Abstract

The current research studied the F3 and F4 population derived from MAS25 (Aerobic rice) X IB370 (Lowland Basmati) for different physio-morphological traits under water limited aerobic condition in field and net house. Frequency distribution curves for various physio-morphological and root traits were parabolic and in some cases, curves were partially inclined towards the respective aerobic rice parent. Phenotypic correlation coefficient analysis showed significant positive correlation between grain yield per plant and different yield related traits yield-related attributes. These mapping population contains all types of allelic variations for BAD2A locus similar to the basmati (585 and 257 bp) or non-Basmati (585 and 355 bp) and heterozygous (585, 355 and 257 bp), respectively. Out of 604 SSR markers well distributed on 12 rice chromosomes, 70 markers showed polymorphism in parental rice genotypes and were used to assess the genetic diversity. The NTSYS-pc UPGMA tree cluster analysis and two dimensional PCA scaling showed that the populations were quite divergent and segregation among them were interspersed between the parents. Composite Interval Mapping analysis (WinQTL Cartographer 2.5) using SSR databases of various populations led to the mapping of 7 large-effect QTLs for different yield related traits in both mapping populations. Many superior genotypes having higher or comparable grain yield, and other yield related traits than the parental genotypes with intact Basmati specific BAD2A allele in homozygous and heterozygous conditions were selected for potential stable aerobic Basmati rice genotypes.

Keywords: Aerobic rice; SSR marker; QTL; Basmati; Water