The effect of drought on the expression of stress resistance genes in perspective forms of birch

Abstract

Abstract Drought stress greatly limits distribution of forest-forming species, in particular, birch. The actual task is to identify resistance mechanisms in order to select perspective genotypes for further reproduction. The purpose of this work was to identify drought-tolerant genotypes of silver birch (B. pendula Roth.), downy birch (B. pubescens Ehrh.) and their hybrids based on the analysis of drought tolerance. We studied the expression of genes encoding proteins of metabolic pathways that are activated in response to abiotic stress (phenylpropanoid way) associated with the pathogenesis of proteins (PR1 and PR10), transcription factors (DREB2), and proteins of late embryogenesis (LEA). As a result of the effects of drought, a significant increase in expression was detected for the PAL, PR-1, PR-10, and DREB2 genes in the analyzed samples; at the same time, expression changes were revealed for the LEA8 gene for two out of ten genotypes. Birch samples 29-58 and 233 was selected as most stable showing adaptive response for all genes analyzed. Analyzed genes can be recommended as markers for assessing drought resistance of other woody plant species.