Biochemical response of resistance and susceptible genotypes of wheat to Karnal bunt infection

摘要

Karnal bunt (Neovossia indica) is a floral infecting disease expressing symptoms in grains at maturity. The infective aliantoid secondary sporidia multiplied on the boot leaf of both resistant (HD 29) and susceptible (WL 711) wheat genotypes while infection hyphae penetrated the stomata of WL 711 only thereby infecting the developing kernels. Young teliospores borne singly on sporogenous hyphae had smooth walls at 10 DAI and wall ornamentations started appearing at 15 DAI. Infection increased the level of total phenols, peroxidases and phenylalanine ammonia lyase in HD 29 at2 DAI while it decreased in WL 711. Rate of activity of polyphenol oxidase, B 1-3 glucanase and lipoxygenase increased 2-3 times at 2 DAI and reached maximum at 6 DAI in HD 29. High polymorphism was observed in malate dehydrogenase and esterase which resolved into 12 and 11 bands respectively in HD 29 and differed from WL 711 at a number of loci. It was interesting to note that hydroquinone could be detected before the start ofinfection while caffeic acid and L-tyrosine could not be traced.