Genetic analysis of leaffolder resistance in rice.

A double haploid (DH) population, which consists of 120 lines derived from anther culture of a typical indica and japonica hybrid 'CJ06'/'TN1', was used to investigate the genetic basis for rice leaffolder resistance. Using a constructed molecular linkage map, five QTLs for rolled leaves were detected on chromosomes 1, 2, 3, 4, and 8. The positive alleles from CJ06 on chromosomes 3, 4, and 8 increased the resistance to rice leaffolder, and the alleles from TN1 on chromosomes 1 and 2 also enhanced resistance to leaffolder. The interactions between QTLs were identified and tested, and four conditional interactions were acquired for resistance to rice leaffolder. These loci were located on chromosomes 2, 9, 10, and 11, respectively. QTL pyramiding indicated that the positive alleles affect resistance to leaffolder. The prospective application of this data in rice breeding was also discussed.