Fine Mapping, Candidate Gene Identification and Co-segregating Marker Development for the Phytophthora Root Rot Resistance Gene RpsYD25

Abstract

Phytophthora root rot (PRR) caused by Phytophthora sojae is a serious disease of soybean. The most effective disease-control strategy is to deploy resistant cultivars carrying Rps genes. Soybean cultivar Yudou25 can effectively resist pathotypes of P. sojae in China. Previous studies have mapped the Rps gene in Yudou25, RpsYD25, on chromosome 3. In this study, at first RpsYD25 was located between SSR markers Satt1k3 (2.2 cM) and BARCSOYSSR_03_0253 (4.5 cM) by using an F 2:3 population containing 165 families derived from Zaoshu18 and Yudou25. Then the recombination sites were identified in 1127 F 3:4 families derived from Zaoshu18 and Yudou25 using the developed PCR-based SNP, InDel and SSR markers, and RpsYD25 was finely mapped in the a 101.3 kb genomic region. In this region, a zinc ion binding and nucleic acid binding gene Glyma.03g034700 and two NBS-LRR genes Glyma.03g034800 and Glyma.03g034900 were predicted as candidate genes of RpsYD25, and five co-segregated SSR markers with RpsYD25 were identified and validated to be diagnostic markers. Combined with the resistance reaction to multiple P. sojae isolates, seven of 178 soybean genotypes were detected to contain RpsYD25 using the five co-segregated SSR markers. The soybean genotypes carrying RpsYD25 and the developed co-segregated markers can be effectively applied in the breeding for P. sojae resistance in China.

Progress and prospectus in genetics and genomics of Phytophthora root and stem rot resistance in soybean (Glycine max L.)

“…Sahoo et al (2017) also reported several NBS-LRR-like genes in genetic investigations of Rps12. Jiang et al (2020) and Zhong et al (2020) also reported NBS-LRR and zinc ion-binding genes as candidate genes by fine mapping of RpsYD25 and RpsGZ.…”

“… Zhong et al (2019) identified RpsX in soybean cultivar Xiu94-11; subsequently, it was revealed that RpsX was located in the 242-kb genomic region spanning the RpsQ locus on chromosome 3. Zhong et al (2020) fine-mapped RpsYD25 in 1127 F 3:4 families derived from “Zaoshu18” and “Yudou25;” subsequently, 7 out of 178 soybean genotypes containing RpsYD25 were identified using five co-segregated SSR markers. Recently, Jiang et al (2020) have fine-mapped RpsGZ to a 367.371-kb genomic region on chromosome 3 in recombinant inbred lines (RILs) derived from a cross of the resistant cultivar “Guizao1” and the susceptible cultivar “BRSMG68.” Sahoo et al (2017) identified Rps12 on chromosome 18 in an RIL population developed by crossing the P .…”

RXLR effector gene Avr3a from Phytophthora sojae is recognized by Rps8 in soybean

“…Controlled by a single gene, it is also easier to select phenotypes during breeding and facilitates their introgression into elite cultivars. Soybean is indeed a rich source of race‐specific resistance as nearly 30 Rps genes have been identified and mapped to nine chromosomes since the 1950s (Zhong et al, 2020). From this catalogue of genes, six have been successfully introgressed into commercial soybean varieties, namely Rps1a , Rps1b , Rps1c , Rps1k , Rps3a , and Rps6 (Abeysekara et al, 2016; Sugimoto et al, 2012).…”

Genome-Wide Association Study of Partial Resistance to P. sojae in Wild Soybeans from Heilongjiang Province, China

“…A novel Phytophthora resistance gene, RpsZS18 , was detected on chromosome 2 of the soybean cultivar Zaoshu18 [ 17 ]. RpsYD25 was predicted as a candidate gene and validated to be a diagnostic marker for P. sojae resistance breeding [ 18 ].…”