Interrelationship between grain yield and physiological parameters of winter wheat nitrogen nutrition efficiency

This paper deals with interrelationship between grain yield and some physiological parameters of wheat plant nitrogen nutrition efficiency as well as interrelationships between these parameters and some yield related traits (biological yield, grain harvest index). The aim of such investigation is to affirm possibilities of using physiological parameters of wheat plant nitrogen nutrition efficiency as criterions in breeding on its grain yield. The investigation, conducted as three years field trials, included 30 wheat cultivars and perspective lines. There were studied: nitrogen content in the above - ground part of plant at anthesis, in grain, in straw and total nitrogen content at maturity, nitrogen harvest index, nitrogen reutilization, post - anthesis nitrogen accumulation and physiological efficiency of nitrogen. The positive and statistically high significant relationships between nitrogen content in the above - ground part of plant at anthesis, in grain and in straw, total nitrogen content at maturity, nitrogen reutilization and post - anthesis accumulation as physiological parameters and grain yield were registered in investigated material. Most of listed parameters, important by grain yield aspect, can be studied easily and measured before wheat vegetative period ends. The investigated parameters can be recommended as criterions for selecting of parental pairs and evaluating progeny in breeding of wheat on grain yield, considering to their determined interrelationships and their measurability.