Detection of quantitative trait loci for cold tolerance at the bud bursting stage by using chromosome segment substitution lines in rice (Oryza sativa).

The cold tolerance at the bud bursting stage (CTB) were evaluated at 5℃ by using a set of 95 chromosome segment substitution lines (CSSLs) derived from indica rice 9311 and japonica rice Nipponbare. The results showed that six CSSLs had slightly stronger CTB than 9311. Total four quantitative trait loci (QTLs) for CTB were preliminary mapped on chromosomes 5 and 7 by substitution mapping. qCTB-5-1, qCTB-5-2 and qCTB-5-3 were mapped in the region of RM267-RM1237,RM2422-RM6054 and RM3321-RM1054, which were 21.3 cM, 27.4 cM and 12.7 cM in genetic distance on rice chromosome 5, respectively. qCTB-7 was mapped in the region of RM11-RM2752, which was 6.8 cM in genetic distance on rice chromosome 7.