Peer review

African agriculture faces an unprecedented challenge to ensure food and nutrition security while adapting to climate change and coping with land fragmentation due to population growth. This study assessed the performance of sole cereal (maize, sorghum, millet) and cereal-legume intercropping systems in terms of grain, energy and protein yield, determining the land requirements for energy and protein self-sufficiency at the household level. On-farm trials were established in two districts of Malawi (Dedza and Mzimba) to test twelve cropping systems on 72 farms for three consecutive cropping seasons, resulting in 2,530 yield records. The results revealed that crop yields were much higher in Dedza than in Mzimba, reflecting the better agro-ecological potential in the former. Sole maize yielded 2.8 t ha−1 in Dedza while sole sorghum yielded 1.6 t ha−1 and sole millet yielded 1.7 t ha−1, and in Mzimba, sole maize yielded 2.0 t ha−1, with sorghum and millet yielding 0.9 t ha−1and 0.7 t ha−1, respectively. Across both districts, maize-legume intercrops yielded an average cereal component of 1.7–2.4 t ha⁻1. In comparison, sorghum-legume intercrops produced lower cereal yields ranging from 0.7 to 1.2 t ha⁻1, while millet-legume intercrops ranged from 0.6 to 1.4 t ha⁻1. Yet, the cereal-legume intercrops provided higher nutritional yields than sole cereals. Thus in Dedza, maize-legume intercrops met energy and protein nutritional security needs (based on annual requirements for 5 adults) for 87–96% of the farms, thereby enabling land sparing of 0.83–0.94 ha farm−1. Similarly, in Mzimba, maize-legume intercrops enabled farmers to meet energy and protein requirements for 70–88% of farms, thereby sparing 0.61–0.71 ha of land farm−1. At both sites, sorghum- and millet-legume intercrops were less effective than maize-legume intercrops. Therefore, maize cropping systems, particularly when intercropped with legumes, are the most viable option for achieving food and nutrition security in land-constrained settings and in agro-ecological environments similar to Dedza and Mzimba. Meeting energy and protein requirements with small grains remains challenging in densely populated areas with small farm sizes, as these crops yield far less than maize, hence the commonly observed preference for maize by farmers. Caution is advised for research and development programs targeting small grains in Malawi’s smallholder settings, as this may compromise energy and protein outputs at the farm level.

Text in English

European Union (EU)