Funding for this research was provided by:
National Natural Science Foundation of China (No. 31770712)
Fundamental Research Funds for the Central Universities (2572015EA03)
Text and Data Mining valid from 2018-12-01
Received: 4 May 2018
Accepted: 30 November 2018
First Online: 20 December 2018
Ethics approval and consent to participate
: The <i>Betula platyphylla</i> materials used in the study were preserved in the State Key Laboratory of Tree Genetics and Breeding and were planted on the campus of Northeast Forestry University (latitude 45°42′57.58″N, longitude 126°37′44.41″E). As researches of the laboratory, we are allowed to use these materials for research. Samplings of these materials were performed in compliance with institutional, national, and international guidelines.
: Not applicable.
: The authors declare that they have no competing interests.
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