INTEGRATED MANAGEMENT OF TOBACCO LEAF CURL VIRUS DISEASE TRANSMITTED BY WHITEFLY, BEMISIA TABACI IN FCV TOBACCO

Abstract

Tobacco whitefly, Bemisia tabaci Gennadius, a vector of tobacco leaf curl virus disease (TLCV) is one of the major insect pests of FCV tobacco in southern black soil (SBS) region of Andhra Pradesh. Evaluation of four pest management modules against TLCV was carried out for two consecutive years i.e. from 2016-17 to 2017-18 at CTRI Research Station, Guntur. Observations were recorded on TLCV infected plants, natural enemy population on Jowar & tobacco and yield data of tobacco. The data revealed that IPM module (M1) exhibited 81.45% reduction of TLCV disease, 6.97% increase of cured leaf yields with incremental benefit cost ratio of 2.84 over untreated control. Whereas, Chemical control module (M2) reduced TLCV disease by 83.79%, increased cured leaf yields by 7.74% and incremental benefit cost ratio of 3.16 over untreated control. Jowar border alone (M3) reduced 25.86% TLCV, increased 1.80% cured leaf yields with 2.76 incremental benefit cost ratio which was significantly superior to untreated control. Both IPM module and chemical control module were on par and significantly superior in reducing TLCV infected plants over the M3 & M4 modules. The treatments with chemical spray schedules showed drastic reduction of natural enemy population in tobacco. Predator population in tobacco was more (42.5/ plant) in jowar border plot and control plot (39.0/ plant). In pesticide applied plots (M1 and M2), predator population recorded in tobacco were 9.9 and 9.0 per plant, respectively. Coccinellid predators were dominant followed by spiders, wasps and syrphid flies. Predator population on jowar plants was more (12.1/plant )in M3 and it was comparatively less (9.0/plant) in M1 due to the effect of pesticides. The present study helps in reducing pesticide application in tobacco which in turn reduces pesticide residues in the cured leaf.