Abstract. Relevance. Currently, in grape nursery breeding, pre-plantng treatment of the seedlings (in own-root culture) and the basal part of the grafting (with grafted culture) is used to increase the yield of seedlings. There is very little data on the use of modern complex fertilizers during stratification and at nursery in the production of grafted planting material, which reflects the relevance of our research. The purpose of the study is. the exploring of the foliar application of the agrochemicals “Fertigrain Foliar Plus” on the intensity of the development of the leaf surfase of the Siberian grape variety. Methods. The methods of setting up the experience and analyzing the data obtained were used in the work, which are generally accepted in the practice of nursery breeding. Results. With additional application of “Fertigrain Foliar Plus”, a significant increase in biometric indicators was observed, namely: the total length from 84 cm (c) to 150.7–171.7 cm; shoot maturation from 25.7 % (c) to 45.4–48.0 %, shoot diameter from 5.6 mm (c) to 8.3–9.0 mm and leaf surface area with 645.1 cm2 (c) to 1995.8–3382.0 cm2. With an increase in the number of treatments, the ratio of the number of leaves by fractions changed in the direction of increasing their size, namely (< 5; 5.1–10; > 10 cm): in the control – 1 : 5 : 0; with double processing – 1 : 12 : 4; with triple treatment – 1 : 9 : 8; with quadruple treatment – 1 : 6 : 12. With an increase in the number of treatment from 2 to 4 times, there was no increase in the number of leaves, however, the average leaf size increased significantly from 8.5 to 10.5 cm. Scientific novelty. For the first time in the conditions of the Rostov region, a modern growth stimulator “Fertigrain Foliar Plus” was studied during the foliar treatment of grafted grape seedlings on nursery-garden. Practical significance. The results of the research can be used in the practice of grape nursery to improve the adaptation of seedlings on nursery-garden, stimulate the development of the leaf area and the intensity of ripening, which is especially important for growing varieties with weak ripening.
