Performance of five bambara groundnut ( Vigna subterranea (L.) Verdc.) landraces in the trasition agroecology of Ghana under different sowing dates

Drought associated with climate change is a potential threat to agriculture and food security in many sub-Saharan African countries. The need to promote drought tolerant crop cultivars acceptable to consumers cannot be overemphasized. Bambara groundnut is an underutilized and until lately, under researched crop. Its ability to produce some yields where other crops such as groundnut fail has been established. The balanced nutritional quality of the crop coupled with its tolerance to drought makes it a crop of choice to achieve food security especially in the dry areas of Africa. With the threat of climate change and its attendance drought coupled with the drying up of water bodies even when irrigation facilities are available, research on crops with inherently drought tolerant characteristics cannot be overemphasized. Sowing dates have been identified to affect the yield of the crop. Experiments were conducted in 2007 in Wenchi in the Transition agroecology of Ghana to determine the effect of sowing dates on the yield of bambara groundnut landraces namely; Burkina, NAV 4, NAV Red, Black eye, Tom, Mottled Red and Ada. Sowings were done in a factorial arrangement in a randomized complete block design with three replications. Pod and seed yields ranged between 600 kg/ha to 5.5 t/ha and 420 kg/ha to 3.8 t/ha, respectively for the various sowing dates. Pod yield of over 5 t/ha was produced by Burkina and Black eye. Pod harvest indices ranged from 0.12-0.53. Minor rainy season sowing of bambara groundnut in Ghana produced more pod yield than major rainy season sowing as shown by the August sowing. Tom was a highly vegetative landrace. Where irrigation is available, sowing bambara groundnut just before the rains in February in the Transition agro-ecology of Ghana produce high pod yields. Crop growth rate was highest for NAV Red (0.089 t/ha/d) and least with Tom (0.059 t/ha/d). Keywords : Bambara groundnut, Transition agro-ecology, landraces, sowing date