QTL mapping of dehiscence length at the basal part of thecae related to heat tolerance of rice (Oryza sativa L.)

Abstract

Quantitative trait loci (QTL) for the length of the dehiscence that forms at the base of the anther [basal dehiscence length (BDL)] in rice (Oryza sativa L.) were analyzed using chromosome segment substitution lines (CSSLs) developed from 9311 (as the recipient) and Nipponbare (as the donor). Using composite interval mapping with QTL Icimapping software, seven QTLs were detected on Chr. 2, 7, 8, 9, 10, and 11. These QTLs explained 6.49–18.15 % of the total phenotypic variation for BDLin CSSLs during 2012. qBDL8, qLDB10 and qBDL11 were derived from 9311 allele. The other four QTLs had negative effects on BDL and were derived from Nipponbare alleles. qBDL2-2, qBDL7, qBDL8, qBDL10 and qBDL11 were consistent with some heat tolerance QTLs mapped with different indexes and populations by other researchers. Among them, qBDL2-2 and qBDL10 were found to have significant effect on heat tolerance in populations derived from Nipponbare in previous reports, which suggests that those two QTLs were stable in different environments and can be used in heat tolerance breeding. The results indicated that QTL analysis of the long basal dehisce trait might be an effective index to identify the heat tolerance of rice in an ordinary environment.