Plant & Animal Genome VI Conference

P176

MOLECULAR MAPPING OF A GENE FOR RESISTANCE TO Septoria tritici BLOTCH IN WHEAT

1. USDA-ARS, Department of Botany and Plant Pathology, 1155 Lilly Hall, Purdue University, West Lafayette, IN 47907-1155
2. Department of Botany and Plant Pathology,1155 Lilly Hall, Purdue University, West Lafayette, IN 47907-1155

Septoria leaf blotch caused by Mycosphaerella graminicola (aka Septoria tritici) is an important disease of wheat. A population of recombinant inbred lines (RILs) was developed from a cross between the resistant line 72626E2-12-9-1 and the susceptible cultivar Arthur to analyze the inheritance of Septoria resistance and to identify molecular markers linked to the resistance gene. Genetic analysis of 106 RILs indicated that the resistance in line 72626E2-12-9-1 is controlled by a single dominant gene. Bulked segregant analysis of resistant and susceptible RILs was performed with amplified fragment length polymorphism (AFLP) analysis and simple sequence repeat (SSR) or microsatellite markers. Potentially linked AFLP and SSR markers identified from the bulked segregant analysis were scored on the complete RIL population to determine the linkage relationships. One AFLP marker was loosely linked to the resistance gene at a map distance of approximately 14 cM. A genetic map of the resistance gene will be constructed with additional AFLP and SSR markers using the complete population of recombinant inbred lines.