The effect of fertilizers and pre-sowing treatment of seeds and crops on the photosynthetic activity of spring wheat crops in the conditions of the Kama region of the Republic of Tatarstan

The research was carried out in order to study the peculiarities of the effect of mineral fertilizers and concentrated organomineral complex liquid fertilizers on the photosynthetic activity of spring soft wheat crops of the Ulyanovsk 105 variety. The work was carried out in 2021-2023 in the Kama region of the Republic of Tatarstan. The soil of the experimental site is light gray forest, medium loamy. Agrochemical indicators: the content of humus according to Tyurin was 1.9%, mobile phosphorus and potassium according to Kirsanov in the modification of TSINAO – 145 mg/kg and 127 mg/kg, respectively, soil acidity – 6.4 pH. The doses of mineral fertilizers were determined by the calculation and balance method for grain yield of 3 t/ha, which amounted to N106P27K41. In addition to mineral fertilizers, the effect of concentrated organomineral complex liquid fertilizers Batr Gum, Batr MaX produced by Service Agro was evaluated. The use of calculated doses of mineral fertilizers significantly increased the leaf surface area compared to the control. The maximum leaf surface area over an average of three years was observed in the earing phase and reached in the NPK variant for 3 t/ha of grain + Batr (0.5 l/t +1 l/ha +1 l/ha) - 34.06 thousand m2/ha. The highest value of the LFP for the growing season of spring wheat in 2023 was obtained when applying mineral fertilizers and using Batr Gum, Batr MaX – 1491 thousand m2 / day per 1 hectare. The indicator of the net productivity of photosynthesis is very dynamic. It depends on both the environmental conditions and the condition of the plants themselves, primarily on the assimilation work of the leaves and their surface area. When NPK was applied in order to obtain 3 tons/ha of grain, the leaf area increased, and the weighted average for the vegetation of the NPF decreased by 0.8...0.4 g/m2 per day over the years of research. The highest increase in the yield of spring wheat of the Ulyanovsk 105 variety on average for 2021-2023 was with the use of mineral fertilizers, Batr Gum and Batr MaX preparations amounting to 1.39 t/ha.