Drought stress response in two Algerian durum wheat genotypes: physiological and molecular analysis of two stress responsive genes

Drought is a worldwide constrains affecting plant growth and productivity. This problem is becoming a more serious threat to the high-quality crop production within a changing climate. Drought triggers a variety of plant responses by modifying a range of genes expression. The aim of this work was to study two durum wheat genotypes (Waha and Beliouni) response to drought stress at physiological and molecular level, by focusing on two stress responsive genes (Dehydrin and Aquaporin). At the physiological level, the characterization of genotypes response was performed by determination of germination rate (GT), relative water content (RWC), leaf temperature (LT) stomatal conductance (gs), chlorophyll content (SPAD index) and electrolyte leakage (EL). Expression level of an aquaporin gene (TdPIP2,1) and a dehydrin gene (DHN5) was also analyzed in different plant tissues under different drought stress conditions . The DHN5 gene is not expressed in the well watered plants but only in the stressed plants, while the TdPIP2,1 is expressed in both with more higher level in stressed tissues. Moreover, the transcript level of the two genes was more accumulated in the tolerant genotype (B) than the more sensitive one (W). These results confirm our physiological data. Identification of a possible connection between activated stress responsive genes can be useful by providing a starting point to further elaborate biotechnology-based approaches.