Title : Microsatellites facilitated investigation of quantitative trait loci for TLB resistance in maize
Turcicum leaf blight (TLB) incited by Exserohilum turcicum is a most persistent and destructive foliar disease of maize in a range of countries, including India. In Indian scenario, the states of Karnataka, Himachal Pradesh, Uttar Pradesh, Uttarakhand, Orissa, and Andhra Pradesh are the most affected by TLB disease. It causes substantial reductions in grain yield due to epiphytotics, these losses can range from 25% to 90%, depending on the severity of the disease. With the help of two mapping populations, F2:3 families and F2:6 families (RILs, Recombinant Inbred Lines), in two different environments, E1 (Varanasi, Uttar Pradesh, India; 250N, 830E) and E2 (Nagenahalli, Karnataka, India; 120N, 760E) under artificial epiphytotic condition, this study attempts to identify quantitative trait loci (QTL) by using microsatellites. A total of 23 QTLs for maize TLB resistance were found. Eight of these QTLs were found in the F2:3 mapping population of the CM 212 x V 336 cross, while fifteen QTLs were found in the RILs of the CM 212 x CM 145 cross. In order to advance resistance breeding programmes, this work attempts to identify and map the novel QTLs for TLB resistance in maize.