表型选择的组成部分：聚合花烟草的花粉输出与花冠宽度

COMPONENTS OF PHENOTYPIC SELECTION: POLLEN EXPORT AND FLOWER COROLLA WIDTH IN IPOMOPSIS AGGREGATA.

作者信息

Campbell Diane R, Waser Nickolas M, Price Mary V, Lynch Elizabeth A, Mitchell Randall J

机构信息

Department of Ecology and Evolutionary Biology, University of California, Irvine, CA, 92717, USA.

Rocky Mountain Biological Laboratory, Crested Butte, CO, 81224, USA.

出版信息

Evolution. 1991 Sep;45(6):1458-1467. doi: 10.1111/j.1558-5646.1991.tb02648.x.

DOI:10.1111/j.1558-5646.1991.tb02648.x

PMID:28563828

Abstract

In the hummingbird-pollinated herb Ipomopsis aggregata, selection through male function during pollination favors wide corolla tubes. We explored the mechanisms behind this selection, using phenotypic selection analysis to compare effects of corolla width on two components of male pollination success, pollinator visit rate and pollen exported per visit. During single visits by captive hummingbirds, flowers with wider corollas exported more pollen, and more dye used as a pollen analogue, to stigmas of recipient flowers. Corolla width was less strongly related to visit rate in the field, and had no direct effect on visit rate after nectar production and corolla length were controlled for. Moreover, the phenotypic selection differential was 80% higher for the effect on pollen exported per visit, suggesting that this is the more important mechanism of selection.

摘要

在由蜂鸟传粉的草本植物聚花Ipomopsis aggregata中，授粉过程中通过雄性功能进行的选择有利于宽花冠管。我们利用表型选择分析来比较花冠宽度对雄性授粉成功的两个组成部分（传粉者访花率和每次访花输出的花粉量）的影响，从而探究这种选择背后的机制。在圈养蜂鸟单次访花期间，花冠较宽的花朵向接受花的柱头输出了更多花粉，以及更多用作花粉类似物的染料。在野外，花冠宽度与访花率的相关性较弱，在控制花蜜产量和花冠长度后，花冠宽度对访花率没有直接影响。此外，每次访花输出花粉量的表型选择差异要高80%，这表明这是更重要的选择机制。