Funding for this research was provided by:
National Natural Science Foundation of China (nos. 31170198, nos.31530003)
Article History
Received: 18 December 2017
Accepted: 22 November 2018
First Online: 7 December 2018
Ethics approval and consent to participate
: Parental plant materials used in this study were collected in field with necessary permissions from local authorities of Forest Department. All seeds and hybrid plants used in this study were produced by the authors in the glasshouse of Institute of Botany, Chinese Academy of Sciences (IBCAS), Beijing, China.
: Not applicable.
: The authors declare that they have no competing interests.
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