BIO-INTENSIVE MANAGEMENT OF TOBACCO CATERPILLAR, SPODOPTERA LITURA FAB. IN KARNATAKA LIGHT SOILS

Abstract

Four bio-agents, two botanicals and two chemical pesticides were evaluated for two consecutive years (2008-09 and 2009-10) against tobacco caterpillar, Spodoptera litura which is an important pest in FCV tobacco nursery (var. Kanchan) in Karnataka Light Soils. Two sprays were given at 45 and 55 days of sowing. Observations on infested seedlings in each treatment were recorded before spraying, five and ten days after each spray. Per cent reduction of damaged seedlings over control after ten days of second spray was calculated for each treatment. The pooled data of two years revealed that except EPN, remaining treatments were significantly superior over control in reducing the damage at ten days of second spray. Lowest seedling infestation (2.50%) was recorded in chlorpyriphos 20 EC applied plot followed by novaluron 10 EC (5.66%). Among the bio-agents tested, Sl NPV and Bacillus thuringiencis var. Kurstaki proved better with 8.16 and 8.33% infestations, respectively. Both the botanicals also proved better with 10.66 (NSKS) and 12% (Calotropis) seedling infestations. The remaining two bio-agents, Nomuraea rileyi and EPN were least effective with 21.66 and 29.33% infestations, respectively. In control plot, the infestation was 30.66%. Similarly, per cent reduction of damaged seedlings over control was more (89.66) in chlorpyriphos 20 EC and less (9.16) in EPN applied plot. In the remaining treatments, it ranged from 28.33 to 83%. There was no significant difference between the two seasons. Hence, it is concluded that two bio-agents, viz., Sl NPV and Bacillus thuringiencis Var. Kurstaki proved better after chemical pesticides against tobacco caterpillar, Spodoptera litura in KLS.