Photosynthetic activity of winter wheat depending on fertilization and lime application on sod-podzolic soil in the conditions of Western Polissia

Topicality. Increasing the productivity of crop photosynthesis, i.e. the amount of organic matter synthesised per unit of leaf surface in a day, is an essential condition for high crop yields. The area of the leaf surface depends on the biometric parameters of the plant, the nutritional regime, as well as the duration of leaf activity, which significantly affects the accumulation of organic matter. Purpose. To identify the influence of mineral nutrition optimization and chemical amelioration on the formation of leaf surface area, photosynthetic potential, and net photosynthetic productivity in the main development stages of winter wheat grown on sod-podzolic soil in the conditions of the Western Polissia. Methods. Field experiment, calculation and statistical methods. Results. In particular, with the application of dolomite powder at a dose of 1.0 Hh and different fertilisation variants, the leaf surface area of plants increased from 1.5 ths. m2/ha to 4.12– 6.99 ths. m2/ha in the tillering stage, from 4.07 ths. m2/ha to 14.16–21.34 ths. m2/ha in the stem elongation stage, and from 2.59 ths. m2/ha to 5.33–9.49 ths. m2/ha in the heading stage, respectively, compared to the control (without fertilisation). It is noted over the years of research that the application of mineral fertilisers on the background of liming increased the indicator of photosynthetic potential by 2.6–3.5 times compared to non-fertilised one, and the net productivity of photosynthesis increased by 15.4–21.3 % compared to the control. Conclusions. The largest indicators of leaf surface area, photosynthetic potential, and net photosynthetic productivity in the tillering, stem elongation and heading stages were formed by application of N150Р50К125 + S40 + microfertilizer (two applications). The highest photosynthetic activity of winter wheat plants were noted in the stem elongation stage. Key words: winter wheat, fertilization, amelioration, leaf surface area, photosynthetic potential, net photosynthetic productivity