Genetic variability of the neogregarine apicystis bombi, an etiological agent of an emergent bumblebee disease

The worldwide spread of diseases is considered a major threat to biodiversity and a possible driver of the decline of pollinator populations, particularly when novel species or strains of parasites emerge. Previous studies have suggested that populations of introduced European honeybee (Apis mellifera) and bumblebee species (Bombus terrestris and Bombus ruderatus) in Argentina share the neogregarine parasite Apicystis bombi with the native bumblebee (Bombus dahlbomii). In this study we investigated whether A. bombi is acting as an emergent parasite in the non-native populations. Specifically, we asked whether A. bombi, recently identified in Argentina, was introduced by European, non-native bees. Using ITS1 and ITS2 to assess the parasite's intraspecific genetic variation in bees from Argentina and Europe, we found a largely unstructured parasite population, with only 15% of the genetic variation being explained by geographic location. The most abundant haplotype in Argentina (found in all 9 specimens of non-native species) was identical to the most abundant haplotype in Europe (found in 6 out of 8 specimens). Similarly, there was no evidence of structuring by host species, with this factor explaining only 17% of the genetic variation. Interestingly, parasites in native Bombus ephippiatus from Mexico were genetically distant from the Argentine and European samples, suggesting that sufficient variability does exist in the ITS region to identify continent-level genetic structure in the parasite. Thus, the data suggest that A. bombi from Argentina and Europe share a common, relatively recent origin. Although our data did not provide information on the direction of transfer, the absence of genetic structure across space and host species suggests that A. bombi may be acting as an emergent infectious disease across bee taxa and continents

Drainage observations in poorly drained soils in the Atlantic zone

9 fig. 5 tab. 2 ref. Sum. (En). Tambi?n como: Field Report - Atlantic Zone Programme (CATIE-AUW-MAG) no. 8

Determination of losses of nutrients and nematicides on a banana plantation in the Atlantic zone

15 fig. 18 tab. 3 ref. Sum. (En). Tambi?n como: Field Report - Atlantic Zone Programme (CATIE-AUW-MAG) no. 8

Voorkomen van het Zuiderzeekrabbetje <i>Rhithropanopeus harrisii</i> (Gould, 1841) in de Westerschelde

Five male specimens of the White-fingered Mud Crab Rhithropanopeus harrisii were collected from the intake screens of the nuclear power station at Doel on December 20th, 1991. These are the first living specimens of this species recorded in the Westernscheldt

Javana: A System for Building Customized Java Program Analysis Tools

Understanding the behavior of applications running on high-level language virtual machines, as is the case in Java, is non-trivial because of the tight entanglement at the lowest execution level between the application and the virtual machine. This paper proposes Javana, a system for building Java program analysis tools. Javana provides an easy-to-use instrumentation infrastructure that allows for building customized profiling tools very quickly. Javana runs

Découverte de deux puits antiques à Combas (Gard). Contribution à l'étude comparative des puits antiques dans la cité de Nîmes

Bessac Jean-Claude, Bletry-Sébé Sylvie, Bonnaud Roland, Maebe J., Thouzellier J.-P. Découverte de deux puits antiques à Combas (Gard). Contribution à l'étude comparative des puits antiques dans la cité de Nîmes. In: Revue archéologique de Narbonnaise, tome 17, 1984. pp. 187-222