Legume rotations improve fertility and help control witchweed. Validated RNRRS Output.


This is one of 280 summaries describing key outputs from the projects run by DFID's 10-year Renewable Natural Resources Research Strategy (RNRRS) programmes.

Principally based on Projects R6654, R8194 and R8436. Farmers in eastern and southern Africa could double their yields simply by growing legumes for a year in between cereal crops. Two problems that cause low yields are poor soil fertility and the rampant witchweed, Striga. Rising populations in rural areas mean that land is cropped more intensively. So farmers plant cereals—maize, upland rice, sorghum and finger millet—year after year, instead of leaving the land crop-free to recover and to help control witchweed. Villagers in Kyela, Morogoro and Mbeya in Tanzania now rotate cereals and legumes. They dig in the legumes as green manure. In rice-legume rotations, witchweed dropped by half. These rotations could have a major impact in the region, as many poor farmers cannot afford fertilizers or herbicides.

The CD has the following information for this output: Description, Validation, Current Situation, Current Promotion, Impacts On Poverty, Environmental Impact. Attached PDF (12 pp.) taken from the CD.


CPP66, New technologies, new processes, new policies: tried-and-tested and ready-to-use results from DFID-funded research, Research Into Use Programme, Aylesford, Kent, UK, ISBN 978-0-9552595-6-2, p 22.

Published 1 January 2007