Field application of Pseudomonas fluorescens, Bacillus subtilis and Trichoderma viride for the control of Meloidogyne incognita (Kofoid and White) Chitwood on sugarbeet.

Abstract

Field experiments were conducted to assess the efficacy of Pseudomonas fluorescens, Bacillus subtilis and Trichoderma viride against the root knot nematode, Meloidogyne incognita (Kofoid and White) Chitwood infesting tropical sugarbeet cv. Indus. The biocontrol agents were applied at 2.5 kg/ha and compared with carbofuran (1 kg a. i./ha), There was a significant increase in the plant growth parameters and decrease in nematode population in all the treatments compared to control. Among the biocontrol agents tested, P. fluorescens recorded significantly higher growth parameters and lower nematode population and was as effective as carbofuran. Induction of defence enzymes, viz., peroxidase, polyphenol oxidase and phenylalanine ammonia lyase, was studied in all the treatments. Enzyme activity was significantly higher in P. fluorescens treated plants, followed by T. viride and B. subtilis .