LINKAGE ANALYSIS OF ER-1, A RECESSIVE PISUM-SATIVUM GENE FOR RESISTANCE TO POWDERY MILDEW FUNGUS (ERYSIPHE-PISI DC)

Linkage analysis was used to determine the genetic map location of er- 1, a recessive gene conditioning resistance to powdery mildew, on the Pisum sativum genome. Genetic linkage was demonstrated between er-1 an d linkage group 6 markers after analyzing the progeny of two crosses, an F-2 population and a set of recombinant inbred lines. The classes o f genetic markers surrounding er-1 include RFLP, RAPD and allozyme mar kers as well as the morphological marker Gty. A RAPD marker tightly li nked to er-1 was identified by bulked segregant analysis. After DNA se quence characterization, specific PCR primers were designed to convert this RAPD marker into a sequence characterized amplified region (SCAR ).