Range expansion of the Bluetongue vector, Culicoides imicola, in continental France likely due to rare wind-transport events

The role of the northward expansion of Culicoides imicola Kieffer in recent and unprecedented outbreaks of Culicoides-borne arboviruses in southern Europe has been a significant point of contention. We combined entomological surveys, movement simulations of air-borne particles, and population genetics to reconstruct the chain of events that led to a newly colonized French area nestled at the northern foot of the Pyrenees. Simulating the movement of air-borne particles evidenced frequent wind-transport events allowing, within at most 36 hours, the immigration of midges from north-eastern Spain and Balearic Islands, and, as rare events, their immigration from Corsica. Completing the puzzle, population genetic analyses discriminated Corsica as the origin of the new population and identified two successive colonization events within west-Mediterranean basin. Our findings are of considerable importance when trying to understand the invasion of new territories by expanding species

Colonization of the Mediterranean Basin by the vector biting midge species Culicoides imicola: an old story

Understanding the demographic history and genetic make-up of colonizing species is critical for inferring population sources and colonization routes. This is of main interest for designing accurate control measures in areas newly colonized by vector species of economically important pathogens. The biting midge Culicoides imicola is a major vector of Orbiviruses to livestock. Historically, the distribution of this species was limited to the Afrotropical region. Entomological surveys first revealed the presence of C. imicola in the south of the Mediterranean basin by the 1970's. Following recurrent reports of massive bluetongue outbreaks since the 1990s, the presence of the species was confirmed in northern areas. In this study, we addressed the chronology and processes of C. imicola colonization in the Mediterranean basin. We characterized the genetic structure of its populations across Mediterranean and African regions using both mitochondrial and nuclear markers, and combined phylogeographical analyses with population genetics and approximate Bayesian computation. We found a west/east genetic differentiation between populations, occurring both within Africa and within the Mediterranean basin. We demonstrated that three of these groups had experienced demographic expansions in the Pleistocene, probably because of climate changes during this period. Finally, we showed that C. imicola could have colonized the Mediterranean basin in the late Pleistocene or early Holocene through a single event of introduction; however we cannot exclude the hypothesis involving two routes of colonization. Thus, the recent bluetongue outbreaks are not linked to C. imicola colonization event, but rather to biological changes in the vector or the virus

Differences of Soil Water Use, Lint and Biomass Yield in No-till and Conventionally Tilled Cotton in the Southern Piedmont

Proceedings of the 1999 Georgia Water Resources Conference, March 30 and 31, Athens, Georgia.The southeast, despite its abundant rainfall, suffers short-term summer droughts with detrimental effect on crop yield. No-till production systems provide added insurance against such conditions by improving infiltration, and conserving moisture in drought-prone soils. In three years of experiment near Watkinsville, GA, no-till cotton treatments maintained higher soil moisture content, more vegetative growth and higher lint yield than conventional tillage treatments. A combination of no-till and poultry litter treatments did even better compared to conventional tillage and conventional fertilizer treatments.Sponsored and Organized by: U.S. Geological Survey, Georgia Department of Natural Resources, The University of Georgia, Georgia State University, Georgia Institute of TechnologyThis book was published by the Institute of Ecology, The University of Georgia, Athens, Georgia 30602-2202 with partial funding provided by the U.S. Department of Interior, geological Survey, through the Georgia Water Research Insttitute as authorized by the Water Research Institutes Authorization Act of 1990 (P.L. 101-397). The views and statements advanced in this publication are solely those of the authors and do not represent official views or policies of the University of Georgia or the U.S. Geological Survey or the conference sponsors

ASTRID project, general overview and status progress

International audienceAfter 6 years of conceptual design phase, the French ASTRID project has started at the beginning of 2016, a 4 years basic design phase. The objective of this paper is to show and underline ASTRID progress and status and to give information of what we have intended for the next 2 years. The ASTRID project is based on a very efficient partnership, allowing versatility and manageability. Very high level and up-to-date project management methods are performed, including technical control with engineering System tools and 3D mock-up consolidation.All the industrials partners involved in the project during the last phase have decided to pursue in the ASTRID project, and the strategic partnership with Japan is going to be reinforced.ASTRID design has also evolved, taking into account new progresses on design to reach better consistency according to high level of reliability and safety, consistent with Generation IV objectives. A cost killing methodology is provided and feedbacks will be expected during 2018 and 2019 years. In the same time, an ongoing effort started two years ago is underway to map all the qualification needs and define all associated processes consistent with safety regulator requirement