ChileanJAR

To reduce the dependence on the sometimes unwise use of synthetic pesticides in fruit and vegetable plantations, the toxicity and repellence of Peganum harmala L. (Zygophyllaceae) acetonic seed extract was assayed against several insect pests. For contact toxicity, 3- to 4-d-old individuals of Aphis fabae Scopoli, A. gossypii Glover, A. nerii Boyer de Fonscolombe, and Myzus persicae (Sulzer) were included, as well as 1- to 7-d-old adult Tribolium castaneum (Herbst). Repellent effect experiments were conducted on adult, 1- to 2- and 3- to 4-d old M. persicae individuals. At 60 mg mL^-1, the topical bioassay mortality percentage was significantly higher in A. gossypii than in A. fabae and A. nerii after 12-72 h. Mortality of the treatments on M. persicae was 87.1% and 90.0% after 24 and 48 h, respectively, and significantly higher than A. fabae and A. nerii during this period. At 60 mg mL^-1, the mortality of T. castaneum was much lower than that of the aphid species. The highest repellent index (over 72%) was observed on 1- to 2-d-old M. persicae individuals.