Influence of the chickpea cropping system onHelicoverpa armigera (Lep.: noctuidae) populations and their rate of parasitism byCampoletis chlorideae (Hym.: ichneumonidae)

The effect of intercropping chickpea with coriander or linseed onHelicoverpa armigera Hübner egg and larval populations and on the rate of larval parasitism was examined. There were significantly moreH. armigera larvae per plot in the sole chickpea treatment than in the intercropped treatments. The reduction was not the result of a negative effect of the companion crops on the numbers of larvae attacking chickpea. Larval density on chickpea was higher in the intercropped plots than the plots of sole chickpea. The presence of the flowering companion crops did not result in either the attraction of otherwise uncommon parasitoids to the crop or an increase in the proportion ofH. armigera larvae parasitized byCampoletis chlorideae Uchida. The results suggest that chickpea is a more suitable host forH. armigera than coriander or linseed, and that the reduction in the density ofH. armigera larvae in the intercroped treatments was due to the lower number of chickpea plants in these treatments.