Productivity and economic efciency of pear-tree plantations under optimized ferilization

Modern technologies of cultivation of seed crops plantations imply high efciency of fruit production while optimizing mineral nutrition of trees. The aim of the research is to increase fruit yield and economic efciency under optimized fertilization of pear trees in a re-growing rain-fed plantation. The results of the research, carried out to study the effect of optimized fertilization on yield capacity, fruit quality and economic efciency of replant pear-tree cultivation, cultivars Conference and Osnovianska (on vegetative rootstock quince A) in different age periods of growth and fruiting, were considered. Based on the results of agro-chemical analyses, the rates of nitrogen and potassium fertilizers were calculated in the way to compensate the lack of N–NO3 (by a nitrifcation ability of the soil) and forms of K2O, available for plant nutrition, and to make their content equal to optimal levels, scientifcally established for apple-tree and recommended for pear-tree plantations. It was found out that the highest yield capacity of the studied pear-trees was recorded with additional application of nitrogen and nitrogen-potassium fertilizers (background+N30, background+N30K30); it was higher by 27.2 and 36.7, 29.8 and 36.1 %, respectively, as compared with the yield capacity of unfertilized trees, and it was higher by 0.6 and 2.6, 4.7 and 4.2 % for the fertilized trees with the annual application of N90 P60K90 (production control); there the correlation of nitrogen, phosphorus and potassium of plant nutrition was less balanced, the total amount of fertilizers was larger though. Fertilization is a leading factor in the formation of the proftability of pear-tree agrocenosis. The use of various cultivars and practices to apply fertilizers in pear-tree plantations has an impact on the economic indicators of fruit production in different age periods of growth and fruiting. Key words: pear-tree, varieties, fertilization, yield capacity, marketable quality, revenue, proftability.