QTL Identif ication of Resistance to Head Smut in Maize

Head smut of maize ( Zea mays L1) caused by Sporisorium reiliana is an important fungal disease in China1 Development of varieties resistant to this disease is one of the effective approaches to control the disease1 In this study , we mapped and characterized quantitative trait Loci (QTL) conferring resistance to head smut1 A genetic linkage map with 84 SSR and 48 AFLP marker loci were constructed based on a maize ( Zea mays L1) population consisting of 191 F2 individuals from the cross Mo17×Huangzao 41 The linkage map spans maize genome 1 54219 cM with average interval of 1117 cM between adjacent markers1 The corresponding 184 F3 families (7 missed) were evaluated for head smut resistance with two replications in Gongzhuling , Jilin Province and Harbin , Heilongjiang Province under artificial inoculation with chlamydospore , respectively1 Quantitative trait loci ( QTL ) were detected using composite interval mapping1 In Gongzhuling , 5 putative QTL conferring resistance to head smut were detected on chromosomes 1 , 2 , 3 , 8 and 9 , respectively , accounting for 1010 % to 1613 % of the phenotypic variance1 In Harbin , 5 putative QTL for resistance to head smut were found on chromosomes 1 , 2 , 3 , 4 and 7 , respectively , accounting for 416 % to 1314 % of the phenotypic variance1 The QTL with high LR values could be consistently identified on chromosomes 2 and 3 over two environments , displaying over2dominant and additive effects , respectively1 These results provided important information for germplasm improvement of heat smut resistance in maize1