Insecticidal activities of 5 plant extracts against Solenopsis invicta

Solenopsis invicta is an invasive pest in China. Active substances were extracted from Excoecaria cochinchinensis、Lantana camara、Nerium indicum、Thevetia peruviana and Allemanda neriifolia with Soxhlet extractor and their bioactivity to S. invicta was tested. The results indicated that all 5 plant extracts had insecticidal activity. The mortality of S. invicta increased with the concentration of the extracts and differed significantly among the plant extracts at different concentrations. Toxicity test showed the toxicity of 5 plant extracts to fire ants after 24 hours from high to lowwas A. neriifolia,H. peruviana,E. cochinchinensis,L. camara and N. indicum,the median lethal dose( LD50) was 61. 3477,89. 9868,95. 8682,110. 9066 and 176. 7998 mg / m L respectively.