Vol. 11, Issue 4 (2022)

Author(s):
R Mouniga, B Anita, A Shanthi, A Lakshmanan and G Karthikeyan

Abstract:
Root knot nematode, Meloidogyne spp. causes severe yield losses in vegetable crops. Chitosan is one of the most abundant biopolymer available worldwide next to cellulose. It is known to have anti-nemic, anti-fungal and anti- bacterial properties. Application of chitosan induces systemic resistance in tomato plants against pathogens by increasing phenolic content and antioxidant enzymes viz., Polyphenol oxidase, Superoxide dismutase and phytoalexins. A study was conducted to study the phenol content and activity of antioxidant enzymes, polyphenol oxidase and peroxidase activities in root knot nematode infected tomato plants treated with chiotsan nanoparticles. The antioxidant enzymatic activities were recorded after 25^th day of nematode inoculation. It was observed that the phenolic content increased due to the application of chitosan nanoparticle in nematode infected plants (174.32 µg/g of root) compared to 160.37 µg/g of root in untreated plants. Similarly the peroxidase and polyphenol oxidase activity also increased in chitosan nanoparticle treated nematode infected plants. The study revealed that chitosan nano particles protect plants from root knot nematode infection by increasing the phenol content, peroxidase and polyphenol oxidase activity and induce systemic resistance against nemayodes.