Activity of reactions of the light phase of leaf photosynthesis in buckwheat varieties of different breeding periods

Photosynthesis includes two phases - light and dark, which take place in the chloroplasts ofthe cell. In the light phase, light quanta are captured and their energy is converted intomacroenergetic and reducing compounds, which are necessary, in particular, for theassimilation of CO 2 and the formation of organic substances in the dark phase. The genotypic features of these processes in many agricultural crops, including buckwheat, whichis in demand on the world food market, are poorly or almost not studied. We have carried outlong-term studies on a large set of buckwheat varieties to identify hereditary features of themanifestation of light reactions of leaf photosynthesis. Objectives - to show the genotypicpolymorphism of indicators of the activity of reactions of the light phase of photosynthesisand the possibility of their use in crop breeding. It has been established that the activities oflight reactions of leaf photosynthesis in buckwheat plants are characterized by widepolymorphism and high genotypic conditionality. The quantum yield of chlorophyllfluorescence in leaves of experimental crop varieties changed during the years of researchfrom 0.223 to 0.336 rel. units The values of the electron transport chain of the leafphotosystem II varied in buckwheat varieties during the years of research in the range from93.3 to 140.9 rel. units The interval of genotypic variation in the values of photochemicalquenching of chlorophyll fluorescence in leaves ranged from 0.546 to 0.922 rel. units Amongthe studied cultivars, the Dasha and Temp cultivars and promising accessions P 1 and P 47are characterized by the highest activity of the quantum yield of chlorophyll fluorescence inleaves. Whereas the cultivars Diana and Ballada are distinguished by the highest activity ofphotochemical quenching of chlorophyll fluorescence.