Entomo-toxicity potentials of Guinea Henweed (<i>Petiveria alliacea</i>) and Sponge gourd (<i>Luffa cylindrica</i>) crude aqueous extracts compared with synthetic insecticide against <i>Podagrica</i> spp (coleoptera: chrysomalidae) infestation on okra

Abstract

Entomo-toxicity potentials of Guinea Henweed (Petiveria alliacea) and Sponge gourd (Luffa cylindrica) crude aqueous extracts against insect infestation on okra (Abelmoschus esculentus) were evaluated during the early and late cropping seasons of 2016 at the Teaching, Research and Commercial Farms, Rufus Giwa Polytechnic, Owo, Ondo State, Nigeria. The experiment was laid out in a Randomized Complete Block Design (RCBD) in three replicates, with extracts prepared at a concentration of 20% w/v. The crude extracts had significant decrease effects on the population of Podagrica beetle. Plots treated with the synthetic insecticide and P. alliacea aqueous extracts at 3 and 7 days after first and second spraying reduced the beetle population compared to pre-spraying state. However, there was no significant difference (P>0.05) between the two aqueous extracts except at 7 days after first and second sprays for both early and late cropping seasons. However, there exist significant difference (P<0.05) among the various treatments 3 and 7 DAS after fourth spray. P. alliacea aqueous extracts gave good protection to the okra plants so much that there was no significant difference (P>0.05) in resultant yield attributes compared to the synthetic insecticide as it was able to significantly suppress damage caused to okra plant leaves by the target insect. The results from this study show that crude P. alliacea aqueous extracts could be adopted by resource poor farmers as an alternative to synthetic insecticides in controlling Podagrica spp infestation on okra plot. However, further study is required to know the bioactive chemical constituents responsible for the plant insecticidal properties.