Dependence of the intensity of the visible photosynthesis, temperature and transpiration of leaves of Arbutus andrachne L. on some environmental factors

Abstract

The dependence of the intensity of visible photosynthesis, temperature and transpiration of Arbutus andrachne L. leaf on some environmental factors, and their changes in the spring growing season on the Southern Coast of the Crimea. The obtained data make it possible to interpret the rate of photosynthesis as a potential ecological and physiological characteristic of this species. This makes it possible to compare different plant species that grow in similar conditions, according to indicators measured using the same technique. A. andrachne L. has a relatively high potential for photosynthesis acclimatization to elevated temperatures. At leaf temperature above optimum, the intensity of photosynthesis drops sharply, and its critical value is 32°C. Analysis of the results shows that the optimal value of the net photosynthesis of Pn in May compared with April increased by 35% and reached the value of 12-17.5 µmol/m²s, while the optimal value of the transpiration intensity of El during the same time increased by 138%, the Tair temperature - 56%, the lack of humidity Da - has not changed, the leaf temperature increased by Tl - 21% and the illumination of the illumination PAR- 50%.