Aguirre-Morales Carolina Adriana, Thomas Evert, Cardozo Carlos Ivan, Gutiérrez Janeth, Alcázar Caicedo Carolina, Moscoso Higuita Luis Gonzalo, Becerra López-Lavalle Luis Augusto, González Mailyn Adriana
Universidad Nacional de Colombia Sede Palmira Palmira Colombia.
Bioversity International Lima Peru.
Ecol Evol. 2020 Feb 5;10(4):1905-1916. doi: 10.1002/ece3.6005. eCollection 2020 Feb.
is a multipurpose tree species of seasonally dry tropical forests (SDTFs) of Mesoamerica and northern South America typically cultivated in silvopastoral and other agroforestry systems around the world, a trend that is bound to increase in light of multimillion hectare commitments for forest and landscape restoration. The effective conservation and sustainable use of requires detailed knowledge of its genetic diversity across its native distribution range of which surprisingly little is known to date. We assessed the genetic diversity and structure of across twelve representative locations of SDTF in Colombia, and how they may have been shaped by past climatic changes and human influence. We found four different genetic groups which may be the result of differentiation due to isolation of populations in preglacial times. The current distribution and mixture of genetic groups across STDF fragments we observed might be the result of range expansion of SDTFs during the last glacial period followed by range contraction during the Holocene and human-influenced movement of germplasm associated with cattle ranching. Despite the fragmented state of the presumed natural stands we sampled, we did not find any signs of inbreeding, suggesting that gene flow is not jeopardized in humanized landscapes. However, further research is needed to assess potential deleterious effects of fragmentation on progeny. Climate change is not expected to seriously threaten the in situ persistence of populations and might present opportunities for future range expansion. However, the sourcing of germplasm for tree planting activities needs to be aligned with the genetic affinity of reference populations across the distribution of Colombian SDTFs. We identify priority source populations for i conservation based on their high genetic diversity, lack or limited signs of admixture, and/or genetic uniqueness.
是中美洲和南美洲北部季节性干燥热带森林(SDTFs)中的一种多用途树种,通常在世界各地的农牧林业和其他农林业系统中种植,鉴于数百万公顷的森林和景观恢复承诺,这种趋势必然会增加。对其进行有效的保护和可持续利用需要详细了解其在原生分布范围内的遗传多样性,然而令人惊讶的是,迄今为止人们对此知之甚少。我们评估了哥伦比亚SDTF十二个代表性地点的该树种的遗传多样性和结构,以及它们可能如何受到过去气候变化和人类影响的塑造。我们发现了四个不同的遗传群体,这可能是由于冰川期前种群隔离导致分化的结果。我们观察到的当前遗传群体在SDTF片段中的分布和混合情况,可能是上一个冰川期SDTFs范围扩张,随后在全新世期间范围收缩以及与养牛业相关的种质受人类影响迁移的结果。尽管我们采样的假定天然林分处于碎片化状态,但我们没有发现任何近亲繁殖的迹象,这表明在人为化景观中基因流动没有受到威胁。然而,需要进一步研究来评估碎片化对后代的潜在有害影响。预计气候变化不会严重威胁该树种种群的原地持久性,并且可能为未来范围扩张带来机会。然而,植树活动的种质来源需要与哥伦比亚SDTF分布范围内参考种群的遗传亲和力保持一致。我们根据其高遗传多样性、缺乏或有限的混合迹象和/或遗传独特性,确定了该树种保护的优先来源种群。