Different Physiological Reactions at Vegetative and Generative Stage of Development of Field Bean Plants Exposed to Flooding and Undergoing Recovery

Plants at various stages of growth are differentiated in their susceptibility to environmental stresses and possibility of regeneration during recovery period after cessation of stress. The role of antioxidative enzymes in the stabilisation of the physiological state of field bean plants was studied. Catalase, peroxidises activity, and hydrogen peroxide accumulation were determined after 1 and 7 days of flooding and after 1 and 7 days of recovery from flooding. The influence of flooding on plants growth was analysed on the basis of leaf area index (LAI), relative growth rate (RGR) and net assimilation rate (NAR). Changes in antioxidative enzymes caused by flooding applied at vegetative stage were reversible. In generative plants, antioxidative enzymes were activated to a greater extent during recovery period and in contrast to vegetative plants did not attain the control level after that period. The reduction in growth was greater when flooding stress was applied at vegetative stage. Vegetative plants regardless of the stabilisation of antioxidant system were not able to restore the physiological function to attain the optimal growth level after flooding. Probably other injuries caused by flooding had a dominant effect on enzymatic antioxidant changes during stress period.