Lethal and sublethal effects of emamectin benzoate on the tomato leafminer, Tuta absoluta

Tuta absoluta is one of the most important pests of tomato in many countries. Emamectin benzoate (EB) is widely used in the control of lepidopteran pests, but there is sparse information available regarding its sublethal effects on T. absoluta. In this research, the lethal and sublethal effects of EB were investigated on T. absoluta under laboratory conditions. Acute toxicity bioassay was carried out on 2nd instar larvae using residue contact method. The LC50 value was 14.50 mg a.i. L−1, for 24 h exposure time. LC10 and LC30 of the insecticide was used for sublethal effect study. The insecticide significantly extended the larval developmental time at LC30. Pupal weight, fecundity and longevity of female adults were decreased at both tested concentrations. However, the LC10 and LC30 of the insecticide had no significant effects on pupal period, egg hatchability, and male adults’ longevity at sublethal effect study. These results suggest that the sublethal effects of EB might affect pest population dynamics significantly by delaying its development, and decreasing its reproduction. Hence, this bioinsecticide can be used in integrated pest management program of T. absoluta if its efficacy proven under the field and greenhouse conditions.