Identification Of Qtls For Yield-Related Traits Using Two Sets Of Introgression Lines With A Common Donor Parent In Rice

Rice yield is a complex trait that is the major target in rice breeding program. In the present study, two sets of introgression line populations derived from three parents were used to dissect the genetic basis of yield-related traits, explore the genetic background effect on QTL detection and mine pleiotropic QTL for yield-related traits.. Among the three parents, IR75862 was the common donor parent, and Ce258 and Zhongguangxiang1 were two recipient parents. The two introgression line populations were evaluated for yield-related traits in the summer of 2012 at Jingzhou, China. Combined with genotype of the introgression lines, 35 QTLs were detected in all 12 chromosomes except chromosome 5 for eight yield-related traits, including plant height, panicle number per plant, panicle length, filled grain number per panicle, spikelet number per panicle, seed setting rate, thousand grain weight and grain yield per plant, which explained 6.36. - 36.37% of phenotypic variances. No common QTL was detected in the two backgrounds, and seven chromosome regions on chromosomes 2, 3, 4, 6 and 10 had pleiotropic effects on two or more traits, indicating large genetic background effect on expression of QTLs for yield-related traits. Total of 19 (54%) QTLs including newly identified QTLs, qGY3, qFGN10.2 and qSN10 with IR75862 alleles increased yield-related traits. Therefore, it's possible to develop new super rice varieties through introgressing or pyramiding the IR75862 alleles at the pleiotropic QTLs (qPL2.1 and qPL6.1) and novel QTLs (qGY3, qFGN10.2 and qSN10) into Ce258 and Zhongguangxiang1 by marker-assisted selection. (c) 2018 Friends Science Publishers