Use of nitrogen leaf fertilizing to increase the yield of tomatoes in the Astrakhan Region

The possibility of improving the zonal technology of cultivating tomatoes in the open ground using leaf fertilizing with KCl and KNO₃ aimed at increasing yields during irrigation in the conditions of the north of the Astrakhan region was investigated. Field experiments were conducted on an experimental irrigated land use site of the Caspian Agrarian Federal Scientific Center of the Russian Academy of Sciences in the period from 2021 to 2023. The scientific novelty of the study consisted in the theoretical and practical justification of the use of leaf fertilizers with KCl and KNO₃ in the cultivation of vegetable crops aimed at the formation of highly productive marketable products. A comparative analysis of different doses of fertilizers was carried out with the selection of the most promising option. Three-year studies have found that the use of KCl of 0.5% fertilizer on the 30–40th day after planting seedlings (flowering phase), on 50th and 60th day after planting gave a significant increase in yield relative to the control. According to the results of the analysis, on average for 5 croppings, the background + 3 KCl treatment option (concentration 0.5%) was identified as the one resulting in the highest yield – 131 t/ha. This option differed significantly from both the control and other studied options. The increase in yield relative to the control was 4.08 t/ha or 3.2%.