Abstract
Gmelina arborea an indigenous tree species valued for its medicinal and timber properties is often attacked by numerous insect defoliators, miners, borers, sap feeders throughout the year including some major pests namely- Calopepla leayana, Tingis beesoni, Prioptera punctipennis, Alcidodes ludificator, Myllocerus sp. etc. As in agriculture the easiest management measure in forestry also comes in the form of different chemical pesticide treatments when the pest population is high and alarming. This investigation is a case study of such pesticide-induced resurgence among secondary insects of G. arborea in nurseries and plantations of Tamil Nadu. Two rare sap feeding insects Planococcus bendovi and Aleurolobus nandiensis in the nursery condition have been exposed directly and indirectly to the different concentrations of chemical pesticide treatment from 2020-2022 repeatedly. Over time the maximum dose of organophosphate pesticide dimethoate 30% EC (Rogor) failed to reach LC50 during insecticide efficacy (EA) testing against P. bendovi bioassay. Similarly, neonicotinoids thiamethoxam 25% WG (Actara) with maximum dose failed in A. nandiensis bioassay. Resurgence index (EHT) showed the higher abundance of A. nandiensis and P. bendovi in treated nursery beds compared to untreated nursery and field conditions by causing the mortality of 10 to 20 % (average) of planting stocks respectively.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
