Abstract

In field studies conducted in 1993, a 100-tree plot in a 17-year-old teak plantation at Nilambur, Kerala, was protected from Hyblaea puera, a serious defoliator of teak plantations, using a naturally occurring baculovirus (HpNPV) reported from this species. There were four major peaks of infestation during the year from March to June. A single foliar application of a crude preparation of HpNPV at the rate of 1 X 105 PIBs ml-1 of spray fluid at the earliest sign of each infestation gave a 70-76 level of control during the first two infestations. Control decreased to 33-43 by the third and fourth infestations, which was attributed to the occurrence of rain soon after applying the spray. In protected trees, the basal area increment was enhanced by 41, indicating the efficacy of HpNPV as a biocontrol agent