Soil fertility and productivity of apple orchard under a long-term use of different fertilizer systems

Abstract

An apple tree should be cultivated in the area with suitable soils, which can be used for growing of two or more generations of gardens for decades. This can be reached by creating and supporting an optimum level of inorganic nutrition of fruit trees applying a fertilizer. This fact is proved by the results of a long-term research on studying organic, mineral, organic and mineral fertilizer systems. The research has been conducted in the garden on dark-grey loam-clay soil since 1931. The most optimal soil fertility for an apple tree and its productivity were recorded maximum under the use of organic fertility system. Organic and mineral fertilizer system provided almost the same indexes, while the mineral fertilizer system provided the lowest ones. In the experimental nonirrigated garden the trees used less plant food compounds applied with manure because of limited soil water, while a great deal of them have been wasted. Soluble nitrogen compounds have been washed out of root layer into ground water, while phosphorus and potassium morphed into combinations and forms which were beyond the reach of plant nutrition. Turf and humus management system provides the same humus content in soil as application of 40 tons of humus per ha in a year after the use of fallow system. Herewith, there is no need for applying organic fertilizers but nutrition of trees and grasses only.