Incidence of Debarking by Caterpillar, Indarbela quadrinotata Walker on Casuarina equisetifolia in Tamil Nadu and its Management

Abstract

Casuarina equisetifolia is an exotic, fast growing, multipurpose tree species grown in Tamil Nadu. Altogether, about 40 species of insects have been recorded on C. equisetifolia in Tamil Nadu State. Among them, the bark eating caterpillar, Indarbela quadrinotata is considered as the most destructive pest in plantations. Wide variation in the infestation levels of bark eating caterpillar was noticed in Casuarina plantations grown under four agro-climatic zones of Tamil Nadu; the Cauvery Delta Zone showed highest intensity of attack, followed by the North Eastern Zone and the Southern Zone in the decreasing order of infestation, while the High Rainfall Zone was not affected by the pest. Plantations of younger age suffered from higher levels of infestation, compared to that of older ones. Among the climatological parameters, the minimum temperature had significant positive correlation with the pest infestation. Apart from the naturally occurring entomopathogenic fungus, Beauveria bassiana, the botanical formulations such as Melia azedarach seed kernel extract (5%), Pongamia pinnata seed oil (5%), Hydnocarpus pentandra seed oil (10,000 ppm) and Neem oil (5%) were found to be very effective in managing the pest under field condition.