title: Detection of genome donor species of neglected tetraploid crop Vigna reflexo-pilosa (créole bean), and genetic structure of diploid species based on newly developed EST-SSR markers from azuki bean (Vigna angularis).
abstract: Vigna reflexo-pilosa, which includes a neglected crop, is the only one tetraploid species in genus Vigna. The ancestral species that make up this allotetraploid species have not conclusively been identified, although previous studies suggested that a donor genome of V. reflexo-pilosa is V. trinervia. In this study, 1,429 azuki bean EST-SSR markers were developed of which 38 EST-SSR primer pairs that amplified one product in diploid species and two discrete products in tetraploid species were selected to analyze 268 accessions from eight taxa of seven Asian Vigna species including V. reflexo-pilosa var. glabra, V. reflexo-pilosa var. reflexo-pilosa, V. exilis, V. hirtella, V. minima, V. radiata var. sublobata, V. tenuicaulis and V. trinervia to identify genome donor of V. reflexo-pilosa. Since both diploid and tetraploid species were analyzed and each SSR primer pair detected two loci in the tetraploid species, we separated genomes of the tetraploid species into two different diploid types, viz. A and B. In total, 445 alleles were detected by 38 EST-SSR markers. The highest gene diversity was observed in V. hirtella. By assigning the discrete PCR products of V. reflexo-pilosa into two distinguished genomes, we were able to identify the two genome donor parents of créole bean. Phylogenetic and principal coordinate analyses suggested that V. hirtella is a species complex and may be composed of at least three distinct taxa. Both analyses also clearly demonstrated that V. trinervia and one taxon of V. hirtella are the genome donors of V. reflexo-pilosa. Gene diversity indicates that the evolution rate of EST-SSRs on genome B of créole bean might be faster than that on genome A. Species relationship among the Vigna species in relation to genetic data, morphology and geographical distribution are presented.
authors.affiliation: Program in Plant Breeding, Faculty of Agriculture at Kamphaeng Saen, Kasetsart University, Kamphaeng Saen, Nakhon Pathom, Thailand.
authors.forename: Sompong
authors.initials: S
authors.lastname: Chankaew
authors.affiliation: Genetic Resources Center, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan.
authors.forename: Takehisa
authors.initials: T
authors.lastname: Isemura
authors.affiliation: Kazusa DNA Research Institute, Kisarazu, Chiba, Japan.
authors.forename: Sachiko
authors.initials: S
authors.lastname: Isobe
authors.affiliation: Genetic Resources Center, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan.
authors.forename: Akito
authors.initials: A
authors.lastname: Kaga
authors.affiliation: Genetic Resources Center, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan.
authors.forename: Norihiko
authors.initials: N
authors.lastname: Tomooka
authors.affiliation: Department of Agronomy, Faculty of Agriculture at Kamphaeng Saen, Kasetsart University, Kamphaeng Saen, Nakhon Pathom, Thailand.
authors.forename: Prakit
authors.initials: P
authors.lastname: Somta
authors.affiliation: Kazusa DNA Research Institute, Kisarazu, Chiba, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Hirakawa
authors.affiliation: Kazusa DNA Research Institute, Kisarazu, Chiba, Japan.
authors.forename: Kenta
authors.initials: K
authors.lastname: Shirasawa
authors.affiliation: Genetic Resources Center, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan.
authors.forename: Duncan A
authors.initials: DA
authors.lastname: Vaughan
authors.affiliation: Department of Agronomy, Faculty of Agriculture at Kamphaeng Saen, Kasetsart University, Kamphaeng Saen, Nakhon Pathom, Thailand.
authors.forename: Peerasak
authors.initials: P
authors.lastname: Srinives
mesh_terms: D004171:Diploidy; D020224:Expressed Sequence Tags / Q000378:metabolism; D007887:Fabaceae / Q000235:genetics*; D005819:Genetic Markers; D018745:Genome, Plant; D057891:Tetraploidy
chemical_list: D005819:Genetic Markers