Mating systems of diploid and allotetraploid populations of Tragopogon (Asteraceae).: II.: Artificial populations
Mating systems of diploid and allotetraploid populations of Tragopogon (Asteraceae).: II.: Artificial populations
复制标题
DOI：
10.1046/j.1365-2540.2000.00654.x
复制
发表时间：
2000-04-01
期刊：
影响因子：
3.8
通讯作者：
Soltis, PS
中科院分区：
文献类型：
--
作者：
Cook, LM;Soltis, PS
多倍体化一直被认为是植物多样化的重要力量。理论模型预测，多倍体可能会表现出更高的自花受精率比密切相关的二倍体物种。新多倍体的Tragopogon mirus（4 n）野生群体的异交率略高于其祖先之一Tragopogon mirus（4 n）的群体。P.t.（2n）.在本研究中，T.和T.使用构建的人工阵列来估计mirus，以最大化检测异交事件的机会。人工二倍体群体比四倍体群体（t =0.591;家系水平估计值范围从0.00到1.14）具有更高的异交（t =0.727;家系水平估计值范围从0.00到1.32），尽管它们之间的差异在统计学上不显著。这项研究的结果，结合那些以前的野生种群的工作，表明这些物种的交配系统在种群之间的差异比倍性水平。这可能是因为四倍体物种的起源相对较近;自四倍体形成以来，交配系统发生转变的时间可能不够。
Polyploidization has long been recognized as an important force in the diversification of plants. Theoretical models predict that polyploids may be expected to exhibit higher rates of self-fertilization than do closely related diploid species. Wild populations of the neopolyploid Tragopogon mirus (4n) exhibited slightly higher rates of outcrossing than did populations of one of its progenitors, T. dubius (2n). In the current study, outcrossing rates in populations of T. dubius and T. mirus were estimated using artificial arrays constructed to maximize the chances of detecting outcrossing events. The artificial diploid population is more highly outcrossing (t=0.727; family-level estimates range from 0.00 to 1.32) than the tetraploid population (t=0.591; family-level estimates range from 0.00 to 1.14), although the difference between them is not statistically significant. The results of this study, combined with those of the previous work on wild populations, suggest that mating systems in these species vary more among populations than between ploidal levels. This could be because of the relatively recent origins of the tetraploid species; there may have been insufficient time since the formations of the tetraploids for shifts in mating systems to occur.