Determination of Defence Enzyme Induction in Chilli in Response to Root- Knot Nematode, Meloidogyne incognita upon Oil Cake Application

An experiment was conducted with naturally infested soil of root-knot nematode 2 J2s/g soil to assess the induction of defence enzymes peroxidase (PO), polyphenol oxidase (PPO), Phenylalanine ammonia lyase (PAL) and superoxide dismutase (SOD) by oil cakes against M. incognita in a susceptible variety of chilli. Application of oil cakes castor, mahua, karanj and mustard were added to soil each @ 2.5 and 5.0 q/ha and neem cake @ 5.0 q/ha as a standard check. The role of selected oil-cakes in enzymatic activity was assayed in chilli roots infested with the root-knot nematode M. incognita. Application of oil-cakes increased the level of PO, PPO, PAL and SOD in chilli roots. Among all the treatments application of mustard cake @ 5.0 q/ha was found to be the best treatments to enhance enzymatic activity. However, standard check Neem cake @ 5.0 q/ha was found the best treatment to increase the enzyme activity against M. incognita in chilli roots. The enzyme activity showed gradual increase from 7 DAI to 28 DAI in plant roots treated with oil-cakes as compared to untreated ones. The lowest enzyme activity in among enzymes was recorded at 60 DAI in untreated control plant roots. Among enzymes the PO was found highest in chilli roots during different time of observations followed by SOD, while PPO and PAL were observed in low quantity.Among all the treatments application of mustard cake @ 5.0 q/hawas found the best treatments to improve plant growth character. As regard to nematode reproduction, mustard cake @ 5.0 q/ha soil proved best treatment in reducing number of galls per plant (20.33), number of egg masses per plant (14.50), number of eggs per egg mass (87.33), nematode population/200cc soil (203.50) and total nematode population of M. incognita (2283.83) in chilli.