The toxicity of the extract of tobacco leaf Nicotiana tabacum L, marigold leaf Tithonia diversifolia (HAMSLEY) and citrus japansche citroen peel Citrus limonia against citrus psyllid (Diaphorina citri Kuwayama), the vector of citrus HLB disease

Abstract

Potential insecticides generated from several plants or some plant wastes are used to control citrus psyllid Diaphorina citri. The aim of the study was to determine the toxicity of botanical insecticides from the extract of tobacco leaf, marigold leaves and Japansche citroen (JC) citrus peel against D. citri. The three plants, which were extracted with five kinds of solvents, namely acetone, distilled water, dichlormethane, hexane and methanol by maceration method. The test used leaf dipping method at 10% concentration with control and imidacloprid chemical insecticide as a comparison. The results showed that tobacco extract with all solvents was effective in controlling D. citri, starting at 1 day after treatment (DAT) with 44-92% mortality. The effective marigold leaf extract was those with the solvent of distilled water, dichlormethane and acetone. The mortality at 8 DAT was 100% and 70% and 74% respectively. Meanwhile, JC citrus peel extract with acetone, methanol and dichlormethane solvents were effective to control D. citri with the mortality at 8 DAT, the mortality reached 98%; 88% and 70% respectively. Thus, botanical insecticides of tobacco, marigold and JC orange peel with certain solvents can be used as controller of D. citri.