Influence of foliar feeding on productivity and the quality of apple fruit in conditions of Krasnodar Territory

Abstract

The article presents the results of a field experiment to study the effectiveness of the special complex fertilizers of various compositions in the fruiting plantings of dwarf apple trees Renet Kubanskiy and Prikubanskoe varieties on rootstock SK4 in the Central zone of Krasnodar Territory. Analysis of the results of the study for 2013-2018 revealed a significant advantage of the option with the systematic use of fertilizing in terms of productivity of apple tree. The number of fruits per square meter of crown projection area on the background of leaf feeding annually exceeded the control variant (without fertilizers) by 8-30 % (Renet Kubanskiy variety), 10-60 % (Prikubanskoe variety). The materiality of exceeding the indicator is proved statistically at the 5 % level of significance. Increased reproductive function throughout the study period was due to an increase in the number of green pigments in the leaves of shoots. On the example of the Prikubanskaya apple varieties was determined that the total content of chlorophylls (a+b) in the first decade of June was higher than in the control variant 1.9- 27.5 %, and in the third decade of August, in the range of 2.0 to 44.5 % . Leaf feeding of trees with water solutions of special fertilizers provided an increase in the quality of apples, determined during the period of removable maturity. Weight of the fruit on background of fertilizing annually exceeded the control variant (without fertilizers) was 1.1 to 3.8 % (Renet Kubanskiy variety), 1.1-3.9 % (Prikubanskoe variety). The most stable significant excess of this parameter was in Prikubanskoe apple varieties and in Renet Kubanskiy apple varieties at planting scheme 4.5×1.2 m. In terms of commercial quality, apples were characterized as the highest and first commercial grades, since against the background of foliar applications at the main mass the coloring of fruits had an area ranging from ½ to ¾ of the surface (Prikubanskoe variety). The output of high-quality products (the highest and first commercial grades) in the variant with the use of dressings significantly exceeds the control option. At the intensity of hydrothermal factors in the summer, the receiving of foliar feeding provides a higher level of adaptation of the pigment apparatus to environmental conditions in apple plants and increases the yield of high-quality fruits.