Genetic diversity
Cerasus serrulata is a widely distributed species in China of the genus Cerasus and is involved in the subtropical and temperate monsoon climate zones. Both cpDNA (H d=0.828,P i=1.490) and ITS (R d=0.673, P i= 2.521) analysis proved a high genetic diversity of C. serrulata , higher than wild C. pseudocerasus (cpDNA: h =0.557, π =2.09) (Chen et al., 2015). The diversity based on ITS sequences was lower thanC. dielsiana (ITS: H d=0.879, π=3.56) (Zhu et al. , 2019), which was ought to be a result of less sampling, might not really mean a lower diversity level. The broad spreading pattern, allowed by its high adaptation ability, must be a significant reason for the high diversity, since diverse topographies such as alps, mountains and hills, as well as plains, additionally along with different climate zones have provided variant habitats for C. serrulata during adaptation in diffusion which impelled variations and high diversity. Obviously, large sampling, covering the most of its natural distribution records, was also a fundamental factor. Besides, another reason may be the long evolutionary history of C. serrulata , which was dated back to 10.60 Mya, even earlier than C. dielsiana (6.28 Mya) (Zhu et al., 2019), because the long existence allowed a more multiple accumulation of variants, especially strengthened by a wide and strong adaptation.