Abstract:

【Objective】 The aim of the study was to establish a set of differential strains to identify soybean resistance gene to Phytophthora root rot and then to apply it for analysis of the resistance genes Rps1a, Rps1c and Rps1k that soybean cultivars or lines may carry. 【Method】 Virulence formula of 125 P. sojae isolates were determined using the hypocotyls inoculation technique, the strains, which include 6 isolates with different virulence formulas, were applied to identify the resistance of 55 soybean cultivars (lines) and resistance gene, were analyzed using the gene postulating procedure. 【Result】 Eighteen reaction types occurred in 55 cultivars or lines and results of gene postulation indicated that 2 cultivars (lines) probably carried the gene Rps1c and no cultivar may carry the gene Rps1a or Rps1k. 【Conclusion】 A few of soybean cultivars (lines) from Huanghuai valley carry Rps genes Rps1a, Rps1c and Rps1k and tend to be infected by Phytophthora sojae, so resistant cultivars (lines) need to be bred and popularized actively.

Key words: Phytophthora sojae, differential strains, soybean, Phytophthora root rot, resistance gene