Pesticidal Potential of Selected Aqueous Plant Extracts for the Control of Leaf Caterpillar (Hymenia recurvalis Fab.) Infestation on Amaranth (Amaranthus spp) in Kashere, Gombe State Nigeria

Abstract

The amaranth leaf webber caterpillar (Hymenia recurvalis Fab.) is a serious pest of amaranth that cause serious leaf damage to amaranth through perforation of its leaves and stem thereby reducing its growth and yield. The insect is a major limiting factor in amaranth production. Field experiments were conducted during 2022 and 2023 with the aim of assessing insecticidal potential of five selected plant leaf extracts, namely Moringa oleifera, Azadiractha indica  A. Juss , Balanites aegyptiaca Del., Momordica balsamina and Hyptis suaveolens using Lambda cyhalothrin 2.5 EC, a synthetic insecticide as a check. The experiment was conducted in a randomized complete block design (RCBD) replicated three times. Results showed that A. indica and H. suaveolous were more effective in reducing H. recurvalis population, leaf perforation, leaf damaged and improved amaranth plant growth and yield. This was closely followed by B. aegyptiaca and M. balsamina while M. oleifera had the lowest effect on the use of pest population and damage. Lambda cyhalothrin, a synthetic insecticide, was found to be superior to the five plant extracts. The result showed that A. indica and H. suaveolens improved the growth and yield of amaranth during the study period. It is recommended that A. indica and H. suaveolens could be used by resource- limited farmers to mitigate infestation and damage to amaranth by leaf webber caterpillar (H. recurvalis) in the study area.