Allelic loci in Peking soybean conditioning resistance to Heterodera alvcines races 3 & 5

摘要

Heterodera alvcines Ichinohe (SCN) is the most devastating soybean pest worldwide. Genetically controlled resistance to SCN was first identified in cv. Peking (Ross and Brim, 1957). Peking, a selection from P.I. 17852B, was found to be resistant to SCN Races 1, 3, and 5, additionally was also reported to be resistant to Race 6 (Rao-Arelli et al., 1992a). A recent study indicated that resistance in Peking to SCN Race 3 isolate is conditioned by a combination of 3 genes rhg_1, rhg_2. and Rhg_4. (Rao-Arelli et. al., 1992b). These loci in Peking and P.I. 90763 are found to be allelic to SCN Race 3 isolate and the progenies from the crosses involving resistant parents, Peking X P.I. 88788 and P.I. 90763 X P.I. 88788 segregated both in F_2 and F_3 generations (Rao-Arelli and Anand, 1988). Furthermore, P.I. 88788 conditioned resistance to SCN Race 3 isolate with a combination of two dominant and one recessive genes (Rao-Arelli el al., 1992b).