Fruit growing
and viticulture of South Russia
Manage of water regime
Use of drip irrigation or fertigation in apple-tree plantations contributed to the decline of fruit shattering, an increase of their average weight and getting in some years of surplus up to 26-50 % compared to the naturally growing plants. However, to overcome the periodicity of fructification of apple-trees was not possible. In the summer conditions in the south of Russia drip irrigation did not affect the change in temperature and humidity of the ground layer of the air and, accordingly, did not contribute to the generative bud setting.
Problems of water supply of fruit trees on middle-grown rootstocks in the forest biocenosis are considered in the article. The expediency of assessment of water balance on the condensation of moisture vapor to produce more correct results in the analysis of crop yield is established
Three-year application of low-volume irrigation methods with the help of drip watering has caused some changes in the properties of chernozem soil in the orchard of apple trees, however a significant reduction in fertility is not revealed. In conditions of insufficient moistening of the Stavropol region the use of subsoil irrigation provided reliable additional yield of apple Liberty in drought years, and also increase in the average weight of fruit
Apple varieties have different response to fertilization and changes of root nutrition conditions. For three years, we studied the effect of fertigation on the content of nutrients in the leaves and the yield capacity in apple cultivars: Lobo and Spartan, grafted on rootstock 62-396. Planting scheme is 4 x 1 m, trees were cultivated on meadow-chernozem and dark gray forest soils. The experiment on meadow-chernozem soil was carried in AO "Dubovoe" (Tambov region), the experimental plot on dark gray forest soil was located in OAO "Agronom-Sad" (Lipetsk region). Leaf samples for analysis were taken during periods of the highest demand for the appropriate nutrients: phosphorus at the end of May, nitrogen at the end of June, and potassium in mid-August. Soil samples were taken before orchard planting and in August of the 3rd year of the study. The negative impact of drip irrigation on the content of soil nutrients was noted: the acidity increased on the meadow-chernozem soil, in both types of soil the content of available nitrogen decreased, as well as phosphorus and potassium in the upper layers of the soil. The content of the main nutrients in the leaves under fertigation depended on the variety response to fertilization, as well as on the soil type: the Lobo variety had a higher content of the studied nutrients in the leaves when fertigated on dark gray forest soil. The Spartan variety had a higher content of nutrients in leaves during fertigation on meadow-chernozem soil. Fertigation had a significant effect on increasing the yield capacity of Lobo variety on dark gray forest soil, and the yield capacity of Spartan variety on meadow-chernozem soil.