The kinesin (KIN) gene family is a subgroup of motor proteins. It plays a critical role in plant development and responses to environmental stresses. However, their function in soybean salt tolerance has yet to be clearly defined. This study employed bioinformatics approaches and identified 139 kinesin family members in the soybean genome. These 139 genes were classified into 10 subgroups, unevenly distributed across the chromosomes. The promoter regions of GmKIN genes harbored several stress-responsive elements, and segmental duplication was the primary driver of the expansion of the GmKIN gene family. Based on publicly available RNA-seq data, we studied the response patterns of 139 GmKIN genes to salt stress and found that 20 KIN genes in soybeans were upregulated after salt stress, with GmKIN114, GmKIN102, GmKIN109, and GmKIN99 showing more than a threefold increase in their expression under salt stress. Using quantitative fluorescence PCR, transgenic yeast, and a transgenic hairy root system, we preliminarily validated the salt tolerance functions of the four KIN genes in soybeans. This study probed into the GmKIN gene family in soybean, offering valuable insights into the functional roles of these genes in stress adaptation.

The cellulose synthase (CS) superfamily, comprising the cellulose synthase (CESA) and cellulose synthase-like (CSL) families, plays crucial roles in plant response to abiotic stresses, growth and development. However, there are few reports on the biological functions of CSs in soybean. In this study, 80 soybean CS members were identified and classified into seven subfamilies. Collinearity analyses revealed that the segmental duplication is likely the primary driver for the expansion of CS superfamily in soybean. The abundant stress-responsive and growth-related cis-acting elements in the promoter regions of soybean CS genes suggest their potential functions. Notably, GmCESA1 exhibited significantly higher expression levels in drought-tolerant soybean under drought stress. Soybean plants with lower GmCESA1 expression via virus-induced gene silencing (VIGS-GmCESA1) were less drought-tolerant than the control plants (VIGS-EV), showing reduced relative water content and dry weight than VIGS-EV under drought stress. Furthermore, VIGS-GmCESA1 soybean plants displayed reduced plant height under both well-watered and drought-stressed conditions. Our findings highlight that GmCESA1 has pleiotropic functions in regulating both drought tolerance and growth in soybean, contributing to our knowledge on CS and providing a valuable gene to breed drought-tolerant soybean in the future.

The Aldehyde Dehydrogenase (ALDH) superfamily comprises a group of NAD⁺ or NADP⁺-dependent enzymes that play essential roles in responding to abiotic stresses in plants. In Brassica napus L., however, the increasing frequency of extremely low temperatures during winter in recent years has significantly affected both yield and quality. This study conducted a genome-wide screening of ALDH superfamily genes, analyzing their gene structures, evolutionary relationships, protein physicochemical properties, and expression patterns under low-temperature stress to explore the function of the ALDH superfamily gene in cold tolerance in Brassica napus L. A total of six BnALDH genes with significant differences in expression levels were verified utilizing quantitative real-time polymerase chain reaction (qRT-PCR), revealing that BnALDH11A2, BnALDH7B2, BnALDH3F5, BnALDH12A3, BnALDH2B6, and BnALDH7B3 all exhibited higher expression in cold-tolerant material 24W233 compared with cold-sensitive material 24W259. Additionally, a single nucleotide polymorphism (SNP) in the BnALDH11A2 promoter region shows differences between the cold-tolerant (24W233) and the cold-sensitive (24W259) Brassica napus varieties, and it may be associated with the cold tolerance of these two varieties. This comprehensive analysis offers valuable insights into the role of ALDH family genes in low-temperature stress adaptation in Brassica napus and offers genetic resources for the development of novel cold-tolerant cultivars.

First pod height (FPH) is a critical agronomic trait in soybean because it directly affects mechanized harvesting efficiency and harvestable yield. Pods below the cutter-bar height are left uncollected, leading to direct seed loss. However, the genetic architecture underlying FPH remains largely underexplored. Here, we conducted a genome-wide association study (GWAS) on FPH data using 386 soybean accessions evaluated across three environments, together with best linear unbiased prediction (BLUP) values. Phenotypic analysis showed that cultivated soybean exhibited significantly greater FPH than wild accessions, consistent with selection for improved harvestability during domestication. Using two GWAS methods, RTM-GWAS and EMMAX, we identified seven stable (detected by the same method at least three times) quantitative trait nucleotides/loci (QTNs/QTLs) significantly associated with FPH. By integrating sequence variation, gene expression, and functional description, we identified GmAIR9 (corresponding to Glyma.09G084300/SoyZH13_09G078900), which encodes a microtubule-associated protein preferentially expressed in stems, as a candidate gene for further investigation. Haplotype analysis of GmAIR9 revealed that haplotype H3 was associated with low FPH and was detected exclusively in wild soybean accessions, whereas haplotype H1 was associated with increased FPH. Moreover, the frequency of H1 increased from 50.00% in wild soybeans to 71.03% in landraces and 83.47% in improved cultivars. These findings provide valuable genetic resources and promising candidate loci for future validation and breeding applications to optimize FPH and improve the suitability of soybean cultivars for mechanized harvesting.