Abstract:
In this work, we analyzed the morphology and genetic structure of Teucrium montanum, T. capitatum and their hybrid T. × rohlenae from three syntopic populations. A morphometric study showed that the parents and their hybrids exhibited continuous morphological variation, with the hybrid positioned exactly between the parents. Genetic analysis revealed that plants morphologically identified as T. × rohlenae are fertile hybrids that produce hybrid swarms dominated by later-generation hybrids. This suggests that introgression, rather than speciation, is the more likely outcome of hybridization between these plant species. The extent and direction of gene flow between the two species differed markedly between the three syntopic localities. At the Trilj locality, it was clearly unidirectional, with T. capitatum playing the dominant role. At the Sićevo locality, gene flow was slightly asymmetric, favoring the genetic background of T. capitatum, while at the Sliven site, it was completely asymmetric in the opposite direction. The extreme case of unidirectional gene flow was observed at the Trilj locality where plants morphologically identified as T. montanum could not be genetically distinguished from T. capitatum. This suggests that interspecific hybridization occurred long ago, leading to introgression and cryptic hybrids, blurring of species boundaries and generating evolutionary noise.
摘要:
在这项工作中,我们分析了小麦的形态和遗传结构,T.capitatum及其杂种T.×rohlenae来自三个同位种群。形态计量学研究表明,亲本及其杂种表现出连续的形态变异,杂种恰好位于父母之间。遗传分析显示,在形态上鉴定为T.×rohlenae的植物是可育的杂种,产生以后代杂种为主的杂种群。这表明渗入,而不是物种形成,是这些植物物种之间杂交的更可能的结果。两个物种之间的基因流的程度和方向在三个同位位置之间显着不同。在Trilj地区,这显然是单向的,以T.Capetatum发挥主导作用。在西奇沃地区,基因流稍微不对称,有利于头花T.的遗传背景,而在Sliven现场,它在相反的方向上是完全不对称的。在Trilj地区观察到了单向基因流动的极端情况,在该地区,在形态上鉴定为T.montanum的植物无法在遗传上与T.capetatum区分开。这表明种间杂交发生在很久以前,导致渗入和神秘杂交,物种边界模糊并产生进化噪声。