Fitness dynamics within a poplar hybrid zone: II. Impact of exotic sex on native poplars in an urban jungle

Ecology and Evolution

Amanda D. Roe²  Chris J.K. MacQuarrie¹  Marie-Claude Gros-Louis²  J. Dale Simpson³  Josyanne Lamarche¹  Tannis Beardmore³  Stacey L. Thompson²  Philippe Tanguay² 

[1] Natural Resources Canada, Canadian Forest Service, Sault Ste. Marie, Ontario, Canada;Natural Resources Canada, Canadian Forest Service, Québec, Québec, Canada;Natural Resources Canada, Canadian Forest Service, Fredericton, New-Brunswick, Canada

关键词: Anthropogenic disturbance;    disease susceptibility;    hybridization;    Populus;    postzygotic fitness;    SNP genotyping;    urban–forest interface;   

DOI  :  10.1002/ece3.1028

来源: Wiley

【 摘 要 】

Abstract

Trees bearing novel or exotic gene components are poised to contribute to the bioeconomy for a variety of purposes such as bioenergy production, phytoremediation, and carbon sequestration within the forestry sector, but sustainable release of trees with novel traits in large-scale plantations requires the quantification of risks posed to native tree populations. Over the last century, exotic hybrid poplars produced through artificial crosses were planted throughout eastern Canada as ornamentals or windbreaks and these exotics provide a proxy by which to examine the fitness of exotic poplar traits within the natural environment to assess risk of exotic gene escape, establishment, and spread into native gene pools. We assessed postzygotic fitness traits of native and exotic poplars within a naturally regenerated stand in eastern Canada (Quebec City, QC). Pure natives (P. balsamifera and P. deltoides spp. deltoides), native hybrids (P. deltoides × P. balsamifera), and exotic hybrids (trees bearing Populus nigra and P. maximowiczii genetic components) were screened for reproductive biomass, yield, seed germination, and fungal disease susceptibility. Exotic hybrids expressed fitness traits intermediate to pure species and were not significantly different from native hybrids. They formed fully viable seed and backcrossed predominantly with P. balsamifera. These data show that exotic hybrids were not unfit and were capable of establishing and competing within the native stand. Future research will seek to examine the impact of exotic gene regions on associated biotic communities to fully quantify the risk exotic poplars pose to native poplar forests.

【 授权许可】

CC BY   
© 2014 Natural Resources Canada. Ecology and Evolution published by John Wiley & Sons Ltd.

Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.