Флуоресценция хлорофилла кукурузы и механизм повышения ее урожайности при внесении минеральных удобрений

Abstract

Abstract. In previously conducted experiments it was found that the improvement of mineral nutrition of plants contributes to the increase of net productivity of photosynthesis. However, the methods used to determine this indicator are not based on direct determination of the values of photosynthetic indicators, but on calculations based on taking into account the area of plant leaves and the formation of dry matter. The aim of the work was to directly determine the effect of fertilizer application on chlorophyll fluorescence and photosynthetic activity of plants. Research methodology. To directly assess the effect of mineral fertilizers on the efficiency of the photosynthetic apparatus, the RAM-250 fluorometer was used. Observations were made on corn leaves. The fluorescence was measured six times over. Results. It was found that the application of mineral fertilizers slightly changed the intensity of photosynthesis in terms of Fv/Fm. So the average value of Fv/Fm increased from 0.763 for the background without fertilizers to 0.775 Rel. units for the fertilized background. Dispersion analysis showed that these changes are insignificant. But, at the same time, when applying mineral fertilizers, the yield of green corn mass increased from 20.5 t/ha to 24.0 t/ha, i. e. by 17 %, and the collection of dry matter from 5.5 t/ha to 6.7 t/ha, or by 22 %. At the same time, a corresponding 25 % increase in the size of the root system of maize plants was observed. Thus, it was found that the introduction of mineral fertilizers increasing the yield of cultivated plants is not necessarily accompanied by an increase in the activity of their photosynthetic apparatus. This is the novelty of the research. The explanation of the mechanism of increasing the productivity of maize plants when applying mineral fertilizers is given.