Hulme P.E., Bacher S., Kenis M., Klotz S., Kühn I., Minchin D., Nentwig W., Olenin S., Panov V., Pergl J., Pyšek P., Roques A., Sol D., Solarz W., Vilà M. (2008) Grasping at the routes of biological invasions: A framework for integrating pathways into policy. Journal of Applied Ecology. 45: 403-414.EnllaçDoi: 10.1111/j.1365-2664.2007.01442.x
1. Pathways describe the processes that result in the introduction of alien species from one location to another. A framework is proposed to facilitate the comparative analysis of invasion pathways by a wide range of taxa in both terrestrial and aquatic ecosystems. Comparisons with a range of data helped identify existing gaps in current knowledge of pathways and highlight the limitations of existing legislation to manage introductions of alien species. The scheme aims for universality but uses the European Union as a case study for the regulatory perspectives. 2. Alien species may arrive and enter a new region through three broad mechanisms: importation of a commodity, arrival of a transport vector, and/or natural spread from a neighbouring region where the species is itself alien. These three mechanisms result in six principal pathways: release, escape, contaminant, stowaway, corridor and unaided. 3. Alien species transported as commodities may be introduced as a deliberate release or as an escape from captivity. Many species are not intentionally transported but arrive as a contaminant of a commodity, for example pathogens and pests. Stowaways are directly associated with human transport but arrive independently of a specific commodity, for example organisms transported in ballast water, cargo and airfreight. The corridor pathway highlights the role transport infrastructures play in the introduction of alien species. The unaided pathway describes situations where natural spread results in alien species arriving into a new region from a donor region where it is also alien. 4. Vertebrate pathways tend to be characterized as deliberate releases, invertebrates as contaminants and plants as escapes. Pathogenic micro-organisms and fungi are generally introduced as contaminants of their hosts. The corridor and unaided pathways are often ignored in pathway assessments but warrant further detailed consideration. 5. Synthesis and applications. Intentional releases and escapes should be straightforward to monitor and regulate but, in practice, developing legislation has proved difficult. New introductions continue to occur through contaminant, stowaway, corridor and unaided pathways. These pathways represent special challenges for management and legislation. The present framework should enable these trends to be monitored more clearly and hopefully lead to the development of appropriate regulations or codes of practice to stem the number of future introductions. © 2007 The Authors.
Huntzinger C.I., James R.R., Bosch J., Kemp W.F. (2008) Laboratory bioassays to evaluate fungicides for chalkbrood control in larvae of the Alfalfa leafcutting bee (Hymenoptera: Megachilidae). Journal of Economic Entomology. 101: 660-667.EnllaçDoi: 10.1603/0022-0493(2008)101[660:LBTEFF]2.0.CO;2
Chalkbrood, a fungal disease in bees, is caused by several species of Ascosphaera. A. aggregata is a major mortality factor in populations of the alfalfa leafcutting bee, Megachile rotundata (F.) (Hymenoptera: Megachilidae) used in commercial alfalfa seed production. Four formulated fungicides, Benlate 50 WP, Captan, Orbit, and Rovral 50 WP were tested in the laboratory for efficacy against hyphal growth of A. aggregata cultures. The same fungicides, with the addition of Rovral 4 F, were tested for their effects on incidence of chalkbrood disease, and toxicity to M. rotundata larvae. Benlate, Rovral 50 WP, and Rovral 4 F reduced incidence of chalkbrood with minimal mortality on larval bees. Benlate and Rovral 50 WP also reduced hyphal growth. Orbit was effective in reducing hyphal growth, but it did not reduce incidence of chalkbrood and was toxic to bee larvae. Captan was not effective in reducing hyphal growth or chalkbrood incidence, and it was toxic to bee larvae. Fungicides that reduce incidence of chalkbrood and larval mortality in this laboratory study are candidates for further study for chalkbrood control.
Huntzinger C.I., James R.R., Bosch J., Kemp W.P. (2008) FunGicide tests on adult alfalfa leafcutting bees (Hymenoptera: Megachilidae). Journal of Economic Entomology. 101: 1088-1094.EnllaçDoi: 10.1603/0022-0493(2008)101[1088:FTOAAL]2.0.CO;2
Chalkbrood is a serious disease of alfalfa leafcutting bee Megachile rotundata (F.) (Hymenoptera: Megachilidae) larvae, causing upward of 20% infection in the field. The causative agent is the fungus Ascosphaera aggregata. This bee is used extensively for alfalfa seed pollination in the United States. Using laboratory bioassays, we previously demonstrated that fungicides can reduce chalkbrood levels in the larvae. Here, we evaluate the toxicity of four fungicides, Benlate, Captan, Orbit, and Rovral, to adult bees by using three different bioassays. In the first test, fungicides were applied to bees' thoraces. In the second test, mimicking foliage residue, a piece of filter paper soaked in fungicide was placed on the bottom of a container of bees. The third test evaluated oral toxicity by incorporating fungicides into a sugar-water solution that was fed to the bees. The filter paper test did not discriminate among the fungicides well, and the oral test resulted in the greatest mortality. Toxicity to males was greater than to females. The use of fungicides for chalkbrood control is a logical choice, but caution should be used in how they are applied in the presence of bees.
Terradas J, Peñuelas J (2008) Climate Change Policy: IPCC consensus is not enough. Ambio a Journal of the Human Environment 37: 321-322
Llusià J, Peñuelas J, Alessio GA, Estiarte M (2008) Contrasting species-specific, compound-specific, seasonal, and inter-annual responses of foliar isoprenoid emissions to experimental drought in a Mediterranean shrubland. International Journal of Plant Sciences. 169: 637–645.
Burriel JA, Ibáñez JJ, Masó J. (2008) SIOSE en Cataluña: obtención a partir del Mapa de Cubiertas del Suelo de Cataluña. Publicat a: Hernández L, Parreño J M (Eds.), Tecnologías de la Información. Servicio de Publicaciones y Difusión Científica de la ULPGC. Las Palmas de Gran Canaria. ISBN: 978-84-96971-53-0.
Ibàñez JJ, Burriel JA (2008) Mapa de cubiertas del suelo de Cataluña: Metodologia de la tercera edición. Tecnologías de la Información Geográfica para el Desarrollo Territorial. XIII Congreso Nacional de tecnologías de la información geográfica. Las Palmas de Gran Canaria. CD-ROM edition.
Huntzinger CI, James RR, Bosch J, Kemp WP (2008) Fungicide tests on adult Megachile rotundata (F.) (Hymenoptera: Megachilidae). Journal of Economic Entomology 101: 1088-1094.
Sardans J, Peñuelas J. Ogaya R (2008) Experimental drought reduced acid and alkaline phosphatase activity and increased organic extractable P in soil in a Quercus ilex Mediterranean forest. European Journal of Soil Biology 44: 509-520.
Sardans J, Peñuelas J, Ogaya R (2008) Drought-induced changes in C and N stoichiometry in a Quercus ilex Mediterranean forest . Forest Science 54: 513-522
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