Common ragweed, Ambrosia artemisiifolia L. (Asteraceae), an annual weed native to Northern America, has become invasive in numerous countries in Europe. South-central and south-eastern European regions are the most affected. In the western and northern parts of Europe and mountain ranges ragweed does not behave as an invasive weed, yet. Climate change is expected to facilitate the establishment of ragweed as a self-propagating weed in these regions in the near future. The major concern regarding common ragweed is due to its highly allergenic pollen that causes sensitisation of the population, generating huge medical costs. Ragweed also has increasingly become a major weed in European agriculture, especially in spring-sown crops such as sunflower, maize, sugar beet and soya beans. Because of the taxonomic relatedness with sunflower, herbicides are of limited use in this crop, facilitating the spread of Ambrosia throughout Europe in birdseed, other feeding mixtures and crop seed. Herbicides and mechanical control (uprooting, cutting, ploughing) are best suited as local and short-term measures to eradicate initial and small populations, and to mitigate further spread of established populations. In other crops herbicide treatments may be sufficient to prevent yield losses, but often this in not sufficient to prevent ragweed populations from flowering and setting seeds. In non-agricultural land, management of ragweed using herbicides is too expensive and, furthermore, the need to protect the accompanying vegetation does not allow large-scale application of herbicides. Thus, the ragweed population is increasing. Bioactive fungal metabolites have been long considered for their potential direct use as natural herbicides, as a lead for new herbicides or to discover novel mechanisms of action. The authors of this article have a long history and a strong expertise in the production and chemical and biological characterization of novel bioactive metabolites from microorganisms and plants. However, despite the enormous number of novel metabolites identified and available in their labs, none of them has ever been tested against A. artemisiifolia. Thus, a number of selected metabolites produced and purified by the culture of pathogenic fungi and plants was used in preliminary tests to evaluate their effects on the germination of ragweed seeds, the elongation of seedling rootlets and on the development of necrotic spots on leaves. The present communication reports the first results of these biological assays, discussing the potential use of the most interesting metabolites as natural herbicides for ragweed management.
Effects of fungal toxins on Ambrosia artemisiifolia
Vurro M;Evidente A
2015
Abstract
Common ragweed, Ambrosia artemisiifolia L. (Asteraceae), an annual weed native to Northern America, has become invasive in numerous countries in Europe. South-central and south-eastern European regions are the most affected. In the western and northern parts of Europe and mountain ranges ragweed does not behave as an invasive weed, yet. Climate change is expected to facilitate the establishment of ragweed as a self-propagating weed in these regions in the near future. The major concern regarding common ragweed is due to its highly allergenic pollen that causes sensitisation of the population, generating huge medical costs. Ragweed also has increasingly become a major weed in European agriculture, especially in spring-sown crops such as sunflower, maize, sugar beet and soya beans. Because of the taxonomic relatedness with sunflower, herbicides are of limited use in this crop, facilitating the spread of Ambrosia throughout Europe in birdseed, other feeding mixtures and crop seed. Herbicides and mechanical control (uprooting, cutting, ploughing) are best suited as local and short-term measures to eradicate initial and small populations, and to mitigate further spread of established populations. In other crops herbicide treatments may be sufficient to prevent yield losses, but often this in not sufficient to prevent ragweed populations from flowering and setting seeds. In non-agricultural land, management of ragweed using herbicides is too expensive and, furthermore, the need to protect the accompanying vegetation does not allow large-scale application of herbicides. Thus, the ragweed population is increasing. Bioactive fungal metabolites have been long considered for their potential direct use as natural herbicides, as a lead for new herbicides or to discover novel mechanisms of action. The authors of this article have a long history and a strong expertise in the production and chemical and biological characterization of novel bioactive metabolites from microorganisms and plants. However, despite the enormous number of novel metabolites identified and available in their labs, none of them has ever been tested against A. artemisiifolia. Thus, a number of selected metabolites produced and purified by the culture of pathogenic fungi and plants was used in preliminary tests to evaluate their effects on the germination of ragweed seeds, the elongation of seedling rootlets and on the development of necrotic spots on leaves. The present communication reports the first results of these biological assays, discussing the potential use of the most interesting metabolites as natural herbicides for ragweed management.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
