System productivity and yield of component crops as affected by intercropping maize and common bean varieties with distinct morphological characteristics
Selection of maize and legumes variety selection in Ethiopia target only sole cropping system without considering the relative performance of varieties of varying morphologies under maize/legume intercropping. The objective of this study was to assess the effects of intercropping maize and common bean varieties with different morphologies on yield and system productivity of maize/common bean intercropping system. The treatments consisted of factorial combinations of three maize (BH543, BH661 and Gibe-2) and three common bean (Anger, Nassier and Haramaya) varieties and sole crops of the six varieties, which were laid out in randomized complete block design with three replications. The experiment was conducted at Bako, western Ethiopia, during the main cropping seasons of 2011 and 2012. Main effects due to variety and cropping system were significant for maize biomass and grain yield in both years. Relative to sole cropping system, intercropping significantly reduced maize and common bean grain yields by 7% and 70%, respectively. Intercropping increased plant height of common bean by 48% relative to sole crop conditions. Among the different intercropping combinations, growing common bean variety, Haramaya with maize hybrid BH661 gave the highest land equivalent ratio of 1.28, highest relative crowding coefficient of 6.75 and highest net benefit of Birr 23,328 ha-1. As a strategy to maximize land productivity and resource use efficiency, intercropping that involves the two compatible varieties of the component crops is recommended for Bako and similar areas of western Ethiopia.