斯特瓦蒂亚·奥瓦塔(cav。)Weatherby,通常被称为Stewartia山,是原产于美国东南部(U.S.)的林下树。这种相对罕见的物种出现在弗吉尼亚州的孤立种群中,肯塔基,田纳西州,北卡罗来纳州,南卡罗来纳州,格鲁吉亚,阿拉巴马,还有密西西比州.作为一个物种,S、Ovata在很大程度上被忽视了,关于其生态的信息有限,这给保护工作带来了障碍。Stewartiaovata生机勃勃,夏天盛开的白色大花,有各种各样的花丝颜色,提示观赏产业重视的潜在园艺性状。然而,美国卵黄生长相对缓慢,由于种子休眠时间长,传播是具有挑战性的有限的成功率。这就需要评估卵黄链球菌种群中目前的遗传多样性,以告知该物种的潜在保护和恢复。这里,我们采用基因分型-测序(GBS)方法来描述美国东部阿巴拉契亚南部地区卵黄链球菌的空间分布和遗传多样性.在来自11个收集位点的147个个体中鉴定出总共4475个单核苷酸多态性(SNP)。我们的结果表明遗传多样性低(He=0.216),种群结构的存在(K=2),有限分化(FST=0.039),和我们的亚群之间的高基因流量(Nm=6.16)。主成分分析证实了结构的发现,确认存在两个不同的S.ovata亚群。一个亚群主要包含来自坎伯兰高原的基因型,田纳西州,而另一种是田纳西州大烟山脉中存在的基因型,北卡罗来纳州,和南塔哈拉的部分,佐治亚州的Chattahoochee-Oconee国家森林,强调海拔可能在其分布中起着重要作用。我们的结果进一步表明近交系数低(FIS=0.070),预计会出现异类树种。这项研究进一步提供了对现存亚群的必要见解,并为S.ovata的保护工作提供了宝贵的资源。
Stewartia ovata (cav.) Weatherby, commonly known as mountain stewartia, is an understory tree native to the southeastern United States (U.S.). This relatively rare species occurs in isolated populations in Virginia, Kentucky, Tennessee, North Carolina, South Carolina, Georgia, Alabama, and Mississippi. As a species, S. ovata has largely been overlooked, and limited information is available regarding its ecology, which presents obstacles to
conservation efforts. Stewartia ovata has vibrant, large white flowers that bloom in summer with a variety of filament colors, suggesting potential horticultural traits prized by ornamental industry. However, S. ovata is relatively slow growing and, due to long seed dormancy, propagation is challenging with limited success rates. This has created a need to assess the present genetic diversity in S. ovata populations to inform potential
conservation and restoration of the species. Here, we employ a genotyping-by-sequencing (GBS) approach to characterize the spatial distribution and genetic diversity of S. ovata in the southern Appalachia region of the eastern United States. A total of 4475 single nucleotide polymorphisms (SNPs) were identified across 147 individuals from 11 collection sites. Our results indicate low genetic diversity (He = 0.216), the presence of population structure (K = 2), limited differentiation (F ST = 0.039), and high gene flow (Nm = 6.16) between our subpopulations. Principal component analysis corroborated the findings of STRUCTURE, confirming the presence of two distinct S. ovata subpopulations. One subpopulation mainly contains genotypes from the Cumberland Plateau, Tennessee, while the other consists of genotypes present in the Great Smoky Mountain ranges in Tennessee, North Carolina, and portions of Nantahala, Chattahoochee-Oconee national forests in Georgia, highlighting that elevation likely plays a major role in its distribution. Our results further suggested low inbreeding coefficient (F IS = 0.070), which is expected with an outcrossing tree species. This research further provides necessary insight into extant subpopulations and has generated valuable resources needed for
conservation efforts of S. ovata.