BACKGROUND AND AIMS: Allelopathy may drive invasions of some exotic plants, although empirical evidence for this theory remains largely inconclusive. This could be related to the large intraspecific variability of chemically mediated plant-plant interactions, which is poorly studied. This study addressed intraspecific variability in allelopathy of Heracleum mantegazzianum (giant hogweed), an invasive species with a considerable negative impact on native communities and ecosystems. METHODS: Bioassays were carried out to test the alleopathic effects of H. mantegazzianum root exudates on germination of Arabidopsis thaliana and Plantago lanceolata. Populations of H. mantegazzianum from the Czech Republic were sampled and variation in the phytotoxic effects of the exudates was partitioned between areas, populations within areas, and maternal lines. The composition of the root exudates was determined by metabolic profiling using ultra-high-performance liquid chromatography with time-of-flight mass spectrometry, and the relationships between the metabolic profiles and the effects observed in the bioassays were tested using orthogonal partial least-squares analysis. KEY RESULTS: Variance partitioning indicated that the highest variance in phytotoxic effects was within populations. The inhibition of germination observed in the bioassay for the co-occurring native species P. lanceolata could be predicted by the metabolic profiles of the root exudates of particular maternal lines. Fifteen compounds associated with this inhibition were tentatively identified. CONCLUSIONS: The results present strong evidence that intraspecific variability needs to be considered in research on allelopathy, and suggest that metabolic profiling provides an efficient tool for studying chemically mediated plant-plant interactions whenever unknown metabolites are involved.
- MeSH
- Allelopathy * MeSH
- Arabidopsis drug effects MeSH
- Heracleum chemistry genetics metabolism MeSH
- Species Specificity MeSH
- Ecosystem MeSH
- Germination drug effects MeSH
- Plant Roots chemistry genetics metabolism MeSH
- Metabolome * MeSH
- Plantago drug effects MeSH
- Plant Exudates chemistry isolation & purification metabolism MeSH
- Introduced Species MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
elektronický časopis
- Conspectus
- Biologické vědy
- NML Fields
- farmacie a farmakologie
- NML Publication type
- elektronické časopisy
The terms 'brûlé' and 'burnt' are used to describe vegetation-devoid areas of the ground around a range of woody plants interacting with certain truffle species. Increasing interest is currently focused on a systematic search for and study of volatile organic compounds (VOCs) emitted by truffles in the course of their life cycle. These metabolites are now recognized as biochemicals with an important impact on burnt formation. Based on current molecular approaches, Tuber melanosporum is emerging as an aggressive colonizer of the brûlé, dominant in competition with indigenous brûlé-associated organisms, suppressing their richness and biodiversity. There is compelling evidence that mycelia, mycorrhizae, and fruiting bodies of brûlé-forming truffles have evolved diffusible metabolites for their survival, typically characterized as having harmful effects on weeds, impairing seed germination, altering root morphogenesis and plant hormonal balance, or inhibiting the native rhizospheric microflora regularly associated with the brûlé. These effects can be widely interpreted as allelopathic phenomena, and the brûlé may thus be regarded as a promising opportunity to study truffle allelopathy. Considering the outstanding success of the genome analysis in T. melanosporum, we are facing a very difficult task to proceed from the molecular to the ecological level.
- MeSH
- Ascomycota genetics physiology MeSH
- Biodiversity MeSH
- Biological Products chemistry metabolism MeSH
- Ecology MeSH
- Mycorrhizae genetics physiology MeSH
- Soil Microbiology MeSH
- Volatile Organic Compounds chemistry metabolism MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Review MeSH
The invasion success of introduced plants is frequently explained as a result of competitive interactions with native flora. Although previous theory and experiments have shown that plants are largely equivalent in their competitive effects on each other, competitive nonequivalence is hypothesized to occur in interactions between native and invasive species. Small overlap in resource use with unrelated native species, improved competitiveness, and production of novel allelochemicals are all believed to contribute to the invasiveness of introduced species. I tested all three assumptions in a common-garden experiment by examining the effect of plant origin and relatedness on competition intensity. Competitive interactions were explored within 12 triplets, each consisting of an invasive species, a native congeneric (or confamilial) species, and a native heterogeneric species that are likely to interact in the field. Plants were grown in pots alone or in pairs and in the absence or the presence of activated carbon to control for allelopathy. I found that competition intensity was not influenced by the relatedness or origin of competing neighbors. Although some exotic species may benefit from size advantages and species-specific effects in competitive interactions, none of the three mechanisms investigated is likely to be a principal driver of their invasiveness.
- MeSH
- Pheromones MeSH
- Phylogeny MeSH
- Phylogeography MeSH
- Magnoliopsida MeSH
- Introduced Species MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
