessed under three water-stress treatments.A genome-wide association study identified 26 SW-associated single-nucleotide polymorphisms(SNPs),including three located in a 248-kb linkage-disequilibrium(LD)block on chromosome 2.Linkage mapping revealed a major-effect QTL,qSW2,associated with all three treatments and adjacent to the LD block.Fine mapping in a BC_(2)F_(3) population derived from a backcross between Liaodou 21 and R26 confined qSW2 to a 60-kb interval.Gene expression and sequence variation analysis identified the gene Glyma.02 g218100,encoding an auxin transcription factor,as a candidate gene for qSW2.Our results will contribute significantly to improving drought-resistant soybean cultivars by providing genetic information and resources.

Evaluation of Salt Tolerance in Nine Shandong Soybean Cultivars at the Germination Stage

[Objectives] Salt stress is an important abiotic stress affecting soybean yield. This study aimed to screen salt-tolerant soybean varieties to improve the utilization efficiency of saline-alkali land. [Methods]Under three concentrations of salt stress（ 5,10 and 15 g/L）,salt tolerance of nine Shandong soybean cultivars was identified at the germination stage. The number of germinated seeds,relative germination rate,plant height,radicle length and number of fibrous roots were recorded to analyze the relative salt damage index and evaluate the salt tolerance of different soybean cultivars. [Results]With the increase of salt concentration,the number of germinated seeds,plant height and number of fibrous roots showed a decreasing trend with significant differences among different soybean cultivars. Under three concentrations of salt stress,Shengdou 10,Lindou 10 and Hedou 28 exhibit relatively strong salt tolerance,indicating that these cultivars are relatively salt-tolerant and highly salt-tolerant cultivars; Hedou 12,Gaofeng 1,Weidou 9 and Qihuang 34 are moderately salt-tolerant cultivars; Qihuang 30 and Qihuang 31 are relatively sensitive to salt solution under 15 g/L NaC l stress. [Conclusions] This study provided high-quality germplasm materials for the improvement of salt tolerance of soybean varieties.

Emulsifying property,antioxidant activity,and bitterness of soybean protein isolate hydrolysate obtained by Corolase PP under high hydrostatic pressure

Enzymatic hydrolysis of proteins can enhance their emulsifying properties and antioxidant activities.However,the problem related to the hydrolysis of proteins was the generation of the bitter taste.Recently,high hydrostatic pressure(HHP)treatment has attracted much interest and has been used in several studies on protein modification.Hence,the study aimed to investigate the effects of enzymatic hydrolysis by Corolase PP under different pressure treatments(0.1,100,200,and 300 MPa for 1-5 h at 50℃)on the emulsifying property,antioxidant activity,and bitterness of soybean protein isolate hydrolysate(SPIH).As observed,the hydrolysate obtained at 200 MPa for 4 h had the highest emulsifying activity index(47.49 m^(2)/g)and emulsifying stability index(92.98%),and it had higher antioxidant activities(44.77%DPPH free radical scavenging activity,31.12%superoxide anion radical scavenging activity,and 61.50%copper ion chelating activity).At the same time,the enhancement of emulsion stability was related to the increase of zeta potential and the decrease of mean particle size.In addition,the hydrolysate obtained at 200 MPa for 4 h had a lower bitterness value and showed better palatability.This study has a broad application prospect in developing food ingredients and healthy foods.

Genetic overlap between salt and low-temperature tolerance loci at germination stage of soybean

Salt and low temperature were both very important factors for soybean production. It was necessary to improve the salt stress and low-temperature tolerance of soybean. The main purpose of this paper was to map the quantitative trait loci(QTL) related with salt tolerance and low- temperature tolerance at germination stage with backcross introgression lines(BILs),and analyze the genetic overlap between them. There were 22 QTL located with BC2 F4 introgression populations after salt stress,and 15 QTL were mapped after low-temperature stress. Seven overlapping QTLs between salt tolerance and low-temperature tolerance were detected on 6 linkage groups at germination stage. In total,there were 31.81 % of salt tolerance and low-temperature tolerance loci existed genetic overlap.

Screening and identification of salt tolerance soybean varieties and germplasms

Soil salinization is a globally prevalent abiotic environmental stress.The imbalance of ions caused by high concentrations of sodium chloride results in a 40%reduction in soybean yield.Soybean,as an important crop for soil quality improvement,necessitates the identification of salt-tolerant varieties and germplasms to effectively utilize and enhance saline-alkali land.In this study,we assessed the salt tolerance of 435 soybean varieties and germplasms during the seedling stage.Among them,Qihuang34,You2104,Hongzhudou,Pamanheidou,and Osage exhibited grade 1 salt tolerance rates surpassing other tested materials.Furthermore,Hongzhudou and Qihuang34 demonstrated higher salt tolerance during germination and emergence stages based on their elevated rates of emergence,salt tolerance index,chlorophyll content,and shoot fresh weights.Overall findings provide valuable resources for molecular breeding efforts aimed at developing salt-tolerant soybean varieties suitable for cultivation in saline-alkali soils.

CRISPR/CasRx-mediated resistance to Soybean mosaic virus in soybean

Soybean mosaic virus(SMV),an RNA virus,is the most common and destructive pathogenic virus in soybean fields.The newly developed CRISPR/Cas immune system has provided a novel strategy for improving plant resistance to viruses;hence,this study aimed to engineer SMV resistance in soybean using this system.Specifically,multiple sgRNAs were designed to target positive-and/or negative-sense strands of the SMV HC-Pro gene.Subsequently,the corresponding CRISPR/CasRx vectors were constructed and transformed into soybeans.After inoculation with SMV,39.02%,35.77%,and 18.70%of T_(1)plants were confirmed to be highly resistant(HR),resistant(R),and mildly resistant(MR)to SMV,respectively,whereas only 6.50%were identified as susceptible(S).Additionally,qRT-PCR and DAS-ELISA showed that,both at 15 and 30 d post-inoculation(dpi),SMV accumulation significantly decreased or was even undetectable in HR and R plants,followed by MR and S plants.Additionally,the expression level of the CasRx gene varied in almost all T_(1)plants with different resistance level,both at 15 and 30 dpi.Furthermore,when SMV resistance was evaluated in the T_(2)generation,the results were similar to those recorded for the T_(1)generation.These findings provide new insights into the application of the CRISPR/CasRx system for soybean improvement and offer a promising alternative strategy for breeding for resistance to biotic stress that will contribute to the development of SMV-immune soybean germplasm to accelerate progress towards greater soybean crop productivity.

Assessing the Efficacy of Wheat-Soybean Based Intercropping System at Different Plant Densities in Bambili, Cameroon

Wheat is one of the most important cereals in the world, serving as a staple for millions globally. In the wake of the geopolitical crisis between Russia and Ukraine, it has become incumbent for many countries to invest in wheat production. Improving cropping systems for wheat production is paramount. Intercropping cereals with legumes has tremendous advantages. Therefore, this study was designed to optimize wheat production by intercropping it with soybean at different densities. Between March and August 2023, a randomized complete block design trial was conducted in Bambili, North West of Cameroon with treatments T1 (wheat monocrop at 200,000 plants ha−1), T2 (soybean monocrop at 250,000 plants ha−1), T3 (200,000 wheat and 125,000 soybean ha−1), T4 (100,000 wheat and 250,000 soybean ha−1), T5 (200,000 wheat and 250,000 soybean ha−1) and T6 (100,000 wheat and 125,000 soybean ha−1). Results revealed that growth parameters of wheat were not significantly influenced by monocrop or intercrop. The yield of wheat was significantly higher in the monocrop than the intercrop treatments, with slight variation amongst the intercrop treatments. Soybean yield was higher in the monocrop than in the intercrop, with no variations amongst the intercrop treatments. Only the land equivalence ratio (LER) for T5 was greater than 1.0. The competitive ratio for T5 was 0.54 for wheat and 1.90 for soybean, comparatively lower than the other monocrop treatments. Intercropping wheat and soybean at 200,000:250,000 ratio is recommended.

Identification of Rhizobia Isolated from Nodules of Mexican Commercial Soybean Varieties

Rhizobia, crucial for nitrogen fixation in leguminous plants, play a vital role in soybean cultivation. This study, conducted in Mexico, a major soybean importer, aimed to identify bacteria from nodules of five soybean varieties in high-production regions. Multilocus sequence analysis (MLSA) was employed for enhanced species resolution. The study identified six Bradyrhizobium species: Bradyrhizobium japonicum USDA 110, Bradyrhizobium japonicum USDA 6, Bradyrhizobium elkanii USDA 76, Bradyrhizobium neotropicale, Bradyrhizobium lablabi, and Bradyrhizobium icense. Bradyrhizobium japonicum USDA 110 predominated in the soils, displaying symbiotic preference for the Huasteca 400 variety. However, phylogenetic analysis didn't reveal a clear association between strains, soil, and soybean variety. This research sheds light on the diversity of rhizobia in Mexican soybean cultivation, contributing to the understanding of symbiotic relationships in soybean production systems.

Mapping and identification of QTLs for seed fatty acids in soybean(Glycine max L.)

Soybean is one of the most important sources of vegetable oil.The oil content and fatty acid ratio have attracted significant attention due to their impacts on the shelf-life of soybean oil products and consumer health.In this study,a high-density genetic map derived from Guizao 1 and Brazil 13 was used to analyze the quantitative trait loci of palmitic acid(PA),stearic acid(SA),oleic acid(OA),linoleic acid(LA),linolenic acid(LNA),and oil content(OC).A total of 54 stable QTLs were detected in the genetic map linkage analysis,which shared six bin intervals.Among them,the bin interval on chromosome 13(bin106-bin118 and bin123-bin125)was found to include stable QTLs in multiple environments that were linked to OA,LA,and LNA.Eight differentially expressed genes(DEGs)within these QTL intervals were determined as candidate genes according to the combination of parental resequencing,bioinformatics and RNA sequencing data.All these results are conducive to breeding soybean with the ideal fatty acid ratio for food,and provide the genetic basis for mining genes related to the fatty acid and oil content traits in soybean.

A comparative study on the role of conventional,chemical,and nanopriming for better salt tolerance during seed germination of direct seeding rice

Salinity is one of the most significant risks to crop production and food security as it harms plant physiology and biochemistry.The salt stress during the rice emergence stages severely hampers the seed germination and seedling growth of direct-seeded rice.Recently,nanoparticles(NPs)have been reported to be effectively involved in many plant physiological processes,particularly under abiotic stresses.To our knowledge,no comparative studies have been performed to study the efficiency of conventional,chemical,and seed nanopriming for better plant stress tolerance.Therefore,we conducted growth chamber and field experiments with different salinity levels(0,1.5,and 3‰),two rice varieties(CY1000 and LLY506),and different priming techniques such as hydropriming,chemical priming(ascorbic acid,salicylic acid,and γ-aminobutyric acid),and nanopriming(zinc oxide nanoparticles).Salt stress inhibited rice seed germination,germination index,vigor index,and seedling growth.Also,salt stress increased the over accumulation of reactive oxygen species(H_(2)O_(2) and O_(2)^(-)·)and malondialdehyde(MDA)contents.Furthermore,salt-stressed seedlings accumulated higher sodium(Na^(+))ions and significantly lower potassium(K^(+))ions.Moreover,the findings of our study demonstrated that,among the different priming techniques,seed nanopriming with zinc oxide nanoparticles(NanoZnO)significantly contributed to rice salt tolerance.ZnO nanopriming improved rice seed germination and seedling growth in the pot and field experiments under salt stress.The possible mechanism behind ZnO nanopriming improved rice salt tolerance included higher contents of α-amylase,soluble sugar,and soluble protein and higher activities of antioxidant enzymes to sustain better seed germination and seedling growth.Moreover,another mechanism of ZnO nanopriming induced rice salt tolerance was associated with better maintenance of(K^(+))ions content.Our research concluded that NanoZnO could promote plant salt tolerance and be adopted as a practical nanopriming technique,promoting global crop production in saltaffected agricultural lands.

J-family genes redundantly regulate flowering time and increase yield in soybean

Soybean(Glycine max)is a short-day crop whose flowering time is regulated by photoperiod.The longjuvenile trait extends its vegetative phase and increases yield under short-day conditions.Natural variation in J,the major locus controlling this trait,modulates flowering time.We report that the three J-family genes influence soybean flowering time,with the triple mutant Guangzhou Mammoth-2 flowering late under short days by inhibiting transcription of E1-family genes.J-family genes offer promising allelic combinations for breeding.

Soybean maize strip intercropping:A solution for maintaining food security in China

The practice of intercropping leguminous and gramineous crops is used for promoting sustainable agriculture,optimizing resource utilization,enhancing biodiversity,and reducing reliance on petroleum products.However,promoting conventional intercropping strategies in modern agriculture can prove challenging.The innovative technology of soybean maize strip intercropping(SMSI)has been proposed as a solution.This system has produced remarkable results in improving domestic soybean and maize production for both food security and sustainable agriculture.In this article,we provide an overview of SMSI and explain how it differs from traditional intercropping.We also discuss the core principles that foster higher yields and the prospects for its future development.

Drought-triggered repression of miR166 promotes drought tolerance in soybean

Drought stress limits agricultural productivity worldwide.Identifying and characterizing genetic components of drought stress-tolerance networks may improve crop resistance to drought stress.We show that the regulatory module formed by miR166 and its target gene,ATHB14-LIKE,functions in the regulation of drought tolerance in soybean(Glycine max).Drought stress represses the accumulation of miR166,leading to upregulation of its target genes.Optimal knockdown of miR166 in the stable transgenic line GmSTTM166 conferred drought tolerance without affecting yield.Expression of ABA signaling pathway genes was regulated by the miR166-mediated regulatory pathway,and ATHB14-LIKE directly activates some of these genes.There is a feedback regulation between ATHB14-LIKE and MIR166 genes,and ATHB14-LIKE inhibits MIR166 expression.These findings reveal that drought-triggered regulation of the miR166-mediated regulatory pathway increases plants drought resistance,providing new insights into drought stress regulatory network in soybean.

Arginine promotes seed energy metabolism,increasing wheat seed germination at low temperature

Low temperatures during germination inhibit seed growth,lead to small and weak seedlings,and significantly reduce the wheat yield.Alleviating the adverse effects of low temperature on wheat seed germination is highly important for achieving high and stable wheat yields.In this study,Tongmai 6(insensitive)and Zhengmai 113(sensitive),which have different low-temperature sensitivities during germination were treated with low temperature during germination.The transcriptome,metabolome and physiological data revealed that low temperature decreased the germination rate,downregulated the expression of a large number of genes involved in regulating glycometabolism,and inhibited carbon,nitrogen(especially amino acids)and energy metabolism in the seeds.Arginine content increased at low temperature,and its increase in the low-temperature-tolerant variety was significantly greater than that in the sensitive variety.Arginine priming experiment showed that treatment with an appropriate concentration of arginine improved the seed germination rate.The conversion of starch to soluble sugar significantly increased under exogenous arginine conditions,the content of key metabolites in energy metabolism increased,and the utilization of ATP in the seeds increased.Taken together,arginine priming increased seed germination at low temperature by relieving inhibition of seed carbon and nitrogen metabolism and improving seed energy metabolism.