Net photosynthetic productivity of maize hybrids depending on plant density and micronutrients

Abstract

The efficiency of the functioning of the photosynthetic apparatus is determined not only by the leaf area and the photosynthetic potential of the crops. An important indicator is also the net photosynthetic productivity, which reflects the increase in dry biomass per unit of time per unit of leaf area. This parameter indicates how many grams of dry matter are produced per 1 m² of leaf surface per day and allows for a more accurate assessment of the efficiency of assimilative surface utilization during the growth and development of plants. The impact of plant density and foliar micronutrient fertilization on the net photosynthetic productivity of maize hybrids of different FAO groups was studied during 2022-2024 in a field experiment conducted at LLC AF "Agrotechnologia-Plus" in the Kropyvnytskyi district of Kirovohrad region on typical low-humus chernozem. Net photosynthetic productivity was determined during the interphase period BBCH 17-BBCH 65. The net photosynthetic productivity during the BBCH 17 – BBCH 65 interstage period ranged from 4.60 to 7.06 g/m² per day. The highest values of net photosynthetic productivity were recorded for the hybrids DKC 4391 and DKC 4712 (6.30 g/m²/day), plant densities of 60-65 thousand plants/ha (6.41-6.44 g/m²/day), and foliar application of the micronutrient fertilizer Amino Ultra Corn (6.70 g/m²/day).