Genotypic features of photosynthetic activity of leaves of spring wheat plants in connection with the selection of new types of varieties

Abstract

The article is devoted to the results of research on species and genotypic features of photosynthetic activity in spring wheat plants in connection with the creation of varieties that form a high, stable, high-quality and environmentally safe crop due to the effective use of renewable natural energy of the sun by photosynthesis. It was found that the intensity of leaf photosynthesis in a culture significantly depends on the hereditary characteristics of plants, the growth phase, location, time of day, and lighting conditions. The range of genotypic changes in the trait in 2017 was 9.65-16.35, in 2018 – 9.55 – 21.42, in 2019 – 8.73 – 17.15 ?mol CO2/m2s. In the phase of tillering and milk ripeness in crop varieties, the most significant manifestation of CO2 gas exchange activity by leaves is noted. In the tillering phase, varieties with high photosynthesis intensity were 30% superior, and in the milk ripeness phase, varieties with low photosynthesis intensity were 31% superior. The most active is the absorption of CO2 molecules from the air by the flag leaf of plants. During the period of grain formation, the intensity of photosynthesis exceeded the pre – flagged leaf by an average of 1.6 times, and the lower-lying leaf by 2.8 times. This shows a high dependence of the intensity of leaf photosynthesis on the light regime. When the light intensity increased from 300 to 1000 ?mol/m2s, the photosynthesis intensity of the flag leaf of spring wheat plants increased by an average of 102 %, and above 1000 ?mol/m2sby 14 %. Of the studied varieties, the most responsive to the conditions of insolation is Volnodonskaya, Lyubava, Chernozem-Uralskaya, in which the full light saturation of photosynthesis was observed at 1800 ?mol/m2s. The correlation coefficient between the intensity of photosynthesis and illumination was 0.93.