Conservation agriculture-based Zea mays (maize)-Phaseolus vulgaris (common bean) cropping systems in South Central Ethiopia

Conservation agriculture (CA) is defined as sustainable agriculture production system comprising a set of farming practices. The experiment was conducted at three districts from 2011 to 2016 at five farmers’ field they considered as replicate. The experiment consisted of five treatments (continuous sole maize, maize bean rotation, maize-bean inter-cropping, bean rotation under CA and farmer practice). Maize yield and yield related traits and soil water data were collected from each site. Soil moisture content under CA practices was higher than the farmer practice. At East-Badawacho and Meskan grain yield was higher by 4 and 8% in CA compared with farmer practice, respectively. Maize bean rotation and sole maize under CA out yielded the farmer practice by 13 and 4%, respectively but inter-cropping had 5% lower grain yield. At Hawassa-Zuriya, CA maize bean rotation had higher yield than farmer practice in 2011 and 2013. Maize-bean inter-cropping, maize bean rotation and sole maize under CA had 10, 8 and 6% higher grain yield than farmer practice, respectively. Common bean grain yield from bean rotation under CA had 2799, 2908, and 3226 kg ha-1, from inter cropping bean grain yield of 817, 1065 and 927 kg ha-1 obtained at East-Badawacho, Hawassa-Zuriya and Meskan districts, respectively. Generally, CA cropping systems had drought stress reduction potential and greater yields compared with farmer practice.   Key words: Farmer-practice, sole-maize, rotation, inter-cropping, rift-valley.