Seeding baculovirus HpNPV in the epicentre populations of teak defoliator, Hyblaea puera to prevent large-scale outbreaks

The defoliation caused by Hyblaea puera can result in approximately 44% reduction in the annual volume increment of teak, a major timber tree. Several management options used in the past to control the pest were not effective due to high cost and environmental problems. In the present study we have used the vertical transmission characteristics of Hyblaea puera nucleopolyhedrovirus (HpNPV) for cost-effective and environment-friendly control of the most devastating pest. First, a laboratory experiment was conducted to verify the vertical transmission of HpNPV and later field spraying was done to study the effect under natural conditions. Vertical transmission of HpNPV in the labo­ratory ranged between 13% and 59%. The sublethal transmission caused reduction in pupation, adult emergence, male and female longevity, egg-laying period, fecundity, hatching of F1 eggs, F1 mortality, F1 pupation and F1 fecundity, but had no influence on the F2 survival compared to the control. Spraying of HpNPV in the epicentre population of the pest resul­ted a viral epizootic at the F2 generation and led to collapse of the host population. Seeding of HpNPV in the epicentre populations of the teak defoliator has been proved to be an economical and environment-friendly method for management of the pest.