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Under 2014/15 var vi sammanlagt sju personer i den grupp på SLU som arbetar med olika aspekter på hälsa och sjukdomar hos honungsbin. Gruppen utökades under sommaren 2014 med två nya forskarstuderande/doktorander; Sepideh Lamei som ska studera mjölksyrabakteriers betydelse för bins hälsa, och Srinivas Thaduri som ska studera sammansättningen av mikroorganismer hos den gotländska population av bin som överlevt och klarar sig utan behandling mot varroakvalstret (de så kallade Bondbina). En kortfattad beskrivning av deras respektive projekt kan ni läsa om längre ned i texten.

It has been suggested that the widespread use of neonicotinoid insecticides threatens bees, but research on this topic has been surrounded by controversy. In order to synthesize which research approaches have been used to examine the effect of neonicotinoids on bees and to identify knowledge gaps, we systematically reviewed research on this subject that was available on the Web of Science and PubMed in June 2015. Most of the 216 primary research studies were conducted in Europe or North America (82%), involved the neonicotinoid imidacloprid (78%), and concerned the western honey bee Apis mellifera (75%). Thus, little seems to be known about neonicotinoids and bees in areas outside Europe and North America. Furthermore, because there is considerable variation in ecological traits among bee taxa, studies on honey bees are not likely to fully predict impacts of neonicotinoids on other species. Studies on crops were dominated by seed-treated maize, oilseed rape (canola) and sunflower, whereas less is known about potential side effects on bees from the use of other application methods on insect pollinated fruit and vegetable crops, or on lawns and ornamental plants. Laboratory approaches were most common, and we suggest that their capability to infer real-world consequences are improved when combined with information from field studies about realistic exposures to neonicotinoids. Studies using field approaches often examined only bee exposure to neonicotinoids and more field studies are needed that measure impacts of exposure. Most studies measured effects on individual bees. We suggest that effects on the individual bee should be linked to both mechanisms at the sub-individual level and also to the consequences for the colony and wider bee populations. As bees are increasingly facing multiple interacting pressures future research needs to clarify the role of neonicotinoids in relative to other drivers of bee declines.

Är GMO-grödor farliga för bin?

Under 2013 har SLUs bigård vid Hammarby avvecklats då marken skall säljas. Bigårdshuset, som var en relativt enkel byggnad uppfördes för ändamålet 1965 och var i stort behov av omfattande reparationer. Som ersättning har den praktiska delen av biverksamheten fått en egen byggnad mitt på Ultunas campus, med en fin placering i anslutning till den nyanlagda kunskapsparken.

Syftet med projektet var att undersöka förekomsten av växtskyddsmedel i bin och pollen från bikupor med olika närhet till jordbruksmark. Rester av växtskyddsmedel i terrester miljö är betydligt mindre studerade än resthalter i vattenmiljön. Honungsbin (Apis mellifera) och vaxkakor med pollen samlades in från 14 olika bisamhällen i 8 olika regioner i södra och mellersta Sverige under månadsskiftet maj/juni och i juli 2012, resulterande i totalt 28 biprover och 26 pollenprover. Analysmetoder för dessa komplexa provmatriser har utvecklats för bestämning av 78 växtskyddsmedel med vätskekromatografi kopplat till tandem masspektrometri (LC-MS/MS) och ytterligare 21 substanser med gaskromatografi kopplat till masspektrometri (GC-MS). I biproverna detekterades sammanlagt 21 av de undersökta substanserna och i insamlat pollen från pollenkakor detekterades 26 substanser. De allra flesta fynden uppvisade låga koncentrationer kring detektions- eller kvantifieringsgränserna för substanserna. Som mest detekterades 13 olika substanser i ett och samma biprov och 16 olika substanser i ett och samma pollenprov. De högsta uppmätta koncentrationerna i studien var för två svampmedel: 407 ng/g för prokloraz i pollen samt 309 och 42 ng/g för azoxystrobin i pollen respektive bin, alla insamlade från samma område i mellersta Skåne. Tre neonikotinoider, acetamiprid, klotianidin och tiakloprid detekterades i låga koncentrationer (10 ng/g eller lägre) i både bin och insamlat pollen. Mest frekvent förekommande var tiakloprid med 10 fynd i bin och 6 fynd i pollen. Vad gäller både koncentrationer och frekvens av de undersökta växtskyddsmedlen dominerade lokalerna i mellersta och södra Skåne. Generellt detekterades fler substanser vid den tidiga provtagningen i månadsskiftet maj/juni än vid provtagningen i juli. De utvecklade analysmetoderna för bin och av bin insamlat pollen har över lag låga detektionsgränser och skulle kunna användas både för bedömning av bisamhällens exponering för växtskyddsmedel och mer generellt för att studera vilka växtskyddsmedel som cirkulerar i den terrestra delen av odlingslandskapet och därmed har potential att den vägen spridas i ekosystemet. Provmängden som behövs är liten och bimetoden kan anpassas för analys av enskilda bin om behov finns.

Adult honey bees are maintained in vitro in laboratory cages for a variety of purposes. For example, researchers may wish to perform experiments on honey bees caged individually or in groups to study aspects of parasitology, toxicology, or physiology under highly controlled conditions, or they may cage whole frames to obtain newly emerged workers of known age cohorts. Regardless of purpose, researchers must manage a number of variables, ranging from selection of study subjects (e.g. honey bee subspecies) to experimental environment (e.g. temperature and relative humidity). Although decisions made by researchers may not necessarily jeopardize the scientific rigour of an experiment, they may profoundly affect results, and may make comparisons with similar, but independent, studies difficult. Focusing primarily on workers, we provide recommendations for maintaining adults under in vitro laboratory conditions, whilst acknowledging gaps in our understanding that require further attention. We specifically describe how to properly obtain honey bees, and how to choose appropriate cages, incubator conditions, and food to obtain biologically relevant and comparable experimental results. Additionally, we provide broad recommendations for experimental design and statistical analyses of data that arises from experiments using caged honey bees. The ultimate goal of this, and of all COLOSS BEEBOOK papers, is not to stifle science with restrictions, but rather to provide researchers with the appropriate tools to generate comparable data that will build upon our current understanding of honey bees.

Article first published online: 1 MAY 2012; International audience; Honey bee societies (Apis mellifera), the ectoparasitic mite Varroa destructor, and honey bee viruses that are vectored by the mite, form a complex system of host–parasite interactions. Coevolution by natural selection in this system has been hindered for European honey bee hosts since apicultural practices remove the mite and consequently the selective pressures required for such a process. An increasing mite population means increasing transmission opportunities for viruses that can quickly develop into severe infections, killing a bee colony. Remarkably, a few subpopulations in Europe have survived mite infestation for extended periods of over 10 years without management by beekeepers and offer the possibility to study their natural host–parasite coevolution. Our study shows that two of these “natural” honey bee populations, in Avignon, France and Gotland, Sweden, have in fact evolved resistant traits that reduce the fitness of the mite (measured as the reproductive success), thereby reducing the parasitic load within the colony to evade the development of overt viral infections. Mite reproductive success was reduced by about 30% in both populations. Detailed examinations of mite reproductive parameters suggest these geographically and genetically distinct populations favor different mechanisms of resistance, even though they have experienced similar selection pressures of mite infestation. Compared to unrelated control colonies in the same location, mites in the Avignon population had high levels of infertility while in Gotland there was a higher proportions of mites that delayed initiation of egg-laying. Possible explanations for the observed rapid coevolution are discussed.

International audience; Understanding the fundaments of colony losses and improving the status of colony health will require cross-cutting research initiatives including honeybee pathology, chemistry, genetics and apicultural extension. The 7th framework of the European Union requested research to empirically and experimentally fill knowledge gaps on honeybee pests and diseases, including 'Colony Collapse Disorder' and the impact of parasites, pathogens and pesticides on honeybee mortality. The interactions among these drivers of colony loss will be studied in different European regions, using experimental model systems including selected parasites (e.g. Nosema and Varroa mites), viruses (Deformed Wing Virus, Black Queen Cell Virus, Israeli Acute Paralysis Virus) and model pesticides (thiacloprid, τ-fluvalinate). Transcriptome analyses will be used to explore host-pathogen-pesticide interactions and identify novel genes for disease resistance. Special attention will be given to sublethal and chronic exposure to pesticides and will screen how apicultural practices affect colony health. Novel diagnostic screening methods and sustainable concepts for disease prevention will be developed resulting in new treatments and selection tools for resistant stock. Research initiatives will be linked to various national and international ongoing European, North- and South-American colony health monitoring and research programs, to ensure a global transfer of results to apicultural practice in the world community of beekeepers.

International audience

International audience