Molecular Breeding最新文献

Pooja and Naveen are popular semidwarf rice varieties of eastern and northeastern India. Bacterial blight disease caused by Xanthomonas oryzae pv. oryzae (Xoo) and lodging lead to yield loss in both genotypes. Considering unique racial composition of Xoo in target regions, five resistance genes (Xa4, xa5, Xa7, xa13 and Xa21) were pyramided in Naveen using IRBB66 as donor. The near isogenic lines (NILs) showed resistant reaction across growing seasons and against multiple Xoo strains. Although plant height of the NILs were similar to Naveen, several tall and semi-tall recombinants appeared from F₂ generation onwards. Molecular profiling confirmed presence of SD1 allele in Naveen, its NILs and the taller recombinant inbred lines (RILs). Xa4 gene improved lodging resistance in both semidwarf NILs and the taller RILs. One non-lodging semi-tall RIL with Xa4 + xa5 + Xa7 + xa13 + Xa21 + SD1 allelic combination with substantially higher yield than both parents and significantly higher yield than check genotypes was released as a new variety CR Dhan 326 after blind multilocation trials. The Xa4 gene also reduced lodging of SD1SD1 RILs developed by crossing CR Dhan 326 with RP-Bio-226 (xa5 + xa13 + Xa21 + sd1). NILs with Xa4 + xa5 + Xa7 + xa13 + Xa21 genes were also developed in Pooja. However, backcrossing led to irreversible loss of semi-dwarfism and presence of SD1 allele was confirmed in Pooja and its NILs. Semidwarf NILs could be developed only after introgression of sd1 allele. The Xa4 gene reduced plant height of both semidwarf and tall NILs. The non-lodging SD1 + Xa4 NILs of Pooja may suit in semi-deep-water ecology, whereas sd1 + Xa4 NILs are suitable for shallow lowlands.

Supplementary information: The online version contains supplementary material available at 10.1007/s11032-026-01633-0.

Reproductive isolation between rice subspecies poses a significant barrier to harnessing heterosis in hybrid breeding. Here, we identified and characterized a novel locus, designated Male Sterility-Related Hybrid Breakdown Locus on Chromosome 1 (MSHB1), through the utilization of chromosome segment substitution lines (CSSLs) derived from crosses between an indica cultivar Huanghuazhan (HHZ) and an aromatic cultivar Basmati Surkh 89 - 15 (BAS). A near-isogenic line, CS004, carrying the BAS-derived MSHB1 ^BAS allele, exhibits complete male sterility, reduced plant height, fewer panicles, and shorter panicle length. Fine mapping localized MSHB1 to a 28.583-kb interval on the short arm of chromosome 1. Genetic complementation confirmed that the MSHB1 allele from HHZ is sufficient to restore fertility. MSHB1 encodes a homolog of Esa1-associated factor 6 (EAF6), which regulates histone acetylation and transcriptional activity. Comparative genomic analyses revealed that functional divergence in promoter activity between duplicated OsEAF6 paralogs (MSHB1 and MSHB12) drives hybrid breakdown. These findings elucidate a molecular mechanism underlying intersubspecific reproductive isolation and highlight MSHB1 as a strategic target for overcoming hybrid sterility to enhance heterosis in rice breeding.

Supplementary information: The online version contains supplementary material available at 10.1007/s11032-025-01630-9.

Interactions between plant roots and complex microbial communities are critical for plant environmental adaptation. Pseudomonas simiae WCS417, a Gram-negative plant growth-promoting rhizobacterium (PGPR), is a model organism in plant-microbe interaction research and featured in over 750 studies since the 1990s. However, the translatome dynamics induced by WCS417 remain poorly understood. This study employed an integrated multi-omics approach, combining transcriptome (RNA-seq) and translatome (RNC-seq) analyses, to systematically investigate the transcriptional and translational regulatory networks in Brassica napus roots during early colonization by WCS417. Our results demonstrate that WCS417 significantly promotes lateral root formation, suppresses primary root elongation, and increases plant biomass. At the molecular level, WCS417 inoculation triggered extensive changes in gene expression and translation at 30 min and 6 h post-inoculation, affecting key processes including phytohormone signaling, cell wall remodeling, immune responses, and abiotic stress adaptation. Notably, although transcript levels of some immune-related genes were downregulated, their translation ratios was significantly enhanced, suggesting that plants maintain basal immunity while facilitating symbiotic establishment. Furthermore, WCS417 dynamically regulated genes involved in nitrogen/phosphorus uptake and core low-temperature response transcription factors in Brassica napus roots. These findings reveal a multi-layered regulatory mechanism by which WCS417 optimizes root system architecture and balances immunity with growth in Brassica napus, providing new insights into plant-microbe interactions.

Supplementary information: The online version contains supplementary material available at 10.1007/s11032-025-01628-3.

Rapid advancements in molecular-level studies have highlighted significant changes and challenges in plant genetic studies. The current research on barley germplasm in China has shed light on the genetic mechanisms behind β-glucan content. In this study, the genotypic variation for 260 barley accessions was examined, with mean β-glucan values ranging from 3.22% to 5.48% across five environments. A genome-wide association study (GWAS) using a general linear model (GLM) identified 55 significant SNP markers on chromosomes 1 H, 3 H, 4 H, 5 H, 6 H, and 7 H, explaining 7.35% to 15.94% of the observed phenotypic variation. Transcriptome sequencing was performed on two contrasting germplasms, revealed 1,880 and 1,160 differentially expressed genes (DEGs) at 14 and 28 days post-anthesis, respectively, with pathways enriched in starch and sucrose metabolism, linking them to β-glucan variation. A new gene, newGene_23124 (1 H), was identified with a functional annotation as a beta-D-glucan exohydrolase was identified as a strong candidate gene. GWAS results identified foundglycosyltransferase family protein genes, HORVU.MOREX.r3.1HG0057970 (1 H), and HORVU.MOREX.r3.3HG0279880 (3 H), which are involved in β-glucan synthesis and cell wall formation. Additionally, the genes HORVU.MOREX.r3.4HG0337820 (4 H) and HORVU.MOREX.r3.5HG0431360 (5 H), encoding for UDP-glycosyltransferase family proteins, were also identified. Furthermore, HORVU.MOREX.r3.7HG0651610 (7 H), encoding a glycosyl hydrolase family 10 protein, was found to influence β-glucan content. In addition to these, several other genes were investigated. Overall, this research provides new insights into the genetic regulation of β-glucan content in barley and lays the foundation for breeding programs aimed at nutritional improvement of the crop.

Supplementary information: The online version contains supplementary material available at 10.1007/s11032-025-01625-6.

Rice serves as a fundamental dietary staple for billions worldwide, but often lacks sufficient nutritional value, particularly in terms of protein and essential amino acids. This abstract offers an overview of the composition, distribution, and recent advancements in protein and amino acid enhancement in rice, highlighting strategies to boost its nutritional profile. Through traditional breeding and modern biotechnological methods, researchers have developed rice varieties with higher levels of key amino acids such as lysine, methionine, and cysteine, along with increased overall protein content. These biofortified rice varieties show promise in combating protein malnutrition and associated health issues, especially in vulnerable communities. However, the successful implementation of biofortification programs requires careful consideration of safety, regulations, environmental sustainability, and socio-economic factors. This emphasizes the need for collaboration among researchers, policymakers, and agricultural stakeholders to ensure widespread adoption and equitable distribution of biofortified rice varieties. Continued research and investment in protein and amino acid enhancement offer significant potential in addressing global malnutrition and improving public health outcomes.