Evaluation of six plant extracts for their possible repellent effects against lesser mealworm, Alphitobius diaperinus (Panzer)

Experiment was carried out to investigate the repellent effect of leaf and seed extracts of six indigenous plants namely dholkalmi, Ipomoea fistulosa; dutura, Datura fastuosa; eucalyptus, Eucalyptus citriodora; hatisur, Helitropium indicum; khetpapri, Hedyotis corymbosa and urmoi, Sapium indicum against lesser mealworm, Alphitobius diaperinus (Panzer). Leaf and seed extracts of the test plants had moderate repellent effect. Among the extracts, the highest repellency was observed in dholkalmi leaf extract (repellency 47.91%) and hatisur seed extract (repellency 47.47%). The ethanol extracts of leaf and water extracts of seed were more effective in repelling the pest than those of the other two solvent extracts. In most of the cases, repellency rate decreased with the progress of time and increased proportionally with doses. The results indicated the possibility of using dholkalmi leaf extract and hatisur seed extract as an alternative control measures for lesser mealworm as they were found to possess high repellency effect against the pes