The influence of temperature, moistening and growth phase on the rate of photosynthesis of leaflets and stipules of pea plants

The influence of temperature, moistening and growth phase on the rate of photosynthesis of leaflets and stipules of pea plants ( Pisum sativum L. ) is estimated in the article. It is stated that its magnitude varies significantly from the weather conditions during the growing season. In the dry years of 2010 and 2011 the rate of photosynthesis of leaves was 8.38 and 8.23 μmol CO2 / m2s on average during the growing season respectively, and it was 15% lower, compared to the favourable weather in 2012 - 9.79 μmol CO2 / m2s. In ontogenesis, the rate of photosynthesis increased sharply during the generative development period, when plants needed maximum of assimilates for the formation of fruits and seeds. It was noted that assimilation organs reached their maximum intensity of photosynthesis in the phase of a flat bean, and they decreased as the seeds ripened. At the same time, it was established that the rate of photosynthesis of leaflets in an industrial crop is on average 10% higher in comparison with stipules, which, apparently, is associated with better insolation. The absolute value of the intensity of photosynthesis of both plant organs on average for the vegetation was lower by 61%, compared to field conditions. A weak positive correlation is revealed between the intensity of photosynthesis of the photoassimilating bodies and productivity (r = + 0.33 …+ 0.56).