Genetic and ecological drivers of successful bioinvasion by Gracilaria vermiculophylla

• Applicant: Professor Martin Wahl, Ph.D.
• Subject Area: Ecology and Biodiversity of Plants and Ecosystems
• Term: from 2017 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 338827057

The Asia-endemic red alga Gracilaria vermiculophylla invaded the Atlantic and Eastern Pacific coasts since the 1980s and has imposed drastic impacts on community structure and ecosystem function. Although eco-physiological and chemical studies revealed that some ecological traits and chemical defense to predators made considerable contribution to its rapid global invasion, no studies were conducted to reveal whether genetic and/or epigenetic variations and the rate of acclimation/adaptation to new environmental conditions account for the large-scale invasion success of G. vermiculophylla. We propose to elucidate the eco-genetic mechanisms behind the invasion of G. vermiculophylla. The aims of the Chinese side will include (1) the identification of genes with distinct expression profiles in native and invasive populations by transcriptomics and the analysis of how these genes contribute to the ecological adaptation to a wide range of novel environments, (2) the assessment of genetic diversity in and between native and invasive populations using AFLP genotyping, (3) the detection of epigenetic variation within the specific mitochondrial haplotype G. vermiculophylla (H6), which dominated the invasion of Atlantic and E Pacific coasts using MS-AFLP, and (4) the detection of genetic shifts at the population level that indicate selective survival of robust genotypes under stressful conditions during invasion. On the German side the aims will be (1) to determine whether native and invasive populations exhibit different tolerance widths towards environmental stress, (2) to assess the amount of intraspecific variance of stress sensitivity (the basis for adaptation) between native and invasive populations, (3) to compare the rate (i.e. speed) of acclimation/adaptation of native and invasive populations to new environmental conditions and (4) to investigate the role of associated microorganisms in the modulation of host responses to stress. The joint project will not only provide a comprehensive understanding of genetic and ecological mechanisms underlying successful seaweed invasion, but also help to develop a more effective monitoring management for candidate invasive seaweeds, which will mitigate and prevent seaweed invasions worldwide.

• DFG Programme: Research Grants
• International Connection: China
• Partner Organisation: Chinesisch-Deutsches Zentrum für Wissenschaftsförderung Beijing
• Cooperation Partner: Professorin Dr. Gaoge Wang