No abstract

No abstract

Falling world grain stocks, rising grain prices and the poor economic situation of Africa have, since 1995, made food security a major issue. Structural adjustment programmes, the crushing burden of debt, the collapse of commodity prices and mismanagement of national economies have rendered African people even poorer in terms of per capita income and quality of life than they were in the first decade after the attainment of independence. Yet Africa is rich in many ways — for example, in virgin land for agriculture and in mineral resources, including energy. It is rich above all in its people and their determined spirit to face all disasters, natural and man-made. In line with this spirit, Africa is moving ahead on a new consensus that food security through enhanced agricultural production is the continent's most fundamental development issue. Although the economic plans of successive African governments have stressed the goal of food self-sufficiency, the food sector has received little investment or political priority. Africa continues to rely on food aid and food imports, which consume a large part of its meagre export earnings. The increasingly limited capacity to purchase food abroad and the bitter experience of depending on emergency aid are honing a clear determination that Africa must marshal the resources to grow its own food and so release the creative energies of its people to contribute fully to their own development and well-being. Top priority should be given to food security during this process, as no country can consider itself free until it has the wherewithal to provide for the basic needs of its people.

No abstract

SUMMARYOver a decade after the forest-savanna transition zone of Nigeria was deemed suitable for production of sorghum (Sorghum bicolor), no research has been undertaken on the crop's tillage requirements in the southeastern part of the zone. This study evaluated the effects of tillage-mulch practices on soil moisture, water use (WU), grain yield and water use efficiency (WUE) of the crop in a Typic Paleustult (sandy loam) at Nsukka during 2006 and 2007 growing seasons. In a split-plot design, no-till (NT) and conventional tillage (CT) treatments were left bare (B) or covered with mulch (M) at 5 Mg ha−1. The ensuing treatments (NTB, NTM, CTB, and CTM) represented four tillage methods, which were replicated four times in a randomized complete block. In the monitored root zone, NTB and CTM significantly (p ≤ 0.05) enhanced the soil moisture status over NTM and CTB, but the main effects of the tillage and the mulch factors were not significant. The crop WU was uninfluenced by the treatments throughout the study. Although the grain yield showed higher values with NT than with CT, the differences were significant (p ≤ 0.05) only in 2007 that was marked with erratic rainfall and relatively low mean yield. Mulch significantly (p ≤ 0.05) enhanced the grain yield in 2006, with greater effect in CT than NT. On average, the mulch plots out-yielded their bare counterparts by about 26%. The tillage × mulch interaction was significant (p ≤ 0.01), and showed higher grain yields in NTB, NTM and CTM than in CTB. In the year-weighted average, yield increments in NTB, NTM and CTM over CTB were 53, 53 and 67% respectively, a pointer to the relevance of mulch with the CT but not the NT. Relative WU showed that the crop's water demand was met under all treatments. Hence, the yield reduction in the CTB was not due to water shortage. The WUE varied among the treatments in the same pattern as grain yield. In summary, NTB and CTM proved superior to NTM only in soil moisture status but to CTB in all measured parameters. From a socio-economic viewpoint, however, NTB would be preferable to CTM for growing sorghum in this area.