The effect of non-crop vegetation on the insect pests and their natural enemies in cashew (Anacardium occidentale L.) plantations

R.K. Peng, K. Christian and K. Gibb, Faculty of Science, Northern Territory University, Darwin, Northern Territory 0909, Australia.


In order to introduce an integrated pest management program in cashews, the effect of non-crop vegetation on the arthropod fauna in cashew plantations in tropical northern Australia was studied by taking regular vacuum samples. Where cashews had rich understorey and were closely surrounded by non-crop vegetation, the diversity of arthropods, the ratio of the total natural enemy numbers to insect pests and the average yield were significantly higher than where cashew trees had no understorey and were isolated from non-crop vegetation. We suggest that the close proximity of non-crop vegetation enriches the diversity of arthopods in cashew plantations by providing a reservoir of natural enemies that naturally regulate insect pests and results in an increased crop yield.


Plant Protection Quarterly (1998) 13 (1) 16-20.