Overexpression of Chrysanthemum lavandulifolium CBF1 gene enhances resistance to drought and salt tolerance in Arabidopsis thaliana

The C-repeat-binding-factor (CBF) is a class of plant-specific transcription factors with multiple functions. In the present study, the ClCBF1 gene isolated from Chrysanthemum lavandulifolium was constructed using the plant expression vector pBI121, and Agrobacterium-mediated was used to genetically transform Arabidopsis thaliana. Four transgenic lines were obtained. After resistance screening and RT-PCR, three transgenic lines with high expression were studied. The results showed that the seed germination rate and root length of transgenic A. thaliana were 2.0 times and 1.2 times higher than that of wild type in 150 mmol·L-1 mannitol medium, respectively, whereas the seed germination rate and root length of transgenic A. thaliana were 1.1 times and 1.4 times higher than that of wild type in 150 mmol·L-1 NaCl medium, respectively. Under drought and salt stress, the survival rate of transgenic A. thaliana seedlings was higher than that of the wild type seedlings, and the activity of superoxide dismutase (SOD) and peroxidase (POD) was significantly higher than that of the wild type. The MDA content and relative conductivity were significantly lower in transgenic A. thaliana seedlings than that in wild type seedlings (P<0.05). These results indicate that the ClCBF1 gene plays a role in A. thaliana under drought and salt stressconditions.