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Abstract Theaus(Oryza sativaL.) varietal group comprises of aus, boro, ashina and rayada seasonal and/or field ecotypes, and exhibits unique stress tolerance traits, making it valuable for rice breeding. Despite its importance, the agro-morphological diversity and genetic control of yield traits inausrice remain poorly understood. To address this knowledge gap, we investigated the genetic structure of 181ausaccessions using 399,115 SNP markers and evaluated them for 11 morpho-agronomic traits. Through genome-wide association studies (GWAS), we aimed to identify key loci controlling yield and plant architectural traits. Our population genetic analysis unveiled six subpopulations with strong geographical patterns. Subpopulation-specific differences were observed in most phenotypic traits. Principal component analysis (PCA) of agronomic traits showed that principal component 1 (PC1) was primarily associated with panicle traits, plant height, and heading date, while PC2 and PC3 were linked to primary grain yield traits. GWAS using PC1 identifiedOsSAC1on Chromosome 7 as a significant gene influencing multiple agronomic traits. PC2-based GWAS highlighted the importance ofOsGLT1and OsPUP4/ Big Grain 3 in determining grain yield. Haplotype analysis of these genes in the 3,000 Rice Genome Panel revealed distinct genetic variations inausrice. In summary, this study offers valuable insights into the genetic structure and phenotypic diversity ofausrice accessions. We have identified significant loci associated with essential agronomic traits, withGLT1, PUP4, andSAC1genes emerging as key players in yield determination.
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Assessing genome‐wide adaptations associated with range expansion in the pink rice borer, Sesamia inferens
Abstract Understanding the genetic basis of adaptive evolution following habitat expansion can have important implications for pest management. The pink rice borer (PRB),Sesamia inferens(Walker), is a destructive pest of rice that was historically restricted to regions south of 34° N latitude in China. However, with changes in global climate and farming practices, the distribution of this moth has progressively expanded, encompassing most regions in North China. Here, 3 highly differentiated subpopulations were discovered using high‐quality single‐nucleotide polymorphism and structural variant datasets across China, corresponding to northern, southern China regions, and the Yunnan‐Guizhou Plateau, with significant patterns of isolation by geographic and environmental distances. Our estimates of evolutionary history indicate asymmetric migration with varying population sizes across the 3 subpopulations. Selective sweep analyses estimated strong selection at insect cuticle glycine‐rich cuticular protein genes which are associated with enhanced desiccation adaptability in the northern group, and at the histone‐lysine‐N‐methyltransferase gene associated with range expansion and local adaptation in the Shandong population. Our findings have significant implications for the development of effective strategies to control this pest.
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- Award ID(s):
- 2147812
- PAR ID:
- 10502090
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Insect Science
- ISSN:
- 1672-9609
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1111/1744-7917.13320
