Wiehle Martin, Prinz Kathleen, Kehlenbeck Katja, Goenster Sven, Mohamed Seifeldin Ali, Finkeldey Reiner, Buerkert Andreas, Gebauer Jens
Organic Plant Production and Agroecosystems Research in the Tropics and Subtropics (OPATS), University of Kassel, Steinstraße 19, D-37213 Witzenhausen, Germany.
Institute of Systematic Botany with Herbarium Haussknecht and Botanical Garden, Friedrich-Schiller-University Jena, D-07743 Jena, Germany.
Am J Bot. 2014 Sep;101(9):1498-507. doi: 10.3732/ajb.1400198. Epub 2014 Sep 21.
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Adansonia digitata L. is one of the most important indigenous fruit trees of mainland Africa. Despite its significance for subsistence and income generation of local communities, little is known about the genetic and morphological variability of East African populations of A. digitata, including those of Sudan. The aim of the current study, therefore, was to analyze genetic and morphological variability of different baobab populations in Kordofan, Sudan and to estimate the effect of human intervention on genetic differentiation and diversity.•
A total of 306 trees were randomly sampled from seven spatially separated locations in the Nuba Mountains, Sudan, to cover a wide range of differing environmental gradients and management regimes ('homesteads' and 'wild'). Genetic analyses were conducted using nine microsatellite markers. Because of the tetraploid nature of A. digitata, different approaches were applied to estimate patterns of genetic diversity. Investigations were completed by measurements of dendrometric and fruit morphological characters.•
Genetic diversity was balanced and did not differ between locations or management regimes, although tendencies of higher diversity in 'homesteads' were observed. A Bayesian cluster approach detected two distinct gene pools in the sample set, mainly caused by one highly diverse population close to a main road. The variability of tree characters and fruit morphometries was high, and significantly different between locations.•
Results indicated a rather positive effect with human intervention. The observed populations provide a promising gene pool and likely comprise ecotypes well-adapted to environmental conditions at the northern distribution range of the species, which should be considered in conservation and management programs.
研究前提：猴面包树是非洲大陆最重要的本土果树之一。尽管它对当地社区的生计和创收具有重要意义，但对于包括苏丹在内的东非猴面包树种群的遗传和形态变异知之甚少。因此，本研究的目的是分析苏丹科尔多凡不同猴面包树种群的遗传和形态变异，并评估人为干预对遗传分化和多样性的影响。
方法：从苏丹努巴山脉七个空间上分离的地点随机抽取了306棵树，以涵盖广泛不同的环境梯度和管理方式（“家园”和“野生”）。使用九个微卫星标记进行遗传分析。由于猴面包树是四倍体，采用了不同方法来估计遗传多样性模式。通过测量树木测量学和果实形态特征完成调查。
主要结果：遗传多样性是平衡的，在不同地点或管理方式之间没有差异，尽管观察到“家园”中多样性有更高的趋势。贝叶斯聚类方法在样本集中检测到两个不同的基因库，主要是由靠近一条主要道路的一个高度多样的种群导致的。树木特征和果实形态测量的变异性很高，并且在不同地点之间存在显著差异。
结论：结果表明人为干预有相当积极的影响。观察到的种群提供了一个有前景的基因库，可能包含适应该物种北半分布范围环境条件的生态型，在保护和管理计划中应予以考虑。
