Efficacy of Three Essential Oils in the Management of Cryptolestes ferrugineus (Steph.) Infesting Stored Maize Grains in Lafia, Nigeria

Three edible essential oils extracted from West African Black Pepper (WABP), Piper guineense Schum and Thonn., Clove, Syzgium aromaticum (L.) Merril and Percy and Ethiopian Pepper, Xylopia aethiopica (Dunn) A. Rich were investigated for their effectiveness in suppressing the number and adult emergence of flat grain beetle, C. ferrugineus. Five pairs of adult C. ferrugineus were treated with the three edible essential oils at the rates of 0.25, 0.5, 0.75 and 1.0mg/10 g broken maize grain at 20% of 109 maze grains. The experiment was carried out as treatment before infestation (TBI) in the laboratory in a completely randomized block design, replicated four times. In comparison to the treatment and control (0.00 mg), the entire plant oil significantly (P<0.05) reduced the population of C. ferrugineus by causing high mortality rates and completely prevented subsequent adult emergence. Treatments with Ethiopian Pepper and WABP oil at the rates of 0.25 ,0.5, 0.75 mg/l 0 g broken maize recorded up to 90% mortality while clove oil recorded 100% mortality at all the dosage rates applied when compared with the control. The potential effectiveness of all the three edible essential oils implies that maize stored as grits could be adequately protected against C. ferrugineus, thus reducing their infestation and damage on maize grains.