Serrote C M L, Reiniger L R S, Stefenon V M, Curti A R, Costa L S, Paim A F
Departamento de Silvicultura e Manejo Florestal, Faculdade de Ciências Agrárias, Universidade Lúrio, Campus Universitário, Unango, Mozambique.
Núcleo de Biotecnologia e Melhoramento, Universidade Federal de Santa Maria, Campus Sede, Santa Maria, RS, Brasil
Genet Mol Res. 2016 Aug 29;15(3):gmr8410. doi: 10.4238/gmr.15038410.
Computer simulations are an important tool for developing conservation strategies for forest species. This study used simulations to investigate the genetic, ecological, and reproductive patterns that contribute to the genetic structure of the tree Luehea divaricata Mart. & Zucc. in five forest fragments in the Brazilian Pampa biome. Using the EASYPOP model, we determined the selfing and migration rates that would match the corresponding genetic structure of microsatellite marker data (based on observed and expected heterozygosity parameters). The simulated reproductive mode was mixed, with a high rate of outcrossing (rate = 0.7). This was consistent with a selfing-incompatible system in this species, which reduced, but did not prevent, selfing. The simulated migration rate was 0.02, which implied that the forest fragments were isolated by distance, and that the inbreeding coefficients were high. Based on Nei's gene diversity analysis, 94% of the genetic variability was distributed within the forest fragments, and only 6% of the genetic diversity was caused by differences between them. Furthermore, the minimum viable population and minimum viable area genetic conservation parameters (which determine conservation potential in the short and long term) suggested that only the Inhatinhum forest fragment had the short-term potential to maintain its genetic diversity. However, in the long term, none of the forest fragments proved to be sustainable, indicating that the populations will require intervention to prevent a decline in genetic variability. The creation of ecological corridors could be a useful solution to connect forest fragments and enhance gene flow between them.
计算机模拟是制定森林物种保护策略的重要工具。本研究利用模拟来调查影响巴西潘帕生物群落五个森林片段中树木线裂南美椴（Luehea divaricata Mart. & Zucc.）遗传结构的遗传、生态和繁殖模式。使用EASYPOP模型，我们确定了与微卫星标记数据的相应遗传结构相匹配的自交率和迁移率（基于观察到的和预期的杂合度参数）。模拟的繁殖模式是混合的，异交率很高（率 = 0.7）。这与该物种的自交不亲和系统一致，该系统减少了但并未阻止自交。模拟的迁移率为0.02，这意味着森林片段因距离而隔离，且近亲繁殖系数很高。基于内氏基因多样性分析，94%的遗传变异分布在森林片段内，只有6%的遗传多样性是由它们之间的差异引起的。此外，最小可存活种群和最小可存活面积遗传保护参数（决定短期和长期的保护潜力）表明，只有因哈廷胡姆森林片段具有在短期内维持其遗传多样性的潜力。然而，从长期来看，没有一个森林片段被证明是可持续的，这表明这些种群需要干预以防止遗传变异性下降。建立生态走廊可能是连接森林片段并增强它们之间基因流动的有效解决方案。
