Mulching of yam seed beds reduced soil temperature and improved emergence, time of emergence, yield per hill and the total yield of Dioscorea rotundata yams on a sandy soil in Western Nigeria. Comparison of mounds with ridged and flat seed beds showed that these different treatments had no significant effect on tuber yield. Planting about six -weeks before the onset of the rains and the use of mulch is indicated as a good technique to obtain high yield.

Nigeria has substantial economic potential in its agricultural sector. However, despite the importance of agriculture in terms of employment creation, its potential for contributing to economic growth is far from being fully exploited. The sector's importance fluctuates with any rise and fall in oil revenue and has remained stagnant over the past ten years. The contribution of the manufacturing sector to the GDP declined over the same period. Inappropriate macroeconomic and sector policies perpetuated ...