Integration of Seed Dressing, Bio-pesticides and Intercropping to Reduce Pesticide Use in Snap Bean Production

Abstract

Insect pests remain a major constratint in the production of snap beans and farmers mainly rely on synthetic chemical pesticides to manage the insect pests and diseases. However, the introduction of maximum residue levels (MRLs) for export vegetables by European markets pose a challenge to the use of pesticides. This study developed sustainable options of managing snap bean pests and reducing chemical residues on snap bean produce. Field experiments were carried out for two planting cycles and evaluated the efficacy of seed dressing, sprays with neem, pyrethrin or biological product and intercropping with maize either alone or in combination. The data collected included population of whitefly, thrips and bean fly; yield and pest damage. The use of seed dressing in combination with two pyrethrin sprays and neem applied at the vegetative stage, early flowering and early pod growth stage reduced bean stem maggot, white fly and thrips population by up to 71%. This was comparable to the use of seed dressing combined with intercropping with maize plus three pyrethrin sprays at the vegetative stage, early flowering and early pod growth stage. The two options also reduced pod damage due to thrips by up to 87% and increased yield by up to 189%. The results demonstrated that integrated pest management options would be viable alternatives to synthetic chemical pesticides and this would enable snap bean farmers produce within acceptable residue limits.