Evaluation of Pseudomonas fluorescens for the management of tomato early blight disease and fruit borer.

Early blight disease and fruit damage by Helicoverpa armigera are serious problems of tomato causing heavy losses in the yield. An experiment was conducted to evaluate the efficacy of talc based formulation of antagonist Pseudomonas flourescens (Psf) delivered through two different forms of substrate, farmyard manure (FYM) and vermicompost, for the management of tomato early blight disease. Two treatments of Psf, were selected Solarization of nursery soil + seeds and seedlings root dip treatment with Psf formulation + Use of FYM colonized with Psf formulation; Solarization of nursery soil + seed and seedlings root dip treatment with Psf formulation + Use of vermicompost colonized with Psf formulation. These were compared with farmer's practice and untreated control. The impact of all these treatments on tomato fruit borer, H. armigera was also studied. There was not much variation in plant growth parameters (plant height and canopy width) between all the treatments. Both biocontrol treatments (17.69% and 141.3 q acre-1; 15.70% and 139.4 q acre-1, respectively), as well as farmer's practice (10.25% and 208.5 q acre-1) were found to be better than untreated control (29.21% and 94.6 q acre-1) in reducing the incidence of early blight disease in tomato and increasing the marketable yield of tomato fruits. However, the farmer's practice was found to be significantly better than both biocontrol treatments of Psf in controlling fruit damage due to disease, as well as fruit borer. The effect of both bioagents enriched formulations i.e. FYM+Psf and vermicompost+Psf with respect to disease was significantly at par with each other, whereas they had no impact on the fruit borer incidence. The results indicated that either of biocontrol treatments of P. flourescens using farmyard manure and vermicompost, as delivery substrates, can be considered as one of the component along with chemical control in developing IPM programme for the management of early blight disease in tomato.