POWDERY MILDEW INDUCED PHYSIOLOGICAL AND BIOCHEMICAL CHANGES IN PEA (Pisum sativum L.)

Plants respond to external stimuli by altering metabolic pathways, resulting in a cascade of different interrelated changes in physiological and biochemical processes. The incidence of powdery mildew in pea induces change in reducing sugars; non-reducing sugars, total sugars, electrolyte leakage and plant dry weight. Powdery mildew resistant and susceptible pea genotypes respond differentially to these traits. Powdery mildew resistant genotypes had comparatively less electrolyte leakage and less concentration of reducing, non- reducing and total sugars before and after infection. A significant increase in electrolyte leakage, non-reducing and total sugars was induced in susceptible genotypes after powdery mildew infection. The reduction in plant dry weight and reducing sugars after infection was more pronounced in powdery mildew susceptible and resistant genotypes respectively. All the traits being significantly correlated with disease severity can be an important component of an effective powdery mildew screening procedure in pea.