A Review and Perspective on Soybean (Glycine max L.) Breeding for the Resistance to Phytophthora sojae in Korea

Phytophthora root and stem rot (PRR) of soybean is a severe disease that causes significant economic losses in soybean-growing countries. The causal agent, Phytophthora sojae, is a soil-borne oomycete that causes pre- and post-emergence damping-off of soybean in poorly drained soils. PRR has not been a severe problem in South Korea; however, as the cultivation of soybean in paddy fields recently increased, there is a growing interest because the incidence of PRR can be extensively expanded. R-gene mediated resistance is known as the main strategy for the management of this disease. On the other hand, partial resistance has also been known to provide more effective disease management than the Rps (Resistance to Phytophthora sojae) resistance. Responses of domestic soybean cultivars to a few P. sojae isolates were recently reported, while phenotypic distribution of numerous germplasms is mostly unknown. The objectives of this review are to summarize published studies conducted on PRR, to suggest future directions of genetic researches and breeding to the target pathogen. This review will discuss the followings; i) a brief introduction to PRR and the causal agent P. sojae, ii) types of genetic resistance to P. sojae and findings of genes/QTL conditioning to resistance, iii) changes in virulence pathotype of P. sojae populations, and iv) current status and perspective of genetic/genomic researches on the interaction of soybean and P. sojae in the South Korea.