Abstract
Bambara groundnut (Vigna subterranea (L.) Verde. or Voandzeia subterranea (L.) Thouars.) is one of the most important food crops in Africa and other parts of the world. Although abundant genetic resources have been identified, genetic inheritance studies and varietal improvement could not be initiated due to unsuccessful hybridization. Since the attempts we made at applying the hybridization method proposed by Schenkel (2002) and Massawe et al. (2003) were not successful, we eventually developed a more efficient method. We report herewith a hybridization technique that yielded 23 F, seeds from 4 crosses of morphologically distinct parental lines, TVsu 11, TVsu 870, TVsu 1061 and a Thai local variety. Emasculation method and pollination time were found to be the two critical factors that affected seed set. Emasculation by petal cutting could be performed at any time between 3 to 10 PM. However, hybridization was achieved only when pollination was conducted during the one hour period after the initiation of pollen shedding, namely at around 2:30 to 3:30 AM in Thailand. More successful crosses were obtained when the development stage of the female plants corresponded to peduncle elongation. Successful hybridization was confirmed by growing out the F-1 seeds and observing their phenotypic hybrid traits.
