Photosynthetic activity of corn in connection with leaf feeding with organomineral fertilizers

The aim of the research is to identify the effect of leaf fertilization with organomineral fertilizers on the photosynthetic activity of corn in the conditions of gray forest soils of the Central Chernozem region. Field experiments were conducted in 2017-2020 at the experimental field of the "Integration" of the Orel district of the Orel region. The soils of the experimental field are gray forest, medium loamy. The degree of saturation with bases is 93%; the thickness of the humus horizon is 25-30 cm, the content of humus in the arable layer is 4.7%, mobile phosphorus P2O5 is 17 mg/100 g, exchangeable potassium K2O is 9.6 mg/100 g of absolutely dry soil; pHcl is 5.2. Agrotechnical techniques are generally accepted in the region for fodder and silage crops. The predecessor is annual herbs. Cleaning was carried out on plots in the phase of full ripeness. Arrangement of the plots is systematic. Number of replication is threefold. The crop production area of the plots is 53.2 m2. The discount area is 50.4 m2. The object of research was 2 hybrids of corn of different ripeness groups. Foliar fertilizing was carried out with complex organomineral fertilizers Megamix-N-10 and Aminocate 30% in the phase of 3-4 leaves and in the phase of 5-7 corn leaves with norms of 10, 15 and 20 kg / ha. The varietal specificity of maize hybrids in relation to leaf fertilization with organomineral fertilizers was revealed. The early-maturing hybrid Ross-14 SV under the influence of the fertilizer Megamix-N-10 actively increases the leaf area up to and including the phase of the appearing of panicles. In the middle-early EU Hubble hybrid, the leaf surface area increases almost uniformly during the entire growing season. The variation of the indicators "leaf surface area" and photosynthetic potential " during the growing season of maize hybrids of different maturation periods, as a whole, practically did not affect the net productivity of photosynthesis (NPF) due to the use of different types of fertilizers as leaf-feeding dressing. Thus, the NPF of the early-maturing hybrid using Megamix-N-10 and Aminocate 30% was 9.89 and 10.13 g/m2 days, respectively, and the average - 10.06 and 10.22, respectively. The optimal dose of organomineral fertilizers for leaf feeding is 20 kg / ha.