There is currently international interest in applying DNA barcoding as a tool for plant species discrimination and identification. In this study, we evaluated the utility of four candidate plant DNA barcoding regions [rbcL,matK,trnL-F, and internal transcribed spacer (ITS)] in seven genera of Gramineae includingAgropyron,Bromus,Elymus,Elytrigia,Festuca,Leymus, andLolium. Fourteen accessions were analyzed, andmatKandITSshowed the highest species, subspecies, and variety discriminatory power, each resolving 11 accessions. Species discrimination usingrbcLandtrnL-Fwas lower, resolving 7 and 8 accessions, respectively. Subspecies and variety discrimination usingrbcLandtrnL-Fcould not identify 4 accessions ofAgropyron. A technical system can be established using the proposed DNA barcode to rapidly and reliably identify the seven genera of Gramineae. This study serves as a “useful reference” for identifying the genetic diversity of grass germplasm resources. DNA barcoding can be utilized to uncover the relatives of different species within the same family or between different families. It can also be used to determine the related groups of important herbage, turfgrass, and crops and provide crucial background information for discovering excellent genes and improving existing crop varieties.

Leymus chinensis is a grass species in the family Triticeae that is found in the Eurasian grassland region and is known for its outstanding ecological advantages and economic value. However, the increasing adoption of photovoltaic agriculture has modified the light environment for the grass, markedly inhibiting its photosynthesis, growth, and yield. This study used physiological and transcriptomic analyses to investigate the complex response mechanisms of two L. chinensis genotypes (Zhongke No. 3 [Lc3] and Zhongke No. 5 [Lc5]) under shading stress. Growth phenotype analysis revealed the superior growth performance of Lc3 under shading stress, evidenced by enhanced plant height and photosynthetic parameters. Additionally, differentially expressed genes (DEGs) were predominantly enriched in starch and sucrose metabolism and glycolysis/gluconeogenesis pathways, which were the most consistently enriched in both L. chinensis genotypes. However, the flavonoid biosynthesis and galactose metabolism pathways were more enriched in Lc3. Weighted gene co-expression network analysis identified the LcGolS2 gene, which encodes galactinol synthase, as a potential hub gene for resistance to shade stress in comparisons across different cultivars and shading treatments. The use of qRT-PCR analysis further validated the genes involved in these pathways, suggesting that they may play critical roles in regulating the growth and development of L. chinensis under shading conditions. These findings provide new insights into the molecular mechanisms underlying the growth and development of L. chinensis under different shading stress conditions.

The expression of genes specific to floral organ is important for the floral organ formation and development in Medicago truncatula. Screening of the genes specifically expressed in M. truncatula flowers and comparing the expression patterns of their orthologous homologous genes among different model plants can provide novel insights into the functions of these genes in controlling the floral organ development in M. truncatula. According to the expression profile data of PISTILLATA (PI), we screened 97 genes specifically expressed in M. truncatula floral organs (ratio≥10 and Z≥7.9). Their homolog genes were also identified in Arabidopsis thaliana, soybean (Glycine max L.), Lotus japonicus, and rice (Oryza sativa L.). The results of comparing the gene expression levels, the gene expression patterns, and the gene functions among these species indicated that the expression variation of the orthologous homolog genes was small in the kindred species and was great in distant species. Furthermore, we compared the cis-acting regulatory elements of the genes, which had large expression variation among different plants. These results suggest that the great discrepancy of the orthologous homolog gene expression caused by the different character of cis-element in the promoter region.

Vicia villosa Roth var. glabrescens (smooth vetch) is an economically important legume cover crop valued for its nitrogen-fixing capacity, high biomass yield, and adaptability across diverse agroecosystems. Here, we present a chromosome-scale, high-quality genome assembly of V. villosa var. glabrescens, constructed using PacBio HiFi sequencing combined with Hi-C scaffolding. The assembly spans 3.70 Gb with a scaffold N50 of 4.69 Mb and exhibits lower heterozygosity (0.9%) compared to V. villosa Roth (3.1%). Genome analysis revealed significant expansion of long terminal repeat retrotransposons (LTR-RTs), as well as lineage-specific proliferation of miniature inverted-repeat transposable elements (MITEs) in V. villosa var. glabrescens. Comparative genomics with V. villosa Roth highlighted gene family expansions associated with trichome development, providing insights into the genetic basis of morphological and adaptive differences within the Vicia species. This reference genome provides a foundational resource for accelerating the breeding of V. villosa varieties with enhanced agronomic traits and contributes to a broader understanding of legume genomics and plant genome evolution.