Biodiversity on-farm in semi-arid agriculture: a case study from a smallholder farming system in Zimbabwe
An observational survey of standing crop characteristics was conducted in farmers' fields in Musikavanhu communal area of Zimbabwe, during the 1995/1996 cropping season, to investigate sorghum diversity and its role in household food security in semi-arid agriculture. The study revealed a wide diversity of crops growing in farmers' fields, often in a mixture. The major crop was sorghum, grown by 94% of the farmers and occupying 82% of the land. Eleven sorghum varieties were grown in the area during the surveyed season. Five extra varieties of sorghum were mentioned by farmers, but were no longer grown because seed became extinct. Cowpeas, pumpkins, cucumbers and watermelons were often intercropped with sorghum. These 'minor' crops are very important to farmers and are eaten as supplementary food, somewhat like vegetables or desserts. This enormous diversity of crop plants fulfils livelihood and nutritional needs. The use of cowpeas is an important aspect of many multiple-cropping systems and is particularly relevant to the development of low-external-input and sustainable agriculture systems. There is a definite need for national agricultural research systems (NARS) to capture this biodiversity by collecting samples for conservation and also to use this as the basis for improving production system in the area. Both in situ and ex situ conservation are essential and the links between them need to be improved.
The Zimbabwe Science News Volume 34(1) March 2001, pp. 13-18