Chetveryk O. Winter hardines and grain yield of soft winter wheat, depending on the elements of the cultivation conditions ofthe eastern Fores-Steppe of Ukraine

Object: formation of winter hardiness and grain yield in winter wheat depending on climatic conditions of an area, variety, sowing dates and treatment by growth regulators. Aim: improvement of main elements of growing technology for the varieties of winter bread wheat with a various intensity for rising the level of winter hardiness and high grain yield of high-quality seeds in the conditions of the eastern part of the Forest-Steppe of Ukraine. Methods: field, laboratory, morphophysiological, measuring-calculating, biochemical, statistical, weighted. Novelty: for the first time in the conditions of the eastern part of the Forest-Steppe of Ukraine critical temperatures of winterkilling of a wide set of new varieties of winter bread wheat are defined; some peculiarities of the dynamics of winter-hardiness formation (accumulation and assimilation of carbohydrates in tillering nodes, duration of vegetative period) depending on the fore-crops, sowing dates and effect of growth-regulating preparation are stated. Results: varieties with a high degree of winter hardiness, adapted to their growing in the eastern part of the Forest-Steppe of Ukraine are identified. A new project to the state standard "Winter wheat. Methods for evaluating of soluble carbohydrates in tillering nodes"; has been developed the method for evaluating of chlorophyll content in winter wheat leaves has been designed and the patent for a useful model "Method for evaluating of chlorophyll content in winter wheat leaves" No 45171 of 26. 10.2009 is received; the cultivation technology for winter bread winter's varieties by means of sowing dates optimization and the establishment of optimal rates for the plant growth regulator "Vympel" permitting to obtain a high grain yield of qualitative seeds with a considerable economical effect in the conditions of the eastern part of the Forest-Steppe of Ukraine, has been improved.