In the Central Ciscaucasia, including North Ossetia-Alania, in recent years, new fast-growing, immune, highly-productive varieties of apple trees of an intensive type have become widespread. The effectiveness of the use of fertilizers for growing new varieties of apple trees has not been studied. In this regard, a study was made of the responsiveness of three apple varieties to mineral and organic fertilizers (manure) and their combination. The apple orchard was studied on leached chernozem, covered by pebble from a depth of 50 cm and having a wash water regime. As a result of research, it was found that the use of mineral and organic fertilizers in this type of garden is an effective agrotechnological technique. The use of mineral and organic fertilizers increases the productivity of the fruits of the varieties Aidored, Florina and Stark-Nart by 20.0–130.4 % compared with non-fertilized control. The Florina variety was the most fruitful. Significantly less productive is the Aydored variety and especially Stark-Nart. In the control, respectively, Florin’s variety – 22.0 t/ha, Aidored – 12.5 t/ha and Stark-Nart – 11.5 t/ha. Of the fertilized options, the best in all three varieties was N150P150К150: productivity was 40.5, 28.5, and 26.5 t/ha, respectively. The fertilizers under study affected the quality indicators of fruits in different ways. For Aidored variety, there is a tendency toward a decrease in the dry matter content and fruit acidity as the level of mineral nutrition increases, while the content of sugar, vitamin C, P-active substances, sugar-acid index and pectin substances increase. According to these indicators, N150P150К150 stands out as the best of the fertilized options. In relation to the Florin and Stark-Nart varieties, it should be pointed out that the patterns of action of fertilizers on the quality of fruits noted for the Aidored variety are identical, although the quantitative indicators are not the same. In particular, it can be noted that in terms of sugar content, Stark-Nart is inferior to two other varieties. And in terms of acidity, Florin is an advantage (the fruits are less acidic). Vitamin C is more in the fruits of the Aidored variety (9.3 mg / 100 g in the control), Florin is in second place, and Stark-Nart is in third (in the control of 8.0 and 7.1, respectively).

This article presents the results of studying the dynamics of the nutritive regime for leached black soil during the vegetation period of apple trees depending on the dosage and application times of compound fertilizers, as well as combinations of organic and mineral fertilizers. We detected a positive influence of fertilizers on the accumulation of liable forms of nitrogen, phosphorus, and potassium in the soil of the fruit orchard. The highest average content of ammonia absorbed during vegetation was observed in section N180P180K180 – 40.6 mg/kg, which was 10.4 mg/kg higher than in the unfertilized ref-erence section. The content of nitrates in the reference section was 8.9 mg/kg of the soil. The application of N60P60K60 increased their content by 2.3 mg/kg (25.8%), N90P90K90 - by 3.1 mg/kg (34.8%), N120P120K120 - by 4.8 mg/kg (53.9%). The application of mineral fertilizers at various rates had a significant impact on the content of liable phosphorus in the 0-40 cm layer of soil: its average content per vegetation period was 101.8 mg/kg of the soil for section N60P60K60 and 129,1 mg/kg for section N150P150K150. The content dynamics for exchangeable potassium in the fruit orchard soil was at the maximum at the beginning of the vegetation period and the minimum during fruit formation. Later on, the content increased during the harvesting stage but it was lower than the original level. The highest average content of exchange-able potassium per vegetation period was observed in section N150P150K150 – 184 mg/kg, which was 44 mg/kg higher than in the reference section. Out of the two sections treated with manure, the Manure 20 t/ha+N30P70 (with NPK reaching up to 120 kg/ha) section was deemed more efficient. The content of exchangeable potassium in it exceeded the reference section by 41 mg/kg.

The study revealed optimum doses, NPK combinations, terms and methods of fertilizer application, which provides for highly efficient use of nutrients thus maintaining the fertility of soils, high efficiency and high quality of winter wheat grains. The application of some mineral fertilizers was followed by some decrease (trend) of humus content in relation to control samples. The option manure+NPK was characterized by relative stabilization of humus condition of soil, and concerning the average humus content this option exceeded the control one by 0.32 %. Fertilizers clearly improved the nutrient status of leached chernozem under winter wheat enriching its 0–40 cm layer with mobile nitrogen (NН4+ and NO3−), phosphorus and potassium respectively by 6.0–9.2; 3.2–9.4; 9.3–36.7 and 21.5–32.8 mg/kg of soil on average per vegetation. Options with high doses of mineral fertilizers were characterized by the largest content. The application of fertilizers under winter wheat in N50−150P40−120K40−120 doses increased grain yield from 0.22 to 2.32 t/ha (6.9–72.5 %). The estimated option was the best.

A hybrid Svyatogor F1 of Dutch breeding was grown in a winter greenhouse for three turns. Studies have shown that pre-sowing seed soaking treatment and foliar top dressing of plants with potassium humate did not affect germination, but positively affected plant growth, except for lithium carbon dioxide. For potassium humate and PABA, the leaf area increased, while for lithium it decreased. Micro fertilizers, except lithium, had a positive effect on the formation of fruits, their weight and yield. The largest yield of cucumbers was obtained by PABA and potassium humate mixed with other trace elements: 33.63 and 34.0 kg/m2 with a control indicator of 30.75 kg/m2. One foliage fertilization with micro fertilizers also had a positive effect: in terms of yield, the variant of a mixture of all fertilizers was in the first place - 34.75, the PABA with a yield of 33.93 kg/m2 was in the second place, and 30.97 kg/m2 were in the control. Lithium had a retarding effect on all indicators.