QTL Mapping for Plant Height Using Chromosome Segment Substitution Lines in Upland Cotton

Abstract

Chromosome segment substitution lines(CSSLs) were developed using Gossypium hirsutum var. CCRI36 as the recipient parent and G. barbadense var. Hai 1 as the donor parent. For mapping stable QTLs associated with plant height, three CSSL populations were planted in five environments(BC5F3, BC5F3:4, and BC5F3:5 in Anyang, Henan in 2009, 2010, and 2011, respectively, and BC5F3:5 in Shihezi, Xinjiang and Liaoyang, Liaoning in 2011) for phenotypic evaluation. The result showed that the transgressive ratio in different environments ranged from 53.43% to 88.97%. Using SSR data based on 408 individuals from BC5F3 and a linkage map constructed earlier that covers 5088.28 cM of cotton genome with 2280 SSR markers in 26 linkage groups, a total of 16 QTLs associated with plant height were detected, which were mapped on 10 chromosomes. Each QTL explained phenotypic variance from 7.35% to 13.17%. Seven QTLs were detected in at least two environments. Locus qPH-15-19 close to marker MUSS563 was identified in one environment, but the marker has been reported to be linked to a QTL for plant height. These stablly expressed QTLs could be applied in the marker assisted selection, fine QTL mapping and gene cloning.