Physiological Comparison of Wheat and Maize Seedlings Responses to Water Stresses

The aim of the study was to investigate specific responses of spring wheat (C-3 photosynthesis) and maize (C-4 photosynthesis) to drought and flooding stress. Analyses of water content, gas exchange intensity, photosynthetic apparatus activity, chlorophyll content, plant height and biological membrane integrity were performed on the 10th day of drought and flooding in both species at the third leaf stage. A specific response of wheat under both drought and flooding conditions involved an increase in ETo/RC ratio, describing electron transport flux converted into a single reaction center in PSII. Correlations between electrolyte leakage and the probability of electron transport beyond the plastoquinone Q(A), and the amount of energy used for the electron transport were also found. A specific response of maize during flooding was the increase of stomatal conductance. Additionally, a significant correlation between P-N/C-i and relative water content was exhibited. Furthermore, the parameters differentiating the studied species only under stressful conditions were rendered. The application of such parameters can be widely used, e.g., for studying the reaction of a potential cultivars to drought and flooding. Providing such information to potential farmers can help better select cultivars for their environmental conditions.