Efficiency of foliar fertilization in table grapes cultivation under irrigation

Purpose: to assess the impact of foliar nutrition with soluble fertilizers Plantafol and Boroplus on economic and biological indicators and the efficiency of cultivation of table grape varieties in dry conditions under irrigation. The relevance of research is due to the problem of ensuring food security at the national and regional levels. Materials and methods. The subject of research was the grape varieties Codryanka (early), Rizamat (medium) and Moskovsky (late). The studies were carried out in the period 2015–2017 in Astrakhan region. Irrigation was carried out depending on the phase of development at a rate of 500–2250 cubic meters per hectare. The timing of the fertilization treatment was tied to the development phases, and the rates were in accordance with the manufacturer's recommendations. The methodological basis was M. A. Lazarevsky and B. A. Dospekhov methods. The calculation of economic efficiency was carried out on the basis of actual costs associated with technological operations, fertilization, irrigation, protective measures, collection of main and additional products. Results. The most cost-effective is the combined use of soluble foliar fertilizers Plantafol and Boroplus on grape plantations. The Rizamat variety was distinguished. Conclusions. The economic efficiency of the soluble foliar fertilizers application on grape plantations on average for 2015–2017 is the most significant in all three varieties Kodryanka, Rizamat and Moskovsky during combined application of fertilizers, especially in the Rizamat variety, when growing and receiving grape products of which the cost price decreased by 24.6 %, reaching a minimum value of 14947.4 rubles/t, profitability increased to 234.5 %, and the payback up to 3.35 rubles/rubles.