[Initial identification of quantitative trait loci controlling resistance to banded leaf and sheath blight at...

The genetic linkage map was constructed with 146 SSR markers based on a maize population consisting of 229 F2 individuals from the cross R15 (resistant) x 478 (susceptible), covering 1666cM on a total of ten chromosomes, with an average interval length of 11.4 cM. The disease index from the population of 229 F24 lines were evaluated for BLSB resistance under artificial inoculation at elongating stage and heading date. With the method of composite interval mapping (CIM) described in QTL cartographer v2.0 procedure, 9 QTLs among of 17 QTLs were identified on 1, 2, 3, 4, 5, 6 and 10 chromosomes at Jointing Stage, accounting for 3.72% to 9.26% of the phenotypic variance. The other 10 QTLs were identified on 2, 3, 4, 5, 6, 8 and 9 chromosomes at elongating stage and heading date, accounting for 4.27% to 9.27% of the phenotypic variance. Among of them, two QTLs were detected at two stages, which were located between bnlgl600-umc1818 and umc1006-umc1723 on chromosome 2 and 6, respectively. The result indicated that the significant difference about QTL Controlling Resistance between the two stages had a close connection with Developing Stages, which was showed on the resistance of banded leaf and sheath blight in maize. So this result provided new information to the resistance breeding of maize.