Identification of SSR markers linked to the Phytophthora resistance gene Rps1‐d in soybean

Abstract

To identify markers for the Phytophthora resistance gene, Rps1-d, 123 F 2 : 3 families were produced from a cross between Glycine max (L.) Merr. ÔTanbakuroÕ (a Japanese traditional black soybean) and PI103091 (Rps1-d) as an experimental population. The results of virulence tests produced 33 homozygous resistant, 61 segregating and 29 homozygous susceptible F 2 : 3 families. The chi-squared test gave a goodness-of-fit for the expected ratio of 1 : 2 : 1 for resistant, segregating and susceptible traits, suggesting that the inheritance of Rps1-d is controlled by a monogenic dominant gene. Simple sequence repeat (SSR) analyses of this trait were carried out using the cultivars ÔTanbakuroÕ and PI103091. Sixteen SSR primers, which produced 19 polymorphic fragments between the two parents, were identified from 41 SSR primers in MLG N. Eight SSR markers were related to Rps1-d, based on 32 of the 123 F 2 : 3 families, consisting of 16 homozygous resistant and 16 homozygous susceptible lines. The remaining 91 families were analysed for these eight markers, and a linkage map was constructed using all 123 F 2 : 3 families. The length of this linkage group is 44.0 cM. The closest markers, Sat_186 and Satt152, are mapped at 5.7 cM and 11.5 cM, respectively, on either side of the Rps1-d gene. Three-way contingency table analysis indicates that dualmarker-assisted selection using these two flanking markers would be efficient.

Molecular mapping of two genes conferring resistance to Phytophthora sojae in a soybean landrace PI 567139B

“…On the short arm of chromosome 3, previously identified Rps genes, Rps1 and 7, have been mapped (Fig. 1a, f, g) (Anderson and Buzzell 1992;Demirbas et al 2001;Gardner et al 2001;Sugimoto et al 2008;Weng et al 2001). Rps1-a, 1-b, 1-c, 1-d and 1-k are believed to be different alleles of Rps1.…”

“…Whole genome sequencing identified a cluster of more than 30 NBS-LRR genes in a 6 Mb region between Satt159 and Chr. 03 Sugimoto et al (2008). h Linkage map of Rps9 reported by Wu et al (2011).…”

Genetic analysis and identification of DNA markers linked to a novel Phytophthora sojae resistance gene in the Japanese soybean cultivar Waseshiroge

“…The pathotypes of the 12 isolates were determined using the agar medium inoculation method described by Sugimoto et al (2006Sugimoto et al ( , 2008a, which is a modification of the hypocotyl inoculation method of Laviolette and Athow (1981). Seedlings were evaluated for resistant or susceptible reactions according to the method of Sugimoto et al (2006Sugimoto et al ( , 2008a. Briefly, after the first primary leaf appeared on a plant, the stem near ground level was covered with two 3-mmdiameter plugs of 20-day-old mycelium cultured on LBA (lima bean agar).…”

“…These lines were obtained from Dr. R. Nelson of the USDA-ARS in Urbana, Illinois, U.S.A. Tanbakuro and Williams (rps) were used as susceptible control plants during the virulence tests. The pathotypes of the 12 isolates were determined using the agar medium inoculation method described by Sugimoto et al (2006Sugimoto et al ( , 2008a, which is a modification of the hypocotyl inoculation method of Laviolette and Athow (1981). Seedlings were evaluated for resistant or susceptible reactions according to the method of Sugimoto et al (2006Sugimoto et al ( , 2008a.…”

“…Tsuchiya et al (1990) had also reported that Waseshiroge was highly resistant to many P. sojae isolates from Hokkaido and other locations in Japan. Simple sequence repeat (SSR) markers linked to Rps1d in PI103091 were identified by Sugimoto et al (2008a), and these markers have been used for MAS to breed new resistant cultivars adapted to Hyogo (e.g., an advanced breeding line 262-1-1). However, there have been no published reports on the presence of Rps gene(s) in Waseshiroge, despite its specific resistance.…”