A study to investigate the potential contribution of pigeonpea to soil fertility management in smallholder farming systems was initiated at Doimboshava and in Murewa Communal Area during the 1996/97 cropping season. Its main focus is on biological nitrogen fixation and pigeonpea residue management. A participatory rural appraisal was first conducted to investigate the current role of legumes in soil fertility management in the farming systems. Limited use of legumes was revealed and was attributed to unavailability of seed and over-emphasis on maize production. The population levels of pigeonpea-nodulating rhizobia in 21 different soils were determined. The rhizobial populations were low (1-121 cells/g soil), but there were indications of a rapid population build-up after one season of growing pigeonpea. Short, medium and long duration pigeonpeas were grown, and their residual effects on: a subsequent maize crop will be tested in the 1997/98 season. Pigeon and maize biomass yields were assessed during the 1996/97 cropping season. Both maize and pigeonpea biomass yields were greatly reduced due to waterlogging, but long duration pigeonpea showed better recovery. The pigoenpea biomass yields ranged from 30 kg/ha for short duration to 9200 kg/ha for long duration. Although pigeonpea performance proved promising on the relatively infertile soils, there is need to determine optimum plant populations. Utilization aspects of the crop also need attention.
Publication year
1998
Authors
Mapfumo P; Mpepereki S; Mafongoya P L
Language
English
Keywords
biological nitrogen fixation, biomass, cajanus cajan, plant population, small farms, soil fertility
Geographic
Zimbabwe
