Funding for this research was provided by:
the Natural Science Foundation of JiangSu Province (BK20150879)
the ‘Twelfth Five-Year’ National Science and Technology Support Program (2012BAD01B03)
the China Postdoctoral Science Foundation Grant (2014T70530)
Text and Data Mining valid from 2018-05-29
Received: 15 August 2017
Accepted: 22 May 2018
First Online: 29 May 2018
Ethics approval and consent to participate
: All poplar materials used in the study were the registered cultivars in International Poplar Commission of the Food and Agriculture Organization (IPC-FAO, ExternalRef removed). As researchers of Nanjing Forestry University, we are allowed to use these poplar materials for research in China. Sampling of these poplar materials were performed in compliance with institutional, national, and international guidelines.
: The authors declare that they have no competing interests.
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