Activity Profile of Defense Related Enzymes in Pearl Millet Against Downy Mildew (Sclerospora graminicola)

The activity profile of defense related enzymes viz., peroxidase, polyphenol oxidase, catalase, beta-1, 3 glucanase and phenylalanine ammonia-lase (PAL) with and without inoculation of pathogen Sclerospora graminicola (Sacc.) were evaluated in downy mildew resistant and susceptible parents and the crosses (RxS, SxR, RxR) of the pearl millet. The activity of all these enzymes significantly increased post inoculation of the seedlings suggesting induction of the defense response. The level of induction in these enzymes was significantly higher in resistant parent and also in crosses involving resistant genotype as a male parent. The pattern of inheritance as observed in the present investigation is indicative of a dominant mode of inheritance. When the data was analyzed and compared with the field data of downy mildew incidence it was also noticed that SxR crosses recorded comparatively low incidence of downy mildew.