Efficiency of foliar additional fertilizing of corn at different periods of application

The studies were carried out on ordinary carbonate chernozem in the zone of sufficient moistening in the Stavropol region in 2021–2023. The effectiveness of foliar additional fertilizing with fertilizer Batr Zinc (1.0 l/ha) was studied on corn hybrids Mashuk 220 MV and Mashuk 355 MV in the 5 and 8 leaves phases. Additional fertilizing was carried out on a background without any mineral fertilizing, as well as backgrounds of nitrogen (N₃₀) and complete mineral fertilizing (N₃₀P₃₀K₃₀). Data were obtained on the terms influence of foliar additional fertilizing with fertilizer Batr Zinc on the corn plants height, the yield of green mass and grain, and crop structure elements. Foliar additional fertilizing of corn in 5 or 8 leaves phases with fertilizer Batr Zinc at a dose of 1.0 l/ha had a positive effect on plants growth. Without the use of mineral fertilizers in the flowering phase, the plants height of the hybrid Mashuk 220 MV increased on average for 2021–2023 by 14 and 16 cm, hybrid Mashuk 355 MV – by 17 and 23 cm. On average, over 3 years without the use of mineral fertilizers, corn fertilizing in the phases of 5 or 8 leaves with fertilizer Batr Zinc increased the yield of green mass of the hybrid Mashuk 220 MV by 5.2 and 6.0 t/ha (15.1 and 17. 4 %), hybrid Mashuk 355 MV – by 7.7 and 6.8 t/ha (23.2 and 20.5 %). Depending on the fertilizing terms, the grain yield of the hybrid Mashuk 220 MV increased by 0.59 and 0.63 t/ha (9.2 and 9.9 %), of the hybrid Mashuk 355 MV – by 0.83 and 0.74 t/ha (12.9 and 11.5 %). There was no significant difference in the yield of green mass and grain between the fertilizing terms. Against the background of mineral fertilizers, foliar additional fertilizing with the agrochemical Batr Zinc was ineffective.