Fertigation efficiency estimation in cultivating apple varieties in the intensive type garden of the Central Ciscaucasia

The purpose of research is to evaluate the effectiveness of the methods of watering and feeding apple trees in an intensive type orchard in the conditions of the Central Ciscaucasia. To achieve this goal, experiments were carried out on the territory of the training and experimental station of the Stavropol State Agrarian University to study the effectiveness of fertigation and drip irrigation relative to control without the use of irrigation and fertilizer. The apple varieties Golden Delicious, Braeburn, Gala, Champion and Jeromini were the object of research. Accounts were taken of the influence of the analyzed factors on the average growth of annual shoots, the average weight of fruits and the yield of the apple varieties under consideration. On average, for varieties on the studied backgrounds, there was a significant increase in the average length of the growth of branches relative to the control by 12.8-23.1 cm, and against the background of fertigation, a significant advantage was also noted relative to the variant with irrigation without fertilizer - by 10.3 cm. Of the considered apple varieties, the most restrained growth of branches was observed in the varieties Braeburn and Champion, which amounted to 19.9-21.9 cm in the experiment. Accounting for the average fruit weight in the experiment showed that against the background of the considered irrigation options, there was a significant increase in the average fruit weight relative to the control by 21.7-29.7 g. The maximum average fruit weight in the experiment was observed against the background of fertigation. The highest indicator was observed in the Champion variety, which significantly exceeded the results of the other varieties in the experiment by 24.3-34.7 g. The harvest records showed a similar picture. Both irrigated options showed a significant increase relative to the control by 2.5-4.5 t/ha, and when comparing the studied options with each other, a significant advantage of fertigation is noted relative to the option with irrigation without fertilizer by 2.0 t/ha. The maximum yield in the experiment was in the Champion variety with fertigation, which exceeded the performance of other options by 2.2-15.6 t/ha.