Scientific publications

The dynamics of some parameters of the photosynthetic apparatus (PSA) activity of winter wheat seedlings during hardening at a temperature of 4 °С were studied. It was shown that first hours of cooling were the phase of peculiar functional «reset» of the plant organism to the new temperature conditions. In this period, we observed some decrease in PSA activity, cessation of leaf linear growth, and an adaptive increase in non-photochemical quenching of chlorophyll fluorescence. Then (1–4 days), cold resistance of leaf cells attained the highest level, the rate of photosynthesis and electron transport stabilized, chlorophyll content in the light-harvesting complex (LHC) increased, and plant growth resumed. The final phase of adaptation (4–7 days) featured not only constant tolerance level, but also new functional organization of PSA which allowed the plants to successfully survive low temperature.