Vajda P. Physiological particularities of winter wheat cultivars at the conditions of different water and nutrition

The thesis describes some metabolic in cultivars of winter wheat at different water and nutrients supply with use of radioactive isotopes 14C, 32P, 3H. The changes in water supply resulted in changes into metabolism of amino acids, synthesis, of sugars, organic acids, phosphorilated and polymeric compounds, consuming and incorporation of 14P in organic phosphates. These changes were more strongly manifested at stress conditions of drought, than in conditions of high humidity, causing oxygen shortage in rhizosphere. The cultivars specificity in reaction of winter wheat to different water supply was estimated. The main amounts of protein in grain were produced from nitrogen-containing compounds driven from other plant parts and a less from ammonium at flowering stage. The recycling of nitrogen in grains at blossom stage was less affected by drought then transport of nitrogen from roots. This effect on development protein complex in grains was stronger in drought-sensitive cultivars. It was a result of stress on stalk attractive force and decrease of respiration.