Funding for this research was provided by:
National Natural Science Foundation of China (31672458)
National Key R&D Program of China (2016YFD0501409-02)
Fundamental Research Funds for Central Non-profit Scientific Institution (1610382016004)
Elite Youth Program of Chinese Academy of Agricultural Sciences (n/a)
Text and Data Mining valid from 2019-01-09
Received: 30 September 2018
Accepted: 27 December 2018
First Online: 9 January 2019
: Ethics approval was not needed for the study.
: Not applicable..
: The authors declare that they have no competing interests.
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