Evaluation of plant defence related biomolecules produced by nematophagous fungi in tomato against root-knot nematode

The aim of this study was to evaluate the plant defence-promoting ability of various nematophagous fungi like Arthrobotrys oligospora, Paecilomyces lilacinus and Pleurotus sp. against root-knot nematode Meloidogyne incognita in tomato by determining the plant defence-promoting biomolecules, viz. hydrogen peroxide, superoxide dismutase, catalase, peroxidase and polyphenol oxidase. It was observed that soil application of A. oligospora along with farmyard manure (FYM) enhanced the activity of defence-related biomolecules from day 30 to day 60 after transplant, thereby showing its immense potential in controlling root-knot nematodes in tomatoes. The highest mean defence-related enzyme activity in plants was recorded in the treatment containing nematode-infested soil + FYM + A. oligospora with 97.65 enzyme unit (EU) mg–1 protein min–1 of hydrogen peroxide, 1.54 EU mg–1 protein min–1 of superoxide dismutase, 4.57 EU mg–1 protein min–1 of catalase, 9.45 EU mg–1 protein min–1 of peroxidase and 5.89 EU mg–1 protein min–1 of polyphenol oxidase. The gall production in nematode-infested soil had also reduced drastically after the application of the nematophagous fungi