Activated expression of EsHD1 enhances drought tolerance in tobacco plants via mitigation of reactive oxygen species-mediated membrane damage

Abstract

It is well documented that the homeodomain-leucine zipper (HD-Zip) transcription factors play diverse roles during plant growth and development. The Class I HD-Zip genes are shown to be involved in the regulation of abiotic stress responses and tolerance. Herein, a novel Class I HD-Zip gene, EsHD1, was isolated from Eutrema salsugineum, and an investigation was performed of its physiological functions in response to drought stress. The analyses of gene expression profiles revealed that the EsHD1 transcripts quickly accumulated upon exposure to various abiotic stress conditions or abscisic acid treatments. Furthermore, the overexpression of EsHD1 in tobacco plants conferred improved tolerance to drought stress. The EsHD1-overexpressing lines had lower levels of reactive oxygen species (ROS), ion leakage, and malondialdehyde, but they manifested higher activities of antioxidant enzymes and the transcription of pathogenic-related genes as compared to wild-type plants under drought stress conditions. Therefore, our findings demonstrated that EsHD1 positively regulated plant drought tolerance via alleviation of ROS-mediated membrane damage.

Rhizobacterial Strain Bacillus megaterium BOFC15 Induces Cellular Polyamine Changes that Improve Plant Growth and Drought Resistance

“…The photosynthetic rates (Pn) of both the control and inoculated plants markedly dropped because of drought stress, but the value of Pn was considerably higher in the inoculated plants than in the control plants ( Figure 6 a). The chlorophyll content has been taken as a typical indicator that evaluates the ability of plants to tolerate abiotic stress [ 28 ]. Our data showed that the amount of chlorophyll displayed evident alterations with a gradual decrease accompanied by the time-delay of drought treatments ( Figure 6 b).…”