A preliminary investigation of the potential for maize - legume intercropping in the semi-arid area of Sidamo region, Ethiopia. I. Maize response

An intercropping trial involving four legumes, three maize planting densities and two legume planting times was undertaken at Dembela Wacho in the Sidamo region of Ethiopia during the 1987 growing season. The objective was to explore the potential of intercropping maize (Zea mays) with legumes within the existing Borana cropping system. The legumes examined were cowpeas (Vigna unguiculata), lablab (Lablab purpureus), cassia (Cassia rotundifolia) and centro (Centrosema schottii). In an ‘average’ growing season for the area, maize grain yield decreased by about 30% when intercropped with both cowpeas and lablab. The effect of cassia and centro was not significant. Legume planting time showed a significant effect on maize grain yield only when the legumes were cowpeas and lablab. Maize grain yield increased by 43% and 36% for cowpeas and lablab respectively when planted 20 days after the maize was sown. Maize planting density had a significant effect on maize grain yield in that yield increased with increased plant population. However, the increase in grain yield was not proportional to the maize planting density. The dry matter yield followed the trend of the grain yield. These results showed that intercropping was more advantageous than sole cropping of maize. Delaying the planting time of cowpeas and lablab after that of maize is recommended, while cassia and centro could be planted together with maize. The best maize planting density under the given conditions was about 55 000 plants ha−1.