title: The genetics of domestication of yardlong bean, Vigna unguiculata (L.) Walp. ssp. unguiculata cv.-gr. sesquipedalis.
abstract: OBJECTIVE
  The genetics of domestication of yardlong bean [Vigna unguiculata (L.) Walp. ssp. unguiculata cv.-gr. sesquipedalis] is of particular interest because the genome of this legume has experienced divergent domestication. Initially, cowpea was domesticated from wild cowpea in Africa; in Asia a vegetable form of cowpea, yardlong bean, subsequently evolved from cowpea. Information on the genetics of domestication-related traits would be useful for yardlong bean and cowpea breeding programmes, as well as comparative genome study among members of the genus Vigna. The objectives of this study were to identify quantitative trait loci (QTLs) for domestication-related traits in yardlong bean and compare them with previously reported QTLs in closely related Vigna.
  
  
  METHODS
  Two linkage maps were developed from BC(1)F(1) and F(2) populations from the cross between yardlong bean (V. unguiculata ssp. unguiculata cv.-gr. sesquipedalis) accession JP81610 and wild cowpea (V. unguiculata ssp. unguiculata var. spontanea) accession TVnu457. Using these linkage maps, QTLs for 24 domestication-related traits were analysed and mapped. QTLs were detected for traits related to seed, pod, stem and leaf.
  
  
  RESULTS
  Most traits were controlled by between one and 11 QTLs. QTLs for domestication-related traits show co-location on several narrow genomic regions on almost all linkage groups (LGs), but especially on LGs 3, 7, 8 and 11. Major QTLs for sizes of seed, pod, stem and leaf were principally located on LG7. Pleiotropy or close linkage of genes for the traits is suggested in these chromosome regions.
  
  
  CONCLUSIONS
  This is the first report of QTLs for domestication-related traits in yardlong bean. The results provide a foundation for marker-assisted selection of domestication-related QTLs in yardlong bean and enhance understanding of domestication in the genus Vigna.
authors.affiliation: Program in Plant Breeding, Faculty of Agriculture at Kamphaeng Saen, Kasetsart University, Kamphaeng Saen, Nakhon Pathom 73140, Thailand.
authors.forename: Alisa
authors.initials: A
authors.lastname: Kongjaimun
authors.forename: Akito
authors.initials: A
authors.lastname: Kaga
authors.forename: Norihiko
authors.initials: N
authors.lastname: Tomooka
authors.forename: Prakit
authors.initials: P
authors.lastname: Somta
authors.forename: Duncan A
authors.initials: DA
authors.lastname: Vaughan
authors.forename: Peerasak
authors.initials: P
authors.lastname: Srinives
mesh_terms: D002874:Chromosome Mapping; D018556:Crops, Agricultural / Q000235:genetics*; D019143:Evolution, Molecular; D007887:Fabaceae / Q000235:genetics*; D014644:Genetic Variation; D018745:Genome, Plant; D040641:Quantitative Trait Loci; D013045:Species Specificity