An epidemic outbreak of Sahyadrassus malabaricus (Moore) (Lepidoptera: Hepialidae) on Tectona grandis in Kolisalu-Pura, Karnataka, India

Teak (Tectona grandis) has been recognised as one of the most valuable premium wood in India. Its colour, fine grain and long durability are the most fascinating features of the wood. This species is widely established through large scale plantations in most part of Karnataka State. Teak saplings are exposed to serious insect pest problem mainly by the stem borer Sahyadrassus malabaricus causing severe damage on stem and affect the growth as well the quality of the wood. Occurrence of this pest is prevalent and magnitude of damage caused is severe in Kerala region. For the first time, in the teak plantation raised by the Karnataka State Forest Department in Kolisalu-Pura village located in the district of Shivamogga, Karnataka, an epidemic outbreak of this pest was observed and it is causing severe damage in young saplings. The damage was characterized by a hole in the main stem of the saplings and the larvae enter in to the stem through this bore holes and excavate a long cylindrical tunnel along the pith and causing damage. Hence the present study was undertaken to assess the pest outbreak in this area. The intensity of the pest incidence was moderate to severe level and the percentage of attack on the 1 to 2 years old saplings was 35-40%. Spraying or injection of the aqueous fungal solution of Beauveria bassiana at a concentration of 3.6 × 1010 or 3.6 × 108 at the entry hole of the pest after removal of the thick frass mat can control the pest in field condition.