Discovery of the loci associated with the test weight and capsule seed weight variation in Sesame (Sesamum indicum L.).

Abstract

Genetic improvement on the economical yield-related traits of sesame is crucial for desirable trait selection for analysis. Hence, understanding the genetic basis of genes regulating test weight and capsule seed weight traits and its association with seed yield is crucial to guide breeding program. The objective of the study was to understand natural variations and discover the genetic markers and key genes regulating test weight (TW) and capsule seed weight (CSW) in sesame. 401 diverse sesame genotypes were evaluated under four and two environments for test weight and capsule seed weight, respectively. Results revealed diverse genetic variations on studied traits cross environments. The total TW ranged from 496.23 to 672.92 g L^- 1, 436.15 to 678.20 g L^- 1 478.79 to 672.92 g L^- 1, and 450.40 to 682.61 g L^- 1 in 2023Wuhan, 2019 Jinxian, 2022Wuhan, and 2019Zhumadian environments, respectively. Whereas, CSW varied from 0.02 to 0.29 g in 2023Linqing and 0.05 to 0.30 g in 2023Wuhan. The GWAS detected four (3 SNPs and Indel) and two (1 SNP and InDel) significant SNP and InDel loci associated with TW and CSW, respectively. Of the SNPs, SNP11:142842 was more stable and associated with TW across the four environments. Moreover, SNP7:5945502, and InDel10:18621286 were identified for CSW in Linqing and Wuhan environments, respectively. Candidate genes SINPZ1100015, SINPZ0700254 and SINPZ1001450 were associated with TW and CSW and may represent the major candidate effect gene for the studied traits in sesame. Our findings provide insights into natural variation in sesame for TW and CSW and valuable information for markers-assisted breeding in sesame and other crops.