Resistance to Bipolaris sorokiniana Schoem. in winter wheat indicated by conductometric method

Resistance to stresses is known to be under the plant genes control. In winter cereals which are sensitive to a rot pathogen Bipolaris sorokiniana Schoem., the metabolic processes, i.e. the energy accumulation, respiration intensity, enzymatic activity, polysaccharide and amino acids synthesis, K input, cell membrane intactness, change significantly. As a result, a part of intracellular electrolytes are lost. A variety resistance (tolerance) is usually evaluated as the yield loss which indicates an agronomic resistance to disease, and by estimating the physiological, biochemical and biophysical parameters during early vegetation which reflect a biological resistance. We used a conductometric method to estimate the resistance of 15 winter wheat and winter rye varieties under plant inoculation with B. sorokiniana Schoem. in a climatic chamber, and then the 4 winter wheat varieties with contrast characteristics in that test were examined in pot trials. The correlations between different indexes of early plant reaction to biotic stress were shown to be really tight and reliable. It was revealed that the electrophysical parameters of leaf cell membranes changed equal to root and sprouts length in 14-day seedlings, and to their biomass as an integral growth index. Thus, the electrophisical parameters are adequate to biometric, psychopathological, physiological parameters and yield losses, and can be used as the indicators for plant resistance to stress caused by B. sorokiniana Schoem. infection.