Exploring the effects of qDTY2.1 genomic regions on yield related traits in rice (Oryza sativa L.) under well watered conditions

Abstract

The quantitative trait locus qDTY2.1 regulates yield under drought stress in rice. This study investigates the role of qDTY2.1 on yield-related traits in rice under well-watered conditions. For comparison, a large qDTY2.1 region (Chr02: 10.7–17.68 Mbp) and its fine-mapped segment (Chr02:10.7–11.4 Mbp) were compared to understand the linkage drag effects. Out of 432 F2 population derived from a cross between Swarna Sub1 and CR Dhan 801 (qDTY2.1 and qDTY3.1), 132 lines possessing only the qDTY2.1 were evaluated for the yield-related traits in well-watered conditions. This analysis showed similar effects for the large (Chr02: 10.7–17.68 Mbp) and fine-mapped (Chr02:10.7–11.4 Mbp) qDTY2.1 region. Besides, the effect of the six haplotypes (two parental and four recombinants) significantly differed (p <0.05) for productive tillers, unfilled grains, and 100-seed weight. Based on the expression in the panicle stage, two candidate genes, namely, a meristem regulator gene (Os02g0293300; OsFDML1; Chr02:11.15 Mb) annotated as Arabidopsis homolog of factor of DNA methylation 1 and calcineurin B-like (Os02g0291000; OsCBL7; Chr02:11.01 Mb), were identified, which may regulate the yield-related traits in well-watered conditions. Thus, the present findings indicated the statistical effect of large and fine-mapped qDTY2.1 and their haplotypes in affecting the yield-related traits in well-watered conditions.