Background:Soybean (Glycine max), is a globally important oilseed crop whose yield and quality are severely constrained by environmental stress. The Sucrose Transporter (SUT) gene family plays a crucial role in sucrose transport, plant growth, and stress adaptation. However, comprehensive identification and functional characterization of SUT family members in soybean remain largely incomplete. Results:In this study, a total of 12 non-redundant GmSUT genes were identified in soybean. The encoded proteins have predicted molecular weights ranging from 11.80 to 65.88 kDa and theoretical isoelectric points (pI) between 5.73 and 9.44. These genes were classified into three subfamilies (SUTI, SUTIIa and SUTIV) by phylogenetic analysis, with SUTI being the largest group. Gene structure and conserved motif analyses showed that motif composition was largely uniform within each subfamily, except for GmSUT4.1, which retained only two motifs. Chromosomal mapping revealed an uneven distribution across seven chromosomes, with Chr16 harboring four SUTI members. Collinearity analysis indicated a closer evolutionary relationship between soybean and Glycine soja than with Arabidopsis thaliana or Medicago truncatula. Cis -regulatory element analysis identified abundant stress- and hormone-responsive motifs (e.g., ABRE, MeJA-responsive elements), with 83% of promoters containing ABA-responsive elements. Moreover, the transcriptional levels of the GmSUT genes were significantly induced under various abiotic stresses (salt, drought, cold and alkaline) and phytohormone treatments (ABA, and MeJA), demonstrating that multiple GmSUT genes play critical roles in soybean stress adaptation. Conclusions:This study provides a comprehensive identification and characterization of the SUT gene family in soybean (Glycine max), revealing 12 GmSUT genes grouped into three subfamilies (SUTI, SUTIIa, SUTIIV). Expression profiling demonstrated that multiple GmSUT members are rapidly upregulated under stress treatment, underscoring their essential functions in sucrose distribution and stress adaptation. These findings offer valuable insights into the regulatory mechanisms of the GmSUT family and suggest candidate genetic targets for enhancing stress tolerance in soybean.

Phytophthora sojae (P. sojae) is a devastating soil-borne oomycete that severely threatens soybean [Glycine max (L.) Merr.] yield and quality. Abscisic acid (ABA) plays critical roles in plant physiology; however, its genetic mechanisms in regulating pathogen resistance remain unclear. Here, we identify ABA as a negative regulator of soybean immunity. The ABA signaling core component Abscisic acid-insensitive 5 (GmABI5) physically interacts with cyclin-dependent kinase 8 (GmCDK8), and they both function as immune suppressors. GmCDK8 stabilizes the GmABI5 protein by partially inhibiting proteasomal degradation, while GmABI5 transcriptionally activates GmCDK8 expression, forming a positive feedback loop that amplifies immune suppression. Furthermore, the GmCDK8-GmABI5 module coregulates overlapping downstream targets to repress pathogen-inducible lignin biosynthesis genes. Our findings highlight the critical roles of GmABI5 and GmCDK8 in P. sojae resistance through interconnection with phytohormone signaling.

Isoflavonoids, which are abundant in soybeans, increase the utility value of soybean products and mediate plant defenses against diverse stresses. In this study, integrated transcriptomic and ultra-performance liquid chromatography (UPLC) analyses revealed that Phytophthora sojae (P. sojae) infection remodels the isoflavonoid biosynthesis pathway. Exogenous isoflavonoid application significantly increased soybean resistance to P. sojae, suppressing lesion expansion by more than 70% and inhibiting both reactive oxygen species accumulation and host cell death. Resistant evaluation of 228 soybean germplasms revealed 48 germplasms resistant to P. sojae isolate JS08-12, 42 germplasms resistant to isolate W210, and 38 elite germplasms exhibiting resistance against both W210 and JS08-12. Compared with that of the susceptible germplasm (1850.24 μg g-1), the resistant soybean germplasm presented 35.35% higher total isoflavonoids (2504.29 μg g-1), with significant increases in six compounds: 6″-O-malonylgenistin (+33.04%), 6″-O-malonyldaidzin (+43.35%), genistin (+43.34%), daidzin (+43.97%), genistein (+5.99%), and 6″-O-acetylgenistin (+5.48%). Importantly, the elite germplasm YZS180, YZS210, YZS073, and YZS052 presented significantly high levels of seed isoflavonoids (> 3500.00 μg g-1) and strong resistance. We further investigated the crosstalk between abscisic acid (ABA) and isoflavonoids. This study identifies isoflavonoids as defense metabolites against P. sojae and provides elite genetic resources for breeding soybeans with integrated disease resistance and nutritional quality.

Soybean (Glycine max) ranks among the most crucial oil crops worldwide. Nevertheless, the regulatory mechanisms underlying oil accumulation in soybean are still largely unknown. Here, our study identified GmNFYA11 as an interacting protein of the lipid regulatory factor GmWRI1a and elucidated its role in soybean lipid metabolism. Functional analyses demonstrated that GmNFYA11 was involved in the regulation of fatty acid and oil biosynthesis in soybean. Compared to the wild type, overexpression of GmNFYA11 in transgenic soybean significantly increases oil and total fatty acid content, with altered fatty acid composition. Notably, GmNFYA11 enhances the transcription of GmOLEO1 by specifically binding to the CCAAT-box within its promoter, and physically interacts with GmWRI1a to amplify its transcriptional activity on target genes. Furthermore, we identified five haplotypes of GmNFYA11, with Hap02 associated with higher seed oil content. The higher prevalence of Hap01 and Hap02 in cultivated varieties than in landraces suggests their selection during breeding for high-oil traits. Collectively, GmNFYA11 plays an important role in modulating soybean oil content. This study provides novel insights into the molecular mechanisms underlying fatty acid synthesis. It also clarifies domestication-associated variation in oil content. We propose a regulatory module comprising GmNFYA11 and GmWRI1a, which may serve as a promising target for the genetic improvement of soybean oil production.

Abiotic stresses severely constrain soybean productivity worldwide. Here we demonstrate that gmeif2b5 (eukaryotic initiation factors) mutants confer dual stress tolerance through coordinated mechanisms. Integrative RNA-Seq and protein interaction analyses revealed that gmeif2b5 mutants increase lignin deposition to increase drought resilience and balanced Na+/K+ homeostasis to enhance salt tolerance; GmeIF2B5 physically interacts with GmPRX4, a plant heme peroxidase; GmPRX4 overexpression increases drought and salt resistance in soybean; GmeIF2B5 plays the predominant role in the GmeIF2B5-GmPRX4 module, and double mutants exhibiting synergistic stress tolerance improvements. Our work uncovers a 'GmeIF2B5-GmPRX4 regulatory axis' that: mobilises lignin-based structural fortification for enhanced drought resistance and orchestrates ionic equilibrium for increased salt tolerance. This study pioneers the role of eIF2B genes in soybean stress adaptation, establishing a multi-tiered regulatory node for precision molecular design of stress-resilient crops.

Phytophthora root and stem rot caused by Phytophthora sojae (P. sojae) is one of the most destructive diseases to affect soybean (Glycine max (L.) Merr) pro duction. GmSRC2 that encodes a C2 domain-containing protein can respond to various stresses, however, the molecular mechanism of GmSRC2 in resistance of soybean to P. sojae is yet to be fully elucidated. In this study, GmSRC2 was found to be significantly up-regulated under P. sojae treatment; GmSRC2-overexpression (OE) transgenic lines and GmSRC2-silencing transient plants were generated via Agrobacterium tumefaciens mediated transformation and virus-induced gene silencing (VIGS) system, respectively. Infected leaves and cotyledons of OE-GmSRC2-1 and OE-GmSRC2-2 lines showed significant decreases in the disease symptoms and P. sojae biomass than those of wild type (WT); the activities of superoxide dismutase (SOD) and peroxidase (POD) confirmed the accumulation of reactive oxygen species (ROS) in overexpressed transgenic lines. Whereas, silencing of GmSRC2 severely increased the disease symptoms and the biomass of P. sojae. Further, we confirmed that GmSRC2 interacted with the effector PsAvh23 of P. sojae, and the C2 domain was crucial for the interaction. Overexpression of GmSRC2 upregulated the ADA2/GCN5 module upon P. sojae. The aforementioned results demonstrated that GmSRC2 played vital roles in regulating soybean resistance to oomycetes.

Soybean (Glycine max L. Merr) production is severely affected by soil salinization as an important crop. The discovery of salt stress-responsive genes is essential for soybean breeding. To our knowledge, cyclophilins (CYPs) play important roles in salt stresses in crops such as rice and cotton, except in soybean. This study cloned GmCYP2 from soybean salt-tolerant cultivar Suxie No. 1 and obtained ten stable transgenic soybean lines overexpressing GmCYP2 by Agrobacterium rhizogenes-mediated transformation. Two of the higher-expressing transgenic lines (OE1 and OE2) were used to compare salt tolerance with the wild type (WT). Under the salt stress, the chlorophyll content, the maximum efficiency of PSII photochemistry (Fv/Fm) and actual photochemical quantum yield [Y(II)] of OE1 and OE2 lines were significantly higher than those of the WT. Meanwhile, the accumulation of malondialdehyde (MDA) in the OE1 and OE2 lines was significantly lower than that in the WT. In addition, the Na+/K+ ratio was also significantly lower than that of the WT in leaves and roots. The results also confirmed that the salt tolerance of GmCYP2-silencing soybean seedlings obtained by virus-induced gene silencing (VIGS) was reduced compared to the control. Subcellular localization showed that GmCYP2 was expressed in the plasma membrane and nucleus of Nicotiana benthamiana. RNA-seq results demonstrated that GmCYP2 is involved in key regulators of the ABA and Ca2+ signaling pathway. Yeast two-hybrid, bimolecular fluorescence complementation (BiFC) and split-luciferase complementation assay demonstrated that GmCYP2 protein interacts with salt-associated halotolerance 3 (HAL3) protein. These results suggest that the GmCYP2-GmHAL3 module enhances salt tolerance of soybean seedlings by maintaining the Na+/K+ ratio and good photosynthetic state and it may be involved in the ABA and Ca2+ signaling pathway.

The TIR (Toll/interleukin-1 receptor) domain has been proposed to play a signalling role in resistance responses mediated by TIR-containing proteins. The functions of some TIR-domain-containing proteins have been defined in some plants; however, there has been no study evaluating TIR-domain-containing proteins in soybean (Glycine max (L.) Merr.). In this study, GmTIR was isolated from soybean, and its functions under stresses were analysed. Analysis of tissue-specific expression patterns showed that GmTIR was strongly expressed in leaves and weakly expressed in the immature green beans. Treatments with Phytophthora sojae, salicylic acid, methyl jasmonate, abscisic acid, copper, salt and drought significantly increased GmTIR expression, and 1-aminocyclopropane-1-carboxylic acid and low temperature caused slight increases. Compared with wild type expression, GmTIR overexpression in Arabidopsis thaliana led to a higher germination rate under both salt and drought stresses, but the root length of transgenic Arabidopsis was greater than of wild type plants only under salt stress. In response to the stresses, accumulation of proline in transgenic plants was also higher. The results suggest that GmTIR could be a positive factor for promoting the survival of plants under biotic and abiotic stresses.

Drought is one of the most important factors affecting plant growth and productivity. The previous results on drought tolerance (DT) genetic system in soybean indicated a complex of genes not only few ones were involved in the trait. This study is featured with a relatively thorough identification of QTL-allele/candidate-gene system using an efficient restricted two-stage multi-locus multi-allele genome-wide association study, on two comprehensive DT indicators, membership index values of relative plant weight (MPW) and height (MPH), instead of a single biological characteristic, in a large sample (564 accessions) of the Chinese cultivated soybean population (CCSP). Based on 24,694 multi-allele markers, 75 and 64 QTL with 261 and 207 alleles (2–12/locus) were detected for MPW and MPH, explaining 54.7% and 47.1% of phenotypic variance, respectively. The detected QTL-alleles were organized into a QTL-allele matrix for each indicator, indicating DT is a super-trait conferred by two (even more) QTL-allele systems of sub-traits. Each CCSP matrix was separated into landrace (LR) and released cultivar (RC) sub-matrices, which showed significant differentiation in QTL-allele constitutions, with 58 LR alleles excluded and 16 new ones emerged in RC. Using the matrices, optimal crosses with great DT transgressive recombinants were predicted. From the detected QTL, 177 candidate genes were annotated and validated with quantitative Real-time PCR, and grouped into nine categories, with ABA and stress responders as the major parts. The key point of the above results is the establishment of relatively full QTL-allele matrices composed of numerous gene functions jointly conferring DT, therefore, demonstrates the complexity of DT genetic system and potential of CCSP in DT breeding.

Brassinosteroids (BRs) are a group of steroid plant hormones regulating normal growth, development, and stress response in plants. However, the mechanisms by which BRs interfere with the resistance of soybean to Phytophthora sojae (P. sojae) remain largely unknown. The present study analyzed the role of BRs in soybean response against P. sojae by comparative proteomic approaches. A total of 52,381 peptides were obtained by trypsin digestion of 9,680 proteins, among which 6,640 proteins were quantified, and 402 proteins were identified as differentially expressed proteins (DEPs). Further analysis revealed that DEPs were significantly involved in the lignin biosynthesis pathway. The expression of the majority of key enzymes involved in lignin biosynthesis was upregulated by BR-pretreatment and P. sojae infection, and lignin accumulation was faster in BR-pretreated soybeans than in untreated controls. Additionally, accumulation of lignin was consistent with these enzyme expressions levels and resistance phenotype. These findings advance the understanding of the role of BRs in the interaction between soybeans and P. sojae.

Heat shock protein 90 s (Hsp90s), one of the most conserved and abundant molecular chaperones, is an essential component of the protective stress response. A previous study reported at least 12 genes in the GmHsp90s family in soybean and that GmHsp90A2 overexpression enhanced thermotolerance in Arabidopsis thaliana. Here, we investigate the roles of GmHsp90A2 in soybean by utilizing stable transgenic soybean lines overexpressing GmHsp90A2 and mutant lines generated by the CRISPR/Cas9 system. The results showed that compared with wild-type plants (WT) and empty vector control plants (VC), T3 transgenic soybean plants overexpressing GmHsp90A2 exhibited increased tolerance to heat stress through higher chlorophyll and lower malondialdehyde (MDA) contents in plants. Conversely, reduced chlorophyll and increased MDA contents in T2 homozygous GmHsp90A2-knockout mutants indicated decreased tolerance to heat stress. GmHsp90A2 was found to interact with GmHsp90A1 in yeast two-hybrid assays. Furthermore, subcellular localization analyses revealed that GmHsp90A2 was localized to the cytoplasm and cell membrane; as shown by bimolecular fluorescence complementation (BiFC) assays, GmHsp90A2 interacted with GmHsp90A1 in the nucleus and cytoplasm and cell membrane. Hence, we conclude that GmHsp90A1 is able to bind to GmHsp90A2 to form a complex and that this complex enters the nucleus. In summary, GmHsp90A2 might respond to heat stress and positively regulate thermotolerance by interacting with GmHsp90A1.

The mediator complex is an essential link between transcription factors and RNA polymerase II, and mainly functions in the transduction of diverse signals to genes involved in different pathways. Limited information is available on the role of soybean mediator subunits in growth and development, and their participation in defense response regulation. Here, we performed genome-wide identification of the 95 soybean mediator subunits, which were unevenly localized on the 20 chromosomes and only segmental duplication events were detected. We focused on GmMED16-1, which is highly expressed in the roots, for further functional analysis. Transcription of GmMED16-1 was induced in response to Phytophthora sojae infection. Agrobacterium rhizogenes mediated soybean hairy root transformation was performed for the silencing of the GmMED16-1 gene. Silencing of GmMED16-1 led to an enhanced susceptibility phenotype and increased accumulation of P. sojae biomass in hairy roots of transformants. The transcript levels of NPR1, PR1a, and PR5 in the salicylic acid defense pathway in roots of GmMED16-1-silenced transformants were lower than those of empty-vector transformants. The results provide evidence that GmMED16-1 may participate in the soybean–P. sojae interaction via a salicylic acid-dependent process.

Background: The WRKY proteins are a superfamily of transcription factors and members play essential roles in the modulation of diverse physiological processes, such as growth, development, senescence and response to biotic and abiotic stresses. However, the biological roles of the majority of the WRKY family members remains poorly understood in soybean relative to the research progress in model plants. Results: In this study, we identified and characterized GmWRKY40, which is a group IIc WRKY gene. Transient expression analysis revealed that the GmWRKY40 protein is located in the nucleus of plant cells. Expression of GmWRKY40 was strongly induced in soybean following infection with Phytophthora sojae, or treatment with methyl jasmonate, ethylene, salicylic acid, and abscisic acid. Furthermore, soybean hairy roots silencing GmWRKY40 enhanced susceptibility to P. sojae infection compared with empty vector transgenic roots. Moreover, suppression of GmWRKY40 decreased the accumulation of reactive oxygen species (ROS) and modified the expression of several oxidation-related genes. Yeast two-hybrid experiment combined with RNA-seq analysis showed that GmWRKY40 interacted with 8 JAZ proteins with or without the WRKY domain or zinc-finger domain of GmWRKY40, suggesting there were different interaction patterns among these interacted proteins. Conclusions: Collectively, these results suggests that GmWRKY40 functions as a positive regulator in soybean plants response to P. sojae through modulating hydrogen peroxide accumulation and JA signaling pathway.

Soybean is one of the most important economic and oil crops across the world. Phytophthora root rot (PRR), caused by Phytophthora sojae (P. sojae), is a major disease in most soybean-growing regions worldwide. Here, we investigated metabolic changes in hypocotyls of two soybean lines, Nannong 10-1 (resistant line, R) and 06-070583 (susceptible line, S), at two time points (12 and 36 hpi) after P. sojae infection and metabolic differences between the R line and the S line. In total, 90 differentially accumulated metabolites (DAMs) were identified after P. sojae infection; the levels of 50 metabolites differed between the R line and the S line. There are 28 DAMs that not only differentially accumulated between the R line and the S line but also differentially accumulated after P. sojae infection. Based on the changes of these DAMs in response to P. sojae infection in different lines and at different timepoints, and the differences in the contents of these DAMs between the R line and the S line, we speculated that DAMs, including sugars (monosaccharides and oligosaccharides), organic acids (oxalic acid, cumic acid), amino acid derivatives, and other secondary metabolites (mannitol, octanal, hypoxanthine, and daidzein etc.) may participate in the metabolic-level defense response of soybean to P. sojae. In this study, an integrated pathway-level analysis of transcriptomics (obtained by RNA-Seq) and metabolomics data illustrated the poor connections and interdependencies between the metabolic and transcriptional responses of soybean to P. sojae infection. This work emphasizes the value of metabolomic studies of plant-pathogen interactions and paves the way for future research of critical metabolic determinants of the soybean-P. sojae interaction.

The seed hardness of vegetable soybean (VSB) is generally regarded as an important quality characteristic that contributes largely to its processing and mouthfeel. However, the genetic control of it is still a gray area. To identify the dynamic quantitative trait loci (QTLs) and detect the genetic relationship between seed hardness and growth period traits at the QTL level, conditional and unconditional QTL analyses were performed using a population of 184 recombinant inbred lines in 2015, 2016 and 2017. For seed hardness at stage 1 to stage 4 (W1–W4), 12 and 8 QTLs were identified by unconditional and conditional mapping, respectively. The comparative analyses between unconditional and conditional mapping uncovered three types of dynamic QTLs underlying seed hardness in the development of VSB. These results demonstrated that genes underlying seed hardness were actively expressed in the interval between stage 2 and stage 3, which was in parallel with the mass filling period in the development of soybean seeds. For seed hardness at R6 stage (W), 11 unconditional QTLs were detected. When W was conditioned on the number of days after sowing to R6 stage (DAS), the number of days after flowering to R6 stage (DAF) and flower time (FT), 11, 2, and 2 conditional QTLs were identified, respectively. Four types of unique QTLs distinguished the contributions of DAS, DAF and FT to the genetic effects of W. Of these, uqW.D1b-1 and uqW.A1-2 control W with independent of DAS or FT. Hence, they would be valuable for the selection softer seed lines, without the simultaneous depression of growth period traits even though there exist significant positive correlation between them. The loci identified by conditional and unconditional QTL analyses may be useful for the improvements of decreased seed hardness with the best balance of growth period through marker assisted selection (MAS).

L-Ascorbic acid（As A） plays an important role in plants and animals. In plants, GDP-D-mannose pyrophosphorylase（GMP） is essential in the As A biosynthetic pathway. However, little is known about the genes encoding GMP in soybean and here we report genetic and functional analysis of the Gm GMP1（Glycine max GDP-D-mannose pyrophosphorylase 1） gene in this species. Gm GMP1 encoded a GDP-mannose pyrophosphorylase and exhibited higher transcript levels in the leaf than in the root, stem, flower, and seed. Transcript of this gene was ubiquitous in the vegetative and reproductive organs, and was induced by abiotic stress and light. Increasing expression of Gm GMP1 in Arabidopsis and soybean through an overexpressing approach caused pronounced enhancement of As A content, and was implicated in lowering the superoxide anion radical content and lipid peroxidation levels in Arabidopsis, and conferring tolerance to osmotic and high salt stresses during seed germination. The present study represents the first systematic determination of soybean genes encoding GDP-mannose pyrophosphorylase and provides useful evidence for the functional involvement of Gm GMP1 in control of As A content and conferring tolerance to osmotic and salt stress.

Plant height (PH) is an important agronomic trait and is closely related to yield in soybean [Glycine max (L.) Merr.]. Previous studies have identified many QTLs for PH. Due to the complex genetic background of PH in soybean, there are few reports on its fine mapping.

[目的]WRKY转录因子与植物的生物和非生物胁迫应答密切相关.通过对大豆WRKY转录因子基因GmWRKY148的克隆及在大豆发状根中过表达后对疫霉根腐病抗性的分析,探究大豆与大豆疫霉菌互作的作用机理.[方法]以拟南芥的AtWRKY44序列为探针,利用同源克隆的方法在大豆Williams 82的根部组织中得到其同源基因Glyma.14G199800,命名为GmWRKY148.对GmWRKY148蛋白进行系统进化树分析;利用qRT-PCR方法分析该基因在大豆的根、茎、叶、子叶和接种大豆疫霉菌不同时间点的转录水平;利用双酶切的方法将GmWRKY148完整的CDS序列连接到植物过表达载体pBinGFP2中,利用基因枪法将重组质粒转化到洋葱表皮细胞中,进行亚细胞定位分析.利用发根农杆菌K599介导的遗传转化体系,经过GFP荧光筛选和qRT-PCR检测,获得大豆过表达GmWRKY148的阳性发状根(OE-GmWRKY148)和转入pBinGFP2空载体(EV)的阴性对照发状根.对过表达GmWRKY148发状根和阴性对照发状根接种大豆疫霉菌,统计病斑长度、疫霉积累量和卵孢子萌发情况.[结果]GmWRKY148的CDS序列全长为999 bp,编码332个氨基酸,等电点为7.61.系统进化分析发现,GmWRKY148与菜豆(Phaseolus vulgaris)、蒺藜苜蓿(Medicago truncatula)的WRKY转录因子亲缘关系十分相近,且与菜豆的亲缘关系最近.亚细胞定位结果显示,GmWRKY148定位在细胞核中.组织表达分析显示,GmWRKY148在根中的表达量最高,在茎和叶中次之,在子叶中最低.荧光定量PCR结果表明,接种大豆疫霉菌P6497后,在感病品种Williams和抗病品种Williams 82(含有Rps1k)中,GmWRKY148受诱导逐渐上调表达,在侵染24 h后表达水平均达到最高,但在Williams 82中的上调倍数更高.对过表达GmWRKY148和转空载体的大豆阳性发状根分别接种大豆疫霉菌P6497的菌丝块,比较接种24 h后的病斑长度和疫霉积累量,结果显示,与对照EV相比,过表达GmWRKY148大豆阳性发状根的病斑长度显著变短,疫霉积累量显著降低.对过表达GmWRKY148和EV的大豆阳性发状根分别接种疫霉菌P6497的游动孢子,并在接种后24、36和48 h用显微镜观察菌丝的侵染及卵孢子萌发数量,统计结果显示,过表达GmWRKY148的大豆阳性发状根与对照EV相比,菌丝的侵染率及卵孢子萌发率均显著降低.[结论]GmWRKY148参与调控大豆与大豆疫霉的互作,能够增强大豆对大豆疫霉菌的抗性.

[Objective] The plant hormone ethylene involved in plant growth,development,biotic and abiotic stress processes.The CONSTITUTIVE TRIPLE RESPONSE1 gene acts as a key negative regulator of ethylene receptors and participates in ethylene signal transduction pathway by combining ethylene receptor.In order to conduct a preliminary study on the function of GmCTR1,GmCTR1 was cloned and its expression was analyzed,and then transformed into soybean hairy roots for analyzing resistance to Phytophthora root rot of soybean.[Method] Based on the sequence ofAtCTR1 (AT5G03730),Glyma.13G151100 which with the highest homology was selected by BLAST,and it was named GmCTR1.The coding sequence of GmCTR1 was isolated from Williams82.Sequence alignment,phylogenetic analysis were performed.The expression level of GmCTR1 upon infection of Phytophthora sojae was analyzed by qRT-PCR.The plant overexpression vector pBinGFP2:GmCTR1 was constructed.Then the biological function of GmCTR1 against P.sojae was explored through transforming soybean hairy roots in agrobacterium-mediated method.The transgenic overexpressing hairy roots and empty-vector hairy roots were obtained by GFP fluorescence screening.Then the lesion length,accumulation of P.sojae and the relative expression level of resistance related genes were measured.[Result]Based on the sequence of AtCTR1 (AT5G03730),the gene Glyma.13G151100 which with the highest homology was selected by BLAST,and it was named GmCTR1.The coding sequence of GmCTR1 was isolated from Williams82.The CDS of GmCTR1 is 2 511 bp in length.GmCTR1 is a serine/threonine protein kinase encoding 836 amino acids.The molecular weight is 92.35 kD,and the isoelectric point is 6.51.Multiple sequence alignment of GmCTR1 and other CTRls showed that GmCTR1 contains the typical domain of CTR1 protein.Phylogenetic analysis indicated that the CTR1 s from Phaseolus vulgaris,Medicago truncatula were highly similar to GmCTR1 which located in the same branch.qRT-PCR analysis showed that the expression level of GmCTR1 was up-regulated upon infection by P.sojae.There was the highest expression level at 48 h post infection,and then the expression level decreased slightly.The CDS of GmCTR1 was constructed into the overexpression vector pBinGFP2.The recombinant plasmid was confirmed by bacteria PCR and enzyme digested.After inoculation of P.sojae,the resistance was significantly decreased in overexpressed hairy roots.Compared with the empty-vector hairy roots,there are longer lesion length at 36 hpi.Expression analysis showed that there are more accumulation of P.sojae in overexpressing hairy roots.Besides,the expression level of resistance related genes is significantly reduced in overexpressing hairy roots.[Conclusion] GmCTR1 may act as a negative regulator in the interactions between soybean and the P.sojae.