Pollen dispersal and genetic variation in an early-successional forest herb in a peri-urban forest.
Pollen dispersal and genetic variation in an early-successional forest herb in a peri-urban forest.
复制标题
城郊森林中早期演替森林草本植物的花粉传播和遗传变异。
DOI：
10.1111/j.1438-8677.2008.00176.x
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发表时间：
2009
期刊：
影响因子：
3.9
通讯作者：
F. Van Rossum
中科院分区：
文献类型：
--
作者：
F. Van Rossum
为了保护森林植物物种的特别高的限制下，代表城市环境，有必要确定人口的持久性的关键因素。本研究探讨内和种群间的花粉传播，使用荧光染料作为花粉类似物，遗传变异和结构，使用15个等位酶位点的矢车菊，昆虫授粉，早期演替森林两年生草本植物发生在城市边缘的森林（布鲁塞尔市区，比利时）。染料扩散呈指数衰减分布，大多数染料转移发生在短距离（<15米），只有少数长距离事件（高达743米）。C的花朵主要由食蚜蝇（双翅目）和小蜜蜂访问，它们通常被认为是短距离的花粉传播者，偶尔也有大黄蜂，它们通常是长距离的花粉传播者。小型和大型染料源种群的染料沉积模式不同。种群表现出低的遗传多样性，高的近交系数（F（IS））和高的遗传分化（F（ST）），这表明有限的基因流，这可以预期的早期演替两年期的物种与占主导地位的自交育种系统和波动的人口规模。招募率和等位基因丰富度和预期杂合性之间的正相关关系，并没有显着的遗传变异和人口规模之间的相关性，建议从种子库的幼苗招募，有助于保持遗传多样性。长距离的染料扩散事件表明传粉者运动沿着城市森林路径和道路边缘。因此，这些景观要素可能具有潜在的保护价值，有助于连接早期演替物种种群位于斑块开放的栖息地。
In order to conserve forest plant species under the particularly high constraints that represent urban surroundings, it is necessary to identify the key factors for population persistence. This study examined within- and between-population pollen dispersal using fluorescent dye as pollen analogue, and genetic variation and structure using 15 allozyme loci in Centaurium erythraea, an insect-pollinated, early-successional forest biennial herb occurring in a peri-urban forest (Brussels urban zone, Belgium). Dye dispersal showed an exponential decay distribution, with most dye transfers occurring at short distances (<15 m), and only a few long-distance events (up to 743 m). Flowers of C. erythraea are mainly visited by Syrphids (Diptera) and small bees, which are usually considered as short-distance pollen dispersers, and occasionally by bumblebees, which are usually longer-distance pollen dispersers. Small and large dye source populations differed in dye deposition patterns. The populations showed low genetic diversity, high inbreeding coefficients (F(IS)) and high genetic differentiation (F(ST)), suggesting restricted gene flow, which can be expected for an early-successional biennial species with a predominantly selfing breeding system and fluctuating population sizes. The positive relationship between recruitment rate and allelic richness and expected heterozygosity, and the absence of significant correlations between genetic variation and population size suggest seedling recruitment from the seed bank, contributing to maintain genetic diversity. Long-distance dye dispersal events indicate pollinator movements along urban forest path and road verges. These landscape elements might therefore have a potential conservation value by contributing to connectivity of early-successional species populations located in patchy open habitats.