Morphological Variation in the Wild-Weedy Complex ofSorghum bicolorIn Situ in Western Kenya: Preliminary Evidence of Crop-to-Wild Gene Flow? uri icon

abstract

  • Crop wild relatives are important components of agroecosystems and have over the years been exploited inbreeding programs as sources of genes for novel traits. Information on the extent and patterns of variability isimportant in formulating effective conservation and utilization strategies for existing crop wild relativepopulations. We conducted surveys and collections of wild and weedy accessions of Sorghum bicolor(L.) Moench in Lambwe Valley in western Kenya in order to investigate occurrence, distribution, andmorphological variability in the wild-weedy complex of S. bicolor under local agroecological conditions. Wealso attempted to understand the role, if any, of crop-to-wild gene flow in structuring variability within andamong populations. The morphological data presented here showed wide variability within wild-weedysorghum populations with respect to habitats and morphotypes. True wild sorghum populations in nationalparks and the sugarcane belt were clearly distinguishable from the putative hybrids or intermediate formsfound in sorghum fields, in sorghum field margins, and, to some extent, by the roadside near sorghum fields.The existence of these intermediate forms is empirical evidence of introgression between cultivated sorghumand its wild-weedy relatives. Extensive introgression, especially within in situ conservation areas and/or inareas of high diversity, would lead to genetic erosion and possible depletion of these important wild sorghumgenetic resources

publication date

  • 2012