Effects of Pongamia pinnata and Adhatoda vasica extracts on tea mosquito bug, Helopeltis theivora waterhouse (hemiptera: miridae)

Experiment carried out with the aqueous plant extracts of Pongamia pinnata and Adhatoda vasica at 10.0, 8.0, 6.0, 4.0 and 2.0% concentrations showed significant effect on growth and development of tea mosquito big Helopeltis theivora Waterhouse (Hemiptera: Miridae). The duration of nymphal instar was lengthened significantly (P=0.05) by both the extracts, of which P. pinnata had pronounced effects. Although the duration of 4th instar nymphs was prolonged most of the emerged nymphs died later due to deformities. The weight of all the nymphal instars significantly decreased and the mortality varied between 20 to 35%. The adult emergence varied from 25.30 -44.30% (male) and 28.30- 45.90% (female) with P. pinnata and 28.50–38.60% (male) and 32.50–48.72% (female) with A. vasica.