Population dynamics of red ant, Oecophylla smaragdina in cashew orchards and its augmentation for biological control

Abstract

Augmentation of red ant (Oecophylla smaragdina) in cashew orchard was found to effectively reduce tea mosquito bug Helopeltis antonii population but information on the population dynamics of it is lacking at present. The population of red ant in different seasons was assessed by observing the presence and counting the live nests constructed on host plants. Augmentation by providing food was also assessed. Only less than 50 % of the cashew trees were harboured by red ants in different orchards and during rainy season, there was a further reduction in ant population and then a gradual increase during post rainy season. Food provision resulted in 10.3 fold increase in number of nests compared to 1.35 fold increases in control over a period of just 33 days. The results show that we can move from natural control to augmentative biological control for successful management of Tea mosquito bug in cashew.