Prokopenko E. The efficacy of fertilizers application under common flax on chornozem opodzolic in the Right-Bank Forest-Steppe Zone of Ukraine

Object – regularity of the fertilizer effect on the yield of oily flax and nutritive soil regime. Purpose – to identify optimal and economically grounded doses and the ratio of mineral fertilizers applied under oily flax in order to get stable high quality seed yield and to ensure high return per unit of fertilizers due to yield increase on chernozem opodzolic in the Right-Bank Forest Steppe Zone of Ukraine. Methods – field, laboratory, agrochemical, mathematical, calculation-comparative trials. Theoretical results – the effect of fertilizers in content dynamics of movable compounds of nitrogen, phosphorus and potassium in the soil was defined, the effect of fertilizers on content dynamics of the main nutrition elements in oily flax organs was studied, the effect of fertilizers on the dynamics of land mass, the formation of leaf surface, net photosynthesis productivity and photosynthetic potential of oily flax fields was identified, economic uptake of the main nutrition elements from the soil was determined, their consumption per yield unit and the ration of the use from fertilizers were measured, the intensity of their balance depending on fertilizer was defined, the effect of fertilizers and chornozem opodzolic fertility on the seed yield formation of oily flax and its quality indices was identified, economic, power and agrochemical evaluation of fertilizer application under oily flax was given. Practical results – fertilization system of oily flax, taking into account its biological peculiarities, was recommended for the conditions of the Right-Bank Forest Steppe Zone of Ukraine; this makes it possible to get seed yield 18-20 cwt/ha. Payback of 1 kg of NPK by means of yield increase is 2.2-2.6 kg of seeds. Novelty – for the first time fertilization system for oily flax on chornozem opodzolic was developed for the conditions of the Right-Bank Forest Steppe Zone of Ukraine, it envisages the application of phosphorus and potassium at rate P30-60K60 under fall tillage and that of nitrogen - N60-90- under pre-sowing cultivation or locally before planting at rate N40P40K40, which ensures yield increase and high recoupment of mineral fertilizers. Degree of application – in 2006 the main results of the research were applied at farm enterprise "Agrofirm"Basis", Uman district, Cherkasy region on the area of 110 hectares and at farm partnership "Druzhba Ltd.", Uman district, Cherkasy region on the area of 85 hectares. The field is – agricultural chemistry and agricultural sciences.