title: Genetic structure and mating system of wild cowpea populations in West Africa.
abstract: BACKGROUND
  Cowpea is a highly inbred crop. It is part of a crop-weed complex, whose origin and dynamics is unknown, which is distributed across the African continent. This study examined outcrossing rates and genetic structures in 35 wild cowpea (Vigna unguiculata ssp. unguiculata var. spontanea) populations from West Africa, using 21 isozyme loci, 9 of them showing polymorphism.
  
  
  RESULTS
  Outcrossing rates ranged from 1% to 9.5% (mean 3.4%), which classifies the wild cowpea breeding system as primarily selfing, though rare outcrossing events were detected in each population studied. Furthermore, the analyses of both the genetic structure of populations and the relationships between the wild and domesticated groups suggest possibilities of gene flow that are corroborated by field observations.
  
  
  CONCLUSIONS
  As expected in a predominantly inbred breeding system, wild cowpea shows high levels of genetic differentiation and low levels of genetic diversity within populations. Gene flow from domesticated to wild cowpea does occur, although the lack of strong genetic swamping and modified seed morphology in the wild populations suggest that these introgressions should be rare.
authors: International Centre of Insect Physiology and Ecology, Nairobi, Kenya.
authors: Eric B
authors: EB
authors: Kouam
authors: Remy S
authors: RS
authors: Pasquet
authors: Pascal
authors: P
authors: Campagne
authors: Jean-Baptiste
authors: JB
authors: Tignegre
authors: Kevin
authors: K
authors: Thoen
authors: Remi
authors: R
authors: Gaudin
authors: Jeremy T
authors: JT
authors: Ouedraogo
authors: Abdulai B
authors: AB
authors: Salifu
authors: Geoffrey M
authors: GM
authors: Muluvi
authors: Paul
authors: P
authors: Gepts
mesh_terms: D000354:Africa, Western; D003433:Crosses, Genetic; D007887:Fabaceae / Q000235:genetics*; D051456:Gene Flow; D040342:Genetic Structures / Q000235:genetics*; D014644:Genetic Variation; D005828:Genetics, Population; D005838:Genotype; D007178:Inbreeding