Comparative Analysis of Transcriptomes of Diploid and Tetraploid under Drought Stress.

is a species of bioenergy crop unique to China. It is widely distributed in the south of China with high resistance to drought and salt stress. To date, the molecular mechanism of the adaption to drought stress in is little known. In this study, RNA-seq technology was employed to analyze the transcriptome changes of diploid and tetraploid after drought treatment. It was found that the number of differentially expressed genes in diploid was much higher than tetraploid, whereas the tetraploid may require fewer transcriptional changes. While the transcriptional changes in drought-tolerant tetraploid are less than that of diploid, more known drought-tolerant pathways were significantly enriched than drought-sensitive diploid . In addition, many drought-tolerance-related genes were constitutively and highly expressed in tetraploid under either normal condition or drought stress. These results together demonstrated that drought-tolerant tetraploid , on the one hand, may preadapt to drought by constitutively overexpressing a series of drought-tolerant genes and, on the other hand, may adapt to drought by actively inducing other drought-tolerant-related pathways. Overall, this study could deepen our understanding of the molecular mechanism of drought-tolerance in bioenergy plants.