National Natural Science Foundation of ChinaNational Natural Science Foundation of China (NSFC) [31672457, 31772642]; Ministry of Agriculture of the People's Republic of ChinaMinistry of Agriculture, China [2015-Z64, 2016-X47]; Hunan Provincial Science and Technology Department [2016NK2101, 2017NK2322, 2016WK2008, 2016TP2005]