Efficacy of plant leaf extracts on termites under laboratory conditions

Abstract

The attack of crop plants by termites leads to serious crop damage, yield loss and contamination of products. The use of synthetic insecticides to control termites cause aquatic and environmental pollution and development of resistance by the termites. A broad range of plants were reported to insecticide properties. Therefore, the current study was aimed to determine the efficacy of locally available plants at different concentrations for the management of termites. The study was conducted under laboratory conditions to evaluate the toxic effect of five different plants such as Azadirachta indica, Samadera indica, Allium sativum, Z. officinale and Justicia adhatoda on termites at different concentrations like 100, 300, 600, 900 and 1000 mg/mL. Aqueous plant extracts were used for the bioassay procedure with 10 worker termites and three replications were maintained for each experiment. Form the results, it was found that A. sativum (86%) showed highest percentage of mortality which was followed by Z. officinale (82%), A. indica (81.33%), S. indica (74%) and J. adhatoda (72.67%) but, statistically there was no significant difference found between the plant extracts. 1000 mg/mL (97.33%) concentration of all the plant extract showed highest percentage of mortality. Based on time of exposure of termites to the extracts, 58.33% of mortality rate accrued when exposed to 20 min in the case of all extracts. It was found that 100 mg/mL was the minimum concentration required to kill 50% of the test organism (termites) for A. indica and S. indica and for A. indica and S. indica, LC50 was found at 300 mg/mL. Therefore, the study can be concluded that the percentage of mortality of tested termites was found concentration and time dependent as it was found to increase with an increase of the concentration and exposure time.