Insecticidal and repellent activity of some plant extracts against Myzus persicae (Sulzer) and Brevicoryne brassicae (Linnaeus)
Sunil Kumar Yadav and Shweta Patel
The crude aqueous extracts from Ageratum conyzoides (L.), Parthenium hysterophorus (L.), Lantana camera (L.), Solanum nigrum (L.), Cannabis sativa (L.), Calotropis gigantean (L.), Livistona chinensis (Jacq.), Cassiaangustifolia (Mill.) were tested for their insecticidal and repellent activity against Myzus persicae (Sulzer) and Brevicoryne brassicae (Linnaeus). Leaves of mustard were treated with different concentrations (1%, 3%, 5%, 7% and 10%) by spraying with potter’s tower and aphids were allowed to feed for 72 hours. The results revealed that percent mortality was directly related to concentration of plant extract and exposure period. The treatments of C.angustifolia seeds and C.angustifolia leaves were the most effective causing maximum mortality in B. brassicae (up to 100% mortality at 10% and 7% concentrations, respectively, after 72 hours of exposure period) and M. persicae (up to 96.67 and 93.33% mortality, respectively, at 10% concentration after 72 hours of exposure period). Whereas the repellent activity was inversely related to concentration of plant extract. In general, the repellent activity was increased up to 48 hours of exposure at low concentrations. However, repellent activity was low at higher concentrations. These plants can be used as botanical insecticide to manage the insect problems.