Grain yield response and Chilo partellus infestation in diverse sorghum-cowpea intercrop arrangements

Abstract

Yield improvement and insect pest control in intercropping systems relative to sole cultures has been variable and inconsistent over habitats, component species, varieties, density, row arrangement, soil fertility and moisture. This study was initiated to quantify yield response of two sorghum varieties (Macia and SV-2) and a cowpea variety, PAN311 to different crop arrangements and to assess the level of Chilo partellus infestation in sorghum in the intercropping system. Superior intercropped sorghum yield was obtained when component crops were arranged in alternate rows at a 0.90 m spacing whereas cow- pea yields were similar to or lower than sole crop yield in the different component crop arrangements. The overall land use efficiency, assessed by the land equivalent ratio (LER), was improved by an average of 11% with intercropping at a row spacing of 0.90 m. However, no yield benefit was observed when crops were arranged in an alternate row pattern at a narrow row spacing of 0.45 m. Intercropping reduced C. partellus infestation in mixed and alternate intercropping systems, relative to the sole cultures.