Deterrent Susceptibility of Ethanolic and Methanolic Leaf Extracts of Strychnos spinosa (Loganiaceae) Plant Against Cowpea Weevil (Callosobruchus maculatus)

Abstract

This study tested the cowpea-repelling potential of Strychnos spinosa. To achieve this aim, an experiment was conducted by infesting the cowpea seeds with the adults of Callosobruchus maculatus with different dosages of the plant extracts (0. 2g, 0.4g, and 0.6g) in order to assess their effect on the rate of mortality and eggs laid by insects. The experiment was done in order to determine the effectiveness of methanolic and ethanolic extracts from the plant's leaves to manage Callosobruchus maculatus. According to the study, both ethanolic and methanolic extracts had an impact on adult insects after 72 hours when compared to the positive control. Furthermore, it was discovered that when compared to methanolic leaf extract of the plant, ethanolic leaf extract of the plant creates a substantial influence on the mortality of Callosobruchus maculatus following exposure to the environment for 72 hours. However, as the dosage for either of the two extracts is increased, the subject insect's egg production drops. The results show that 0.4g of the plant's ethanolic extract could be utilized as a control material to produce a significant level of protection on stored cowpea seed against cowpea-related damage.