title: The genetic diversity of the Vigna angularis complex in Asia.
abstract: A selected set of accessions of components of the azuki bean (Vigna angularis) complex comprising 123 cultivated accessions and 23 wild or weedy accessions from Bhutan, China (including Taiwan), India, Japan, Korea, and Nepal was analyzed using amplified fragment length polymorphism (AFLP) methodology. Using 12 AFLP primer pairs, 580 unambiguous bands were generated, 313 (53.9%) of which were polymorphic among azuki bean accessions. All 580 bands were used to assess phenotypic (band) and genetic (nucleotide) diversity among the 146 azuki bean accessions. The results indicate five major groups of azuki bean germplasm primarily associated with geographic origin of accessions and their status: wild, weedy, or cultivated. These five groups are (i) Himalayan wild, (ii) Nepal-Bhutan cultivated, (iii) Chinese wild, (iv) Taiwan wild - Bhutan cultivated, and (v) northeast Asian accessions. Within the northeast Asian accessions, three subgroups are present. These consist of (v1) Japanese complex - Korean cultivated, (v2) Japanese cultivated, and (v3) Chinese cultivated accessions. The results suggest domestication of azuki bean occurred at least twice, once in the Himalayan region of southern Asia and once in northeast Asia. The remarkable diversity of azuki bean germplasm in the Himalayan region compared with other regions suggests this is a rich source of germplasm for plant breeding. The results suggest there are important gaps in the germplasm collections of azuki bean and its close relatives from various parts of Asia and that specific collecting missions for Vigna germplasm related to azuki bean in the highlands of subtropical Asia are needed.
authors.affiliation: Institute of Crop Germplasm Resources, Chinese Academy of Agricultural Sciences, Beijing, China.
authors.forename: Xu Xiao
authors.initials: XX
authors.lastname: Zong
authors.forename: Akito
authors.initials: A
authors.lastname: Kaga
authors.forename: Norihiko
authors.initials: N
authors.lastname: Tomooka
authors.forename: Xin Wang
authors.initials: XW
authors.lastname: Wang
authors.forename: Ouk Kyu
authors.initials: OK
authors.lastname: Han
authors.forename: Duncan
authors.initials: D
authors.lastname: Vaughan
mesh_terms: D000704:Analysis of Variance; D007887:Fabaceae / Q000235:genetics*; D005819:Genetic Markers; D014644:Genetic Variation; D010802:Phylogeny
chemical_list: D005819:Genetic Markers