Laface Valentina Lucia Astrid, Cavallini Marta, Di Iorio Antonino, Lombardo Gianluca, Binelli Giorgio, Sorgonà Agostino, Musarella Carmelo Maria, Spampinato Giovanni
Department of AGRARIA, University "Mediterranea" of Reggio Calabria, Feo di Vito, 89124, Reggio Calabria, Italy.
Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy.
Heliyon. 2024 Aug 8;10(16):e35875. doi: 10.1016/j.heliyon.2024.e35875. eCollection 2024 Aug 30.
Assessing the degree of genetic diversity and differentiation of rare or endangered endemic species is essential to evaluate the conservation status of populations and successively implement appropriate conservation strategies. We investigated the population structure of Ard., a scapose hemicryptophyte endemic to Calabria (southern Italy), both to answer questions about its genetic structure and to determine whether the actual population size has undergone significant demographic changes in the near past. The data obtained from the census showed that the populations are characterised by a greater number of adult individuals than juveniles and are on declining. The genetic analysis carried out on 99 individuals from four populations of the species under study, shows a mean expected heterozygosity value of 0.50 and an overall differentiation value of 0.083. The population structure shows that the four studied populations are distinct genetic units, genetically linked to four different ancestral gene pools. Bayesian analysis based on ABC models indicates that the present populations underwent a significant reduction in size in the past. This corresponds to the demographic decline at the end of the 19th century, which according to the literature, was due to the strong anthropic pressure (agriculture, grazing, fire and plantations) of Reggio Calabria suburbs. We can therefore conclude that populations are not affected by inbreeding and low genetic diversity and that there is no immediate danger of genetic erosion, and that the problems associated with population decline, past and present, are exclusively due to anthropogenic causes.
评估珍稀或濒危特有物种的遗传多样性程度和分化情况对于评估种群的保护状况并进而实施适当的保护策略至关重要。我们调查了Ard.的种群结构，Ard.是一种生长于意大利南部卡拉布里亚地区的具花葶的地面芽植物，旨在回答有关其遗传结构的问题，并确定实际种群数量在近期是否经历了显著的人口统计学变化。从普查中获得的数据显示，该种群的成年个体数量多于幼年个体，且种群数量正在下降。对来自该研究物种四个种群的99个个体进行的遗传分析表明，平均期望杂合度值为0.50，总体分化值为0.083。种群结构表明，所研究的四个种群是不同的遗传单位，在遗传上与四个不同的祖先基因库相连。基于近似贝叶斯计算（ABC）模型的贝叶斯分析表明，当前种群在过去经历了显著的数量减少。这与19世纪末的人口统计学下降相对应，根据文献记载，这是由于雷焦卡拉布里亚郊区强大的人为压力（农业、放牧、火灾和种植园）造成的。因此，我们可以得出结论，种群不受近亲繁殖和低遗传多样性的影响，不存在遗传侵蚀的直接危险，并且与种群数量下降相关的过去和现在的问题完全是由人为原因造成的。
