Identification and interaction analysis of six agronomic trait loci of rice based on a recombinant inbred population

A recombinant inbred line (RIL) population including 107 stable lines was obtained from a cross between an indica variety ZYQ8 and a japonica variety JX17 of rice (Oryza sativa L.) through successive selfing up to 9 generations. The quantitative trait loci (QTLs) responsible for six agronomic traits (days to heading, plant height, number of spikelets per panicle, number of grains per panicle, 200-grain weight, seed set percentage) were surveyed and analyzed based on the molecular linkage map constructed from this RIL population. All six traits displayed continuous distribution in the RIL population. For days to heading, two QTLs were identified on chromosomes 8 and 12, of which, qHD-8 was a major gene located on chromosome 8. For plant height, two QTLs were identified on chromosome 1 and 4, of which qPH-1 was a major gene located on chromosome 1. Meanwhile, interaction analysis between these QTLs affecting rice productivity was carried out, and the results showed that there were a total of 24 coadaptive interactions affecting days to heading, plant height, number of spikelets per panicle, number of grains per panicle and seed set percentage, explaining 6.2% similar to 10.9% variation respectively.