YUCCA, belonging to the class B flavin-dependent monooxygenases, catalyzes the rate-limiting step for endogenous auxin synthesis and is implicated in plant-growth regulation and stress response. Systematic analysis of the YUCCA gene family and its stress response benefits the dissection of regulation mechanisms and breeding applications. In this study, 12 YUCCA genes were identified from the mungbean (Vigna radiata L.) genome and were named based on their similarity to AtYUCCAs. Phylogenetic analysis revealed that the 12 VrYUCCAs could be divided into 4 subfamilies. The evidence from enzymatic assays in vitro and transgenetic Arabidopsis in vivo indicated that all the isolated VrYUCCAs had biological activity in response to IAA synthesis. Expression pattern analysis showed that functional redundancy and divergence existed in the VrYUCCA gene family. Four VrYUCCAs were expressed in most tissues, and five VrYUCCAs were specifically highly expressed in the floral organs. The response toward five stresses, namely, auxin (indole-3-acetic acid, IAA), salinity, drought, high temperatures, and cold, was also investigated here. Five VrYUCCAs responded to IAA in the root, while only VrYUCCA8a was induced in the leaf. VrYUCCA2a, VrYUCCA6a, VrYUCCA8a, VrYUCCA8b, and VrYUCCA10 seemed to dominate under abiotic stresses, due to their sensitivity to the other four treatments. However, the response modes of the VrYUCCAs varied, indicating that they may regulate different stresses in distinct ways to finely adjust IAA content. The comprehensive analysis of the VrYUCCAs in this study lays a solid foundation for further investigation of VrYUCCA genes’ mechanisms and applications in breeding.

Mung bean is vulnerable to bruchids (Callosobruchus spp.), resulting in low quality and losses worldwide. Developing resistant cultivars is the most effective, economical, and eco-friendly way to protect mung bean seeds from the damage of bruchids. Previously, we identified two gene loci that are tightly linked with bruchid resistance, which makes new cultivar development possible using molecular assisted selection (MAS). In the present study, marker-assisted backcross (MABC) breeding was employed to introgress the bruchid resistance gene VrPGIP2 locus from the donor parent V2802 into a popular cultivar, Kamphaeng Saen 1. Markers VrBR-SSR013 and DMB-SSR158 were used for foreground selection, and phenotypic selection was used for background selection. Three advanced inbred lines (R67-11, R67-22, and R92-15) carrying the resistance gene VrPGIP2 were developed from the BC₃F₆ population. Further analysis showed that the line R67-22 performed best; it was highly resistant to bruchids and showed excellent agronomic traits in the field. Therefore, R67-22 could be further evaluated in large-scale trials for release as a variety.

Faba bean is an important legume crop consumed as a vegetable or snack food, and its green cotyledons could present an attractive color for consumers. A mutation in SGR causes stay-green in plants. In this study, vfsgr was identified from a green-cotyledon-mutant faba bean, SNB7, by homologous blast between the SGR of pea and the transcriptome of faba bean. Sequence analysis revealed that a SNP at position 513 of the CDS of VfSGR caused a pre-stop codon, resulting in a shorter protein in the green-cotyledon faba bean SNB7. A dCaps marker was developed according to the SNP that caused the pre-stop, and this marker was completely associated with the color of the cotyledon of faba bean. SNB7 stayed green during dark treatment, while the expression level of VfSGR increased during dark-induced senescence in the yellow-cotyledon faba bean HST. Transient expression of VfSGR in Nicotiana. benthamiana leaves resulted in chlorophyll degradation. These results indicate that vfsgr is the gene responsible for the stay-green of faba bean, and the dCaps marker developed in this study provides a molecular tool for the breeding of green-cotyledon faba beans.

The TATA-box binding protein (TBP) and TBP-associated factors (TAFs) constitute the transcription factor IID (TFIID), a crucial component of RNA polymerase II, essential for transcription initiation and regulation. Several TFIID subunits are shared with the Spt–Ada–Gcn5–acetyltransferase (SAGA) coactivator complex. Recent research has revealed the roles of TBP and TAFs in organogenesis and stress adaptation. In this study, we identified 1 TBP and 21 putative TAFs in the mungbean genome, among which VrTAF5, VrTAF6, VrTAF8, VrTAF9, VrTAF14, and VrTAF15 have paralogous genes. Their potential involvement in abiotic stress responses was also investigated here, including high salinity, water deficit, heat, and cold. The findings indicated that distinct genes exerted predominant influences in the response to different abiotic stresses through potentially unique mechanisms. Specifically, under salt stress, VrTBP, VrTAF2, and VrTAF15–1 were strongly induced, while VrTAF10, VrTAF11, and VrTAF13 acted as negative regulators. In the case of water-deficit stress, it was likely that VrTAF1, VrTAF2, VrTAF5–2, VrTAF9, and VrTAF15–1 were primarily involved. Additionally, in response to changes in ambient temperature, it was possible that genes such as VrTAF5–1, VrTAF6–1, VrTAF9–2, VrTAF10, VrTAF13, VrTAF14b–2, and VrTAF15–1 might play a dominant role. This comprehensive exploration of VrTBP and VrTAFs can offer a new perspective on understanding plant stress responses and provide valuable insights into breeding improvement.

Heterosis has been utilized in crops for a long time, and although crop fertility is the basis for the utilization of heterosis, there is limited information concerning the genic male sterility (GMS) of mungbean. Therefore, based on the genic male sterile mutant, M₁, obtained by EMS mutagenesis of the Weilyu cultivar, this project used multi-omics analysis to detect the male sterile site and further identify its candidate gene, and then the mechanism of the candidate gene was discussed. As a result, one locus region (Chr5: 6,835,001–6,935,000 bp) associated with GMS was identified, and nine genes were found within the 100 Kb region. The candidate gene, VrCYCA1, around the above loci had a TATA box deletion approximately 4.7 Kb upstream of the gene, and this was evidenced by comparative genomics, transcriptome analysis, and RT-qPCR analysis. The expression level of VrCYCA1 was significantly downregulated (log₂FC = −2.06, p-value = 0.025) in the ms lines compared with the control group. Moreover, 6653 genes showed differential expression between the Weilyu lines and mutant lines as well as 165 metabolites with significant differences in their concentration levels. Among those differentially expresses genes, 226 were annotated with functional categories involved in flowering and endosperm development, and six genes had protein–protein interactions with VrCYCA1. Seven categories of metabolites and seven genes participated in the relationship between reproductive growth and vegetative growth, which might have caused the sterility of mungbean in the mutant plants. This study used multi-omics data to mine a mungbean GMS-related gene, VrCYCA1, and constructed a GMS genetic network to explore the molecular mechanism of VrCYCA1. The results lay a solid foundation for further molecular biology research and utilization in mungbean male sterility.

Background/Objectives: Salinity stress limits agricultural production and threatens global food security. Faba bean (Vicia faba L.) is an important legume crop, and identifying salt-stress-responsive genes may support an improvement in salt response. This study aimed to identify intronless genes in faba bean, screen candidate genes associated with salt-stress responses, and develop a KASP marker for salt-response evaluation. Methods: Intronless genes were identified from the faba bean reference genome. Transcriptome analysis was conducted in roots and leaves of two cultivars, Sucan 4 and Yundou 1183, under 150 mM NaCl treatment and control conditions. Candidate genes were examined by expression analysis, functional annotation, PPI prediction, and a luciferase complementation assay. A KASP marker was developed from an SNP within the VfERF1A locus and tested in 97 accessions. Results: A total of 7581 intronless genes were identified, accounting for 20.69% of annotated genes. Fifteen intronless genes were significantly differentially expressed in both roots and leaves of the two cultivars under salt treatment. Functional annotation suggested that VfERF1A and VfHSP17.8 may be involved in salt-stress responses. PPI prediction and the LUC assay provided preliminary support for a possible association of VfERF1A with VfEIN2. The VfERF1A-based KASP marker showed clear genotype clustering, and the two homozygous classes differed significantly in QYmax, relative shoot fresh weight, and relative plant height under salt treatment (p < 0.05). The preliminary predictive accuracy for QYmax was 86.36%. Conclusions: These results provide a genome-wide resource of intronless genes in faba bean, identify candidate genes associated with salt-stress responses, and describe a preliminary KASP marker associated with salt-response traits. Further validation in independent populations, under diverse environmental conditions, and with additional functional evidence is still required.