Fogelström Elsa, Zacchello Giulia, Ehrlén Johan
Department of Ecology, Environment and Plant Science Stockholm University Stockholm Sweden.
Bolin Centre for Climate Research Stockholm University Stockholm Sweden.
Ecol Evol. 2022 Feb 15;12(2):e8610. doi: 10.1002/ece3.8610. eCollection 2022 Feb.
The timing of different life-history events is often correlated, and selection might only rarely be exerted independently on the timing of a single event. In plants, phenotypic selection has often been shown to favor earlier flowering. However, little is known about to what extent this selection acts directly versus indirectly via vegetative phenology, and if selection on the two traits is correlational. We estimated direct, indirect, and correlational phenotypic selection on vegetative and reproductive phenology over 3 years for flowering individuals of the perennial herb . Direct selection favored earlier flowering and shorter timespans between leaf-out and flowering in all years. However, early flowering was associated with early leaf-out, and the direction of selection on leaf-out day varied among years. As a result, selection on leaf-out weakened selection for early flowering in one of the study years. We found no evidence of correlational selection. Our results highlight the importance of including temporally correlated traits when exploring selection on the phenology of seasonal events.
不同生活史事件的时间安排往往相互关联，而且自然选择很少会独立作用于单个事件的时间安排。在植物中，表型选择常常表现为有利于更早开花。然而，对于这种选择在多大程度上直接作用于开花，以及在多大程度上通过营养物候间接作用，以及这两个性状的选择是否相关，我们知之甚少。我们对一种多年生草本植物的开花个体，在3年时间里对营养物候和生殖物候进行了直接、间接和相关表型选择的估计。直接选择在所有年份都有利于更早开花以及出叶到开花之间更短的时间跨度。然而，早开花与早出叶相关，而且出叶日期的选择方向在不同年份有所不同。结果，在其中一个研究年份里，对出叶的选择削弱了对早开花的选择。我们没有发现相关选择的证据。我们的结果突出了在探索对季节性事件物候的选择时纳入时间上相关性状的重要性。
