INSECTICIDAL EFFECTS OF SOME SELECTED PLANT EXTRACTS AGAINST FALL ARMYWORM (Spodoptera frugiperda J.E. SMITH)

Abstract

This study was conducted at the Crop and Soil Laboratory (N12 13’19.9” E008 13’03.1”), Department of Agricultural Education, Federal College of Education (Technical) Bichi, Kano State, to assess the efficacy of plant extracts and a synthetic insecticide in controlling Fall Armyworm (FAW), Spodoptera frugiperda in maize (Zea mays L.). A Completely Randomized Design (CRD) was used, with six treatments: Control (distilled water), Uppercott (Cypermethrin 30g/L + Dimethoate 250g/L), Tithonia diversifolia (Mexican Sunflower), Jatropha curcas (Physic Nut), A. annua (sweet wormwood) annua (Sweet Warmwood), and Azadirachta indica (Neem), each at four concentrations (50, 100, 150, and 200 g/L), with three replications per treatment. Data were collected on larval mortality, statistical analysis was performed using Analysis of Variance (ANOVA) procedure with SAS software, and treatment means were compared using Student’s Newman-Keuls (SNK) test at a 5% level of probability. The study found that plant extracts had a significant effect (P<0.05) on larval mortality. At a concentration of 200 g/L, the control treatment showed the lowest larval mortality (3.7%). A. annua (sweet wormwood) annua leaf extract caused 33.3% larval mortality, while Tithonia diversifolia leaf extract resulted in 46.7% larval mortality. Jatropha curcas leaf extract increased larval mortality to 66.67%, and Azadirachta indica Seed Extract caused the highest larval mortality of 86.7%, which was close to the efficacy of the synthetic insecticide Uppercott, which achieved 100% larval mortality. These findings highlight the potential of Azadirachta indica and Jatropha curcas extracts, especially at high concentrations (150g/L), as promising bio-insecticides, offering comparable control to synthetic insecticides like Uppercott. Therefore, farmers are strongly encouraged to use Azadirachta indica and Jatropha curcas leaf extracts as eco-friendly alternative to synthetic insecticides in managing Fall Armyworm.