The Increase in Adaptive Capacity to High Illumination of Barley Plants Colonized by Rhizobacteria P. putida BS3701.

The effect of the colonization of barley plants (Hordeum vulgare L.) by the associative microorganisms Pseudomonas putida BS3701 on the adaptation of the photosynthetic apparatus to high light intensity was studied. A number of differences were found in the functioning and structure of the photosynthetic apparatus of the control plants and plants colonized by P. putida BS3701 grown at 100 µmol quanta/m2 s. The barley plants colonized by P. putida BS3701 were shown to have an increased resistance to high light intensity (1000 µmol quanta/m2 s) when compared to the control plants. It was established that the adaptive decrease in the PSII antenna size was characterized by the same molecular mechanism in both the control plants and plants colonized by P. putida ВS3701. However, the decrease in PSII antenna size was more pronounced in plants colonized by P. putida ВS3701. It can be assumed that this might be the cause of more efficient protection of the photosynthetic apparatus of plants colonized by P. putida BS3701 against photoinhibition under high illumination. [ABSTRACT FROM AUTHOR]