Crop Growth, Development and Yield in Semi-arid Conditions in Botswana. II. The Effects of Intercropping <i>Sorghum Bicolor</i> with <i>Vigna Unguiculata</i>

Abstract

SUMMARY Plant growth, development and yield were monitored in sorghum/cowpea intercropping trials in Botswana during the drought seasons of 1982/3 and 1983/4. The cowpea proved to be more competitive than sorghum in these arid conditions, resulting in substantial increases in sorghum mortality and developmental delay, and substantial decreases in sorghum leaf area indices, dry weight production and grain yield. Intercropping in standard rows at medium plant densities resulted in Land Equivalent Ratios considerably less than 1.0, in contrast to earlier trials in Botswana in higher rainfall years which demonstrated intercropping advantages. Low density, wide row intercropping resulted in some small intercropping advantages, suggesting that this treatment may have potential in Botswana's variable climatic conditions.