This work was financially supported by the National Natural Science Foundation of China (31900087), the Project of International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province (2018WK4008), Ministry of Science and Technology of the People's Republic of China (2017YFE0108100), Outstanding Youth Project of Hunan Provincial Education Department (18B169) and Aid Program for Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Province (2019-379-9).