title: DNA markers linked to Pga1, an adzuki bean gene that confers resistance to Cadophora gregata race 1.
abstract: Brown stem rot (BSR) caused by Cadophora gregata f. sp. adzukicola (syn. Phialophora gregata) is a serious soilborne disease of adzuki bean (Vigna angularis) in Japan. Cultivation of resistant cultivars is the most effective disease control method, therefore the selection of resistant lines is a priority for breeders. BSR-resistant adzuki bean lines have been screened in pathogen-infected fields. However, field selection using the pathogen and artificial inoculation methods is time-consuming and labor-intensive. In the present study, we used 105 F3 lines derived from a cross between a BSR-resistant cultivar 'Syumari' and a susceptible cultivar 'Buchishoryukei-1' for BSR inoculation tests. Amplified fragment-length polymorphism (AFLP) analyses with 1024 primer sets revealed that six fragments were polymorphic between resistance and susceptible bulked groups. Five DNA markers (Pg77, Pg118, Pg138, Pg139 and Pg126) were developed from the nucleotide sequences of polymorphic AFLP markers and their flanking regions. Pg118, which was derived from E-ACT/M-ACT-118, was tightly linked to the resistance gene Pga1 and was converted into a codominant marker for its easier use in marker-assisted selection for adzuki bean BSR resistance. Finally, the applicability of the developed markers for BSR resistance was tested on 32 adzuki bean accessions or cultivars.
authors.affiliation: Laboratory of Plant Pathology, Graduate School of Agriculture, Hokkaido University , Sapporo, Hokkaido 060-8589 , Japan ; Hokkaido Research Organization, Agricultural Research Department, Chuo Agricultural Experiment Station , Higashi-6, Kita-15, Naganuma, Hokkaido 069-1395 , Japan.
authors.forename: Takako
authors.initials: T
authors.lastname: Suzuki
authors.forename: Takamitsu
authors.initials: T
authors.lastname: Yoshii
authors.forename: Shohei
authors.initials: S
authors.lastname: Fujita
authors.forename: Hisanori
authors.initials: H
authors.lastname: Shimada
authors.forename: Toru
authors.initials: T
authors.lastname: Takeuchi
authors.forename: Norio
authors.initials: N
authors.lastname: Kondo
keywords: Cadophora gregata; DNA marker; adzuki bean; brown stem rot; resistance gene