Photosynthetic productivity of summer barley in conditions of Forest-steppe Right-bank

Abstract

The purpose. To determine influence of complex application of doses of nitric fertilizers and growth regulating substances on display of character of formation of photosynthetic and grain efficiency of different varieties of summer barley in conditions of Forest-steppe Right-bank. Methods. Applied general scientific methods (dialectics, experiment, analysis and synthesis, method of hypotheses), and special: field - for studying interaction of subject of researches with weather conditions and receptions of technology of cultivation; visual; measuring and weight; quantitative; physiological; laboratory — for establishment of qualitative characteristics of soil of test plot; dispersive, correlation and regression — for determination of reliability of distinctions between factors, pair and plural dependences. Results. Influence of complex application of doses of nitric fertilizers and regulators of growth of plants on formation of photosynthetic and seed efficiency of summer barley of varieties Nabat and Vinnitskiy 28 is investigated. It is noted that in variants of experiment with maximal parameters of photosynthetic efficiency, in particular accumulation of organic substance (1045,9–1035,1 g/m2), pure efficiency of photosynthesis (5,5–5,9 g/m2), content of chlorophylls «a+b» (2,29–2,14 mg/g of crude weight), it is observed the maximal productivity of grain of culture. The highest productivity of grain for varieties Nabat (6,39 t/hectare) and Vinnitskiy 28 (5,78 t/hectare) was gained in variants of experiment where on phosphoric-potash background P45K45 they entered nitric fertilizers in doze of N90 and morpho-regulator Terpal in a phase of the beginning of tubing. That was more accordingly on 2,21 t/hectare, or 52,8% and 1,97 t/hectare, or 51,7% in comparison with the control (on plots without fertilizers and growth regulators). Conclusions. Optimization of technology of cultivation of summer barley due to the balanced system of fertilizer, namely entering of nitric fertilizers in doze of N90P45K45 and application of growth regulators (Binom or Terpal), provides realization of genetic potential of varieties Nabat and Vinnitskiy 28 on 60–70% and level of productivity of grain — 6,39 and 5,78 t/hectare accordingly.