Induction of Defence Enzymes using Bio-Agents in Tomato Infected with Root-Knot Nematode, Meloidogyne incognita

摘要

An experiment was carried out in root-knot nematode infested soil (2 J/g soil) to assess the induction of defence enzymes PO, PPO, PAL and SOD by bio-agents against Meloidogyne incognita in a susceptible variety of tomato. Bio-agents Trichoderma viride, T. harzianum, Pochonia chlamydosporia and Paecilomyces lilacinus each @ 2g and 4g per kg soil and Pseudomonas fluorescens @ 4g/kg soil (standard check) were added to soil. Application of bio-agents increased the level of PO, PPO, PAL and SOD in tomatoroots. Among all the treatments application of 7. viride and P. fluorescens @ 4g/kg soil were found to be the best treatments to enhance enzymatic activity. Among enzymes the PO was found highest in tomato roots during different times of observation followed by SOD, while PPO and PAL were observed in low quantity. The enzyme activity showed gradual increase from 7 DAI onwards to 28 DAI in plant roots treated with bio-agents as compared to untreated ones. The lowest enzyme activity was recorded at 60 DAI in untreated control plant roots. T. viride @ 4g/kg soil was found to improve plant growth of tomato as also reducing number of galls per plant (20.50), number of egg masses per plant (14.17), number of eggs per egg mass (80.00), nematode population/200cc soil (180.33) and total nematode population (2036.00) in tomato and was at par with P. fluorescens.