Funding for this research was provided by:
Ministry of Science and Technology of the People's Republic of China (2016YFD0100501)
National Transgenic Major Program of China (2016ZX08001-002)
Chongqing Science and Technology Innovation Special Project (cstc2016shms-ztzx80007, cstc2017shms-xdny80057)
Chongqing Research Program of Basic Research and Frontier Technology (cstc2015jcyjA80008)
Fundamental Research Funds for the Central Universities (XDJK2015D031)
Received: 29 October 2017
Accepted: 27 September 2018
First Online: 9 November 2018
Ethics approval and consent to participate
: The field work in our study was approved by local legislation.
: Not applicable.
: The authors declare that they have no competing interests.
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