INSECTICIDAL EVALUATION OF ANISALDEHYDE AGAINST Rhyzopertha dominica [COLEOPTERA: BOSTRYCHIDAE] INFESTING STORED WHEAT GRAINS (Triticum aestivum)

Abstract

The study investigates the insecticidal potential of Anisaldehyde against the survival of R. dominica infesting wheat grain under laboratory condition. The study was conducted in the research laboratory of Crop, Soil and Pest Management, The Federal University of Technology Akure, Nigeria. The compound was tested at 10, 20, 30, 40 and 50 µl /20g of wheat with 3 replicate each. Adult mortality of the insect was recorded at 24 h for 4 days, adult emergence, % inhibition rate and weight loss was observed. The mode of action of Anisaldehyde using neurotransmitter and digestive enzymes were also observed. It was observed that 50 µl dosage was the most effective among the treatments as it recorded 93.33% insect mortality within 24 h post-treatment and the effect was significantly (p < 0.05) different from other treatments. Only 40 and 50 µl of the compound were able to achieve 100% mortality but their effects were not significantly (p > 0.05) different from 30 µl dosage that recorded 86.67% insect mortality. The result obtained showed that 1.14 and 5.27 µl dosages of the compound are respectively required to achieve 50 and 95 % mortality of the insect at 72 h post-treatment. Both 40 and 50 µl dosage were able to cause 0% adult emergence, 100% inhibition rate and lead to no weight-loss. The 50 µl dose totally inhibited the activity of Acetylcholinesterase while a significant difference exists between the activity of lipase and others. It was evident from all observations that Anisaldehyde compound was effective. The findings also suggested that having displayed a promising insecticidal potential, it can be used as alternatives to synthetic chemical insecticides for the control of stored product insects as a whole.