Insecticidal Activities of Aqueous Extracts of Five Nigerian Aromatic Spices against Garden Eggplant Defoliators and Fruit Borer Leucinodes orbonalis Guenee: Lepidoptera: Crambidae

Abstract

 The study evaluated the prospects of aqueous extracts of five Nigerian spices against garden eggplant defoliators and fruit borer (Leucinodes orbonalis) in the field. The treatments consisted of Piper guineense (black pepper), Aframomum melegueta (aligator pepper), Eugenia aromatica (cloves), Zingiber officinale (ginger), Capsicum annum (chilli pepper) and untreated check (control). All the aqueous extracts evaluated reduced leaf damaged by defoliators on garden eggplant compared to control. P. guineense, with mean value of 11.02 number of perforations, was the most effective against defoliators, followed by E. aromatica (12.97) reducing leaf damage by 39.64 and 28.74%, respectively. However, their efficacies against defoliating insects were not significantly different (p > 0.05) among other extracts. P. guineense was also more effective than other spices against infestations by garden eggplant fruit borer and larvae density on fruits with mean values of 1.07 and 0.47, respectively. Plots treated with P. guineense recorded highest fruit yield (629 g/plant), followed by E. aromatica (219.3 g/plant). Piper guineense and E. aromatica extracts were thus more efficacious than other spices against defoliating and fruit boring insects of garden eggplants. Adopting the applications of extracts from these spices in home garden will minimize environmental and health hazards associated chemical pesticides and enhance healthy living among the populace.

Keywords: spices, aqueous extracts, garden eggplant, Leucinodes orbonalis.