SEQUENTIAL BIOCHEMICAL CHANGES IN ROOTS OF CALLISTIPHUS CHINENSIS LINES RESISTANT AND SUSCEPTIBLE TO MELOIDOGYNE INCOGNITA RACE 1

Two lines of china aster, Callistiphus chinesis, viz., AST-5 and IIHR-55 (Kamini) developed at the Division of Ornamental Crops, Indiana Institute of Horticultural Research, Bangalore, resistant and susceptible, respectively, to the root-knot nematode, Meloidogyne incognita race 1, were analysed to record the post-infection sequential biochemical changes in their roots. The results indicate that there were significantly higher contents of total phenols and total proteins, and higher activity of polyphenol oxidase in infested AST-5 roots in the first two weeks after infection which declined in third and fourth week of infection, compared to that of uninfected AST-5 roots and infected and healthy IIHR-55 roots. The activity of phenylalanine ammonia lyase was comparatively higher in the infected AST-5 roots compared to its uninoculated control and IIHR-55 roots. The percentage increase in PAL activity was higher in infected AST-5 roots from 21 days after infection.