Genetic mapping for grain quality and yield-attributed traits in Basmati rice using SSR-based genetic map

Abstract

Rice grain shape and nutritional quality traits have high economic value for commercial production of rice and largely determine the market price, besides influencing the global food demand for high-quality rice. Detection, mapping and exploitation of quantitative trait loci (QTL) associated with kernel elongation and grain quality in Basmati rice is considered as an efficient strategy for improving the kernel elongation and grain quality trait in rice varieties. Genetic information in rice for most of these traits is scanty and needed interventions through the use of molecular markers. A recombinant inbred lines (RIL) population consisting of 130 lines generated from the cross involving Basmati 370, a superior quality Basmati variety and Pusa Basmati 1121, a Basmati derived variety were used to map the QTLs for 9 important grain quality and yield related traits. Correlation studies showed that various components of yield show a significant positive relationship with grain yield. A genetic map was constructed using 70 polymorphic simple sequence repeat (SSR) markers spanning a genetic distance of 689.3 cM distributed over 12 rice chromosomes. Significant variation was observed and showed transgressive segregation for grain quality traits in RIL population. A total of 20 QTLs were identified associated with nine yield and quality traits. Epistatic interactions were also identified for grain quality related traits indicating complex genetic nature inheritance. Therefore, the identified QTLs and flanking marker information could be utilized in the marker-assisted selection to improve kernel elongation and nutritional grain quality traits in rice varieties.