Hunan Botanical Garden
Outstanding Youth Training Project for Innovation on Forestry Science and Technology of Hunan Province, China (XLK202108-6)，Forestry Science and Technology Development Project of National Forestry and Grassland Administration, China (KJZXSA2019037)，Special Project for Forestry Science and Technology Innovation of Hunan Province, China (XLK201914)
华中樱是原产于我国的野生樱花，湖南省是其主要分布区域，开展湖南省华中樱遗传多样性研究，为种质资源保护及开发利用奠定基础。通过对ITS序列进行PCR扩增和测序，应用遗传学软件分析湖南省10个华中樱群体207个个体的遗传多样性和遗传结构。结果表明，湖南省华中樱遗传多样性较高(Pi=0.0056，Hd=0.792)，207份种质资源可分为14个单倍型，其中来自怀化市中方县的群体ZF遗传多样性最高(Pi=0.00436，Hd=0.763)，其次是来自衡阳市南岳区的群体NY (Pi=0.00366，h=4，Hd=0.784)，来自郴州市苏仙区的群体SX的遗传多样性最低(Pi=0.00028，h=2，Hd=0.199)。AMOVA分析结果表明，60%的遗传变异存在于华中樱群体间，40%存在于群体内，大部分群体之间存在较大的遗传分化，其中来自常德市石门县的群体SM和来自郴州市苏仙区的群体SX之间的遗传分化指数(Fst)高达0.96571。中性检验结果表明，Tajima’s D(1.02121)和Fu and Li’s D(1.07527)均为正值，但统计检验不显著(P>0.10)；错配分布分析结果显示，错配分布呈双峰曲线，表明湖南省华中樱群体遵循中性进化模式，且进化过程中可能经历了平衡选择或突然群体收缩。Mantel test检验表明，群体之间的地理距离与遗传距离存在显著的正相关性(r=0.3356，P=0.026<0.05)。湖南省华中樱种质资源遗传多样性水平较高，群体间遗传分化明显且符合距离隔离模型。
To study the genetic diversity of Cerasus conradinae so as to contribute to the conservation and utilization of its germplasm, the ITS sequence was amplified by PCR and then sequenced by Sanger method, and genetic analysis software was used to analyze the genetic diversity and genetic structure of 207 individuals from 10 populations of C. conradinae in Hunan Province. The genetic diversity of C. conradinae in Hunan Province was relatively high (Pi=0.0056, Hd=0.792), and the 207 germplasms can be divided into 14 haplotypes. Among them, the population ZF from Zhongfang County, Huaihua City has the highest genetic diversity (Pi=0.00436, Hd=0.763), followed by the population NY from Nanyue District of Hengyang City (Pi=0.00366, Hd=0.784), and the population SX from Suxian District of Chenzhou City had the lowest genetic diversity (Pi=0.00028, Hd=0.199). The results of AMOVA analysis showed that 60% of the genetic variation existed among the populations of C. conradinae, 40% existed within the populations, and there was a large genetic differentiation among most of the populations. Among them, the genetic differentiation index (Fst) between populations SX and SM was as high as 0.96571. The neutral test results showed that the values of Tajima''s D (1.02121) and Fu and Li''s D (1.07527) are both positive, but statistical tests were not significant (P>0.10); the results of the mismatch distribution analysis showed that the mismatch distribution presented a bimodal curve. This indicated that the population of C. conradinae in Hunan Province followed a neutral evolutionary model, and might have experienced balanced selection or sudden population shrinkage during the evolution process. Mantel test showed that there was a positive correlation between geographic distance and genetic distance among the populations (r=0.3356, P=0.026<0.05). The genetic diversity of C. conradinae germplasms in Hunan Province was relatively high, and the genetic differentiations among populations were obvious and conformed to the Isolation-by-distance (IBD) model.