Cropping Systems with Groundnut: Resource Use and Productivity

In the rainfed semi-arid tropics (SA T) the relatively short gro wing season usually limits the choice \nof cropping systems with groundnut, either to solecrop or intempping systems. This paper \nexamines some of the mechanisms associated with environmental factors that can enable intercropping \nsystems to outyield sole-crop systems. Temporal intercropping systems, when the \ncomponent crops make their peak demands on resoums at different times, an illustrated with a \ngroundnut/pigeonpca system. In this system higher yields from intercropping am associatad with \na fuller use of environmental resoums over time. Spatial intemropping systems an illustr~ted \nwith a 3-year rainy-season study on millet/groundnut. A higher yield from intercropping was \nmost notably associated with impro vcd light-energy con version. Drought-stress studies on \nsorghum/groundnut and millet/groundnut showed no stress effkcts on the relative dry-matter \nyield advantages of intercropping, However, relative reproductive yield advantages of intercropping \nincreased markedly with stress because the harvest index of sorghum and groundnut \ndecreased much less in intemropping than in sole cropping. The importance of nitrogen fixrtion \nin intercropped groundnut and the likely benefits to nonlegume companions or following crops \nrue also discussed.