Abstract

EFFECT OF TIME OF INOCULATION AND DELIVERY SYSTEMS ON BIOLOGICAL CONTROL OF FUNGAL INFECTIONS OF TOMATO (SOLANUM LYCOPERSICUM) BY PSEUDOMONAS SPECIES

Balkrishna M. Sandikar*

Abstract

Six Pseudomonas isolates i.e. P. aeruginosa13, P. aeruginosa 58, P.putida71, P. fluorescens106, P. aeruginosa117, P. aeruginosa154obtained from rhizosphere of healthy tomato plants with potentantifungal activity against the phytopathogenic Pythium and Fusariumspecies were used to study biocontrol of tomato (Solanumlycopersicum) plants by pot culture experiments. Active nutrient brothcultures of these Pseudomonas species were applied by three deliverysystems- soil amendment, seed coating and foliar spray, at threedifferent periods, i.e. before sowing, at the time of sowing and after thesowing of seeds. All the Pseudomonas cultures were provedsuccessful to control tomato plants from Pythium and Fusariuminfections, although with different efficiencies. Biocontrol of fungalinfections of tomato was found to be more effective by soil amendment (>50%) while leasteffective by foliar spray (34-60%). Application of Pseudomonas cultures before sowing ofseeds was found to be more effective in case of all the isolates. Biocontrol efficiency wasfound to be higher in case of P. aeruginosa 154, P. aeruginosa58 and P. aeruginosa13. Weconclude that, application of these Pseudomonas cultures is more significant for biocontrol offungal infections of tomato plants especially by soil amendment, before sowing of seeds.

Keywords: Biocontrol, Pseudomonas, Phytopathogens, Pythium, Fusarium.