Comparative study of the insecticidal activity of a high green plant (Spinacia oleracea) and a chlorophytae algae (Ulva lactuca) extracts against Drosophila melanogaster fruit fly.

OBJECTIVES

Currently, the global interests tend to take advantage of the plant world as a renewable source of a natural and effective molecule, to find an eco-friendly, cost-effective, and less toxic alternative to the current synthetic pesticide. In this context, the present research was carried out in an attempt to study the insecticidal activity of extracts and pigments derived from the green plant Spinacia oleracea and the green alga Ulva lactuca against the fruit fly Drosophila melanogaster as an alternative to chemical insecticide.

METHODS

The toxicity of the aqueous, acetonic and ethanolic extracts as well as of the purified pigments (Chlorophylls and carotenoids) was determined by complementary in vivo tests (application by spraying oranges, toxicity by ingestion and repellent activity). Interestingly, each one of these methods corresponds to a specific mode of exposure.

RESULTS

Results showed that acetone extracts, which are rich in green pigments, present the best insecticidal activities. On the other hand, the purified chlorophyllian pigments exhibited an interesting activity only by spraying method. Regarding the repellent activity, the aqueous extract of spinach displayed higher effectiveness.

CONCLUSION

Our study suggests the potential of tested plant and algal extracts, as well as of chlorophyllian pigments, to provide a safer alternative way to the use of synthetic pesticides.