Identification of QTL for Banded Leaf and Sheath Blight in Teosinte-Derived Maize Population

Banded leaf and sheath blight is considered as the most important disease of maize, and development of resistant varieties is the most viable option. Total one seventy-one [169 BC 1 F 5 teosinte-derived maize lines along with teosinte (resistant) and DI-103 (susceptible) as a check] were planted in randomized complete block design in two different dates of sowing (DE 1 and DE 2 ) under artificially inoculated environments. Molecular profiling of population was carried out with identified 76 polymorphic microsatellite markers. Association of the markers with the quantitative trait loci (QTL) was performed by single marker analysis (SMA) using linear regression and maximum likelihood analysis. The single marker analysis of variance (ANOVA) revealed one major QTL on chromosome 5 and four minor QTLs on chromosomes 1, 3, 4, and 8, respectively, for BLSB resistance under first sowing (DE 1 ). In second sowing (DE 2 ), four minor QTLs were detected on four chromosomes 1, 3, 5 and 8. Out of these, nine QTLs two were identified across the environments, which were linked with markers umc1500 and phi10918 , considered as stable QTLs. Among seven detected QTLs for BLSB resistance, a major QTL linked with phi10918 was co-localized with three minor QTLs for ear length, kernel rows per ear and kernels per row. These results suggest that the morphological traits and QTLs which have been found to associate with banded leaf and sheath blight resistance are a good choice to enhance BLSB resistance. Utilization of QTLs governing morphological traits like days to anthesis, days to silking, flag leaf architecture, plant height, etc., could be a good choice along with QTLs governing BLSB resistance to enhance BLSB resistance through QTL pyramiding.