International audience | The parasitic mite, Varroa destructor, has shaken the beekeeping and pollination industries since its spread from its native host, the Asian honey bee (Apis cerana), to the naïve European honey bee (Apis mellifera) used commercially for pollination and honey production around the globe. Varroa is the greatest threat to honey bee health. Worrying observations include increasing acaricide resistance in the varroa population and sinking economic treatment thresholds,suggesting that the mites or their vectored viruses are becoming more virulent. Highly infested weak colonies facilitate mite dispersal and disease transmission to stronger and healthier colonies. Here, we review recent developments in thebiology, pathology, and management of varroa, and integrate older knowledge that is less well known.

Both ecosystem function and agricultural productivity depend on services provided by bees; these services are at risk from bee declines which have been linked to land use change, pesticide exposure, and pathogens. Although these stressors often co-occur in agroecosystems, a majority of pollinator health studies have focused on these factors in isolation, therefore limiting our ability to make informed policy and management decisions. Here, we investigate the combined impact of altered landscape composition and fungicide exposure on the prevalence of chalkbrood disease, caused by fungi in the genus Ascosphaera Olive and Spiltoir 1955 (Ascosphaeraceae: Onygenales), in the introduced solitary bee, Osmia cornifrons (Radoszkowski 1887) (Megachilidae: Hymenoptera). We used both field studies and laboratory assays to evaluate the potential for interactions between altered landscape composition, fungicide exposure, and Ascosphaera on O. cornifrons mortality. Chalkbrood incidence in larval O. cornifrons decreased with high open natural habitat cover, whereas Ascosphaera prevalence in adults decreased with high urban habitat cover. Conversely, high fungicide concentration and high forest cover increased chalkbrood incidence in larval O. cornifrons and decreased Ascosphaera incidence in adults. Our laboratory assay revealed an additive effect of fungicides and fungal pathogen exposure on the mortality of a common solitary bee. Additionally, we utilized phylogenetic methods and identified four species of Ascosphaera with O. cornifrons, both confirming previous reports and shedding light on new associates. Our findings highlight the impact of fungicides on bee health and underscore the importance of studying interactions among factors associated with bee decline.

Dissertação de Mestrado Integrado em Medicina Veterinária | A Organização das Nações Unidas para a Alimentação e Agricultura (FAO) define a “Apicultura”, como a atividade que envolve o maneio de abelhas do mel em colmeias, para polinização, produção de mel, bem como de outros produtos apícolas. O praticar desta atividade pressupõe uma correta gestão e maneio do apiário, de forma a prevenir a ocorrência de doença, bem como a salvaguardar a obtenção de produtos de elevada qualidade para o consumidor. Tratando-se de uma atividade tradicionalmente ligada à agricultura, tem vindo a destacar-se pelo seu potencial próprio e, atualmente, é fortemente reconhecida a nível global. O presente estudo visou proceder a uma caracterização sanitária apícola, a nível nacional, no período compreendido entre Janeiro de 2015 e Dezembro de 2017, e realizar uma análise preliminar de estudo de fatores de risco para a ocorrência de doença ao nível de uma zona controlada (ZC), na região de Lisboa e Vale do Tejo. As ZC são espaços geográficos submetidos a um controlo sistemático de despiste de doenças da abelha melífera, ocupando cerca de metade do território continental. A maioria das análises anatomopatológicas efetuadas em Portugal (64 a 72% nos três anos em estudo) resultam de amostras recolhidas nestas zonas. Para o primeiro objetivo, utilizaram-se os dados da Direção Geral de Alimentação e Veterinária relativos à prevalência das doenças de declaração obrigatória nas diferentes zonas controladas (ZC), para a elaboração de mapas coropletos representativos da evolução do panorama sanitário. Os resultados obtidos permitem destacar uma diminuição de loque americana e um aumento ligeiro das restantes doenças, particularmente um aumento progressivo na prevalência de ascosferiose nas ZC da DSAVR Norte, no intervalo 2015-2017. O segundo objetivo implicou a realização de um estudo observacional analítico transversal para deteção de fatores de risco envolvidos na ocorrência de doença. Foi elaborado um questionário sobre maneio e sanidade apícola, com posterior aplicação a apicultores da ZC Melbandos (n=70). As variáveis foram submetidas a uma análise estatística descritiva, seguida de uma análise univariada, culminando na construção de modelos de regressão logística múltiplos. A análise univariada identificou (p<0,1) a troca de quadros entre colónias (OR=3,28) e a não desinfeção dos quadros com recurso a chamejamento (OR=2,76) como possíveis fatores de risco para a ocorrência de varroose. Em relação à nosemose, uma distância inferior a 400m do apiário vizinho (OR=3,0) e a não desinfeção do material apícola com recurso a fervura aparentaram constituir fatores de risco envolvidos na ocorrência de doença. A criação de um sistema de informação para a sanidade apícola e o uso de Sistemas de Informação Geográficos para mapear Portugal de acordo com o seu potencial apícola constituem ferramentas importantes para o desenvolvimento futuro do setor apícola. | ABSTRACT - The Food and Agriculture Organization of the United Nations (FAO) defines “Beekeeping” as an activity that involves the management of honeybees in combs, to pollinate and to produce honey, as well as, the other derived products. This activity implies an adequate management of the apiary, preventing occurrence of disease and safeguarding high quality products for consumption. Traditionally connected with agriculture, this activity starts to stand out by its own potential and, nowadays, its importance is widely recognized on a global scale. The present study aimed to proceed to a characterization on national bee health, between January of 2015 and December of 2017, and to do a preliminary study of risk factors associated with the occurrence of disease at the level of a controlled area (CA), in the region of Lisbon and Tagus Valley. CAs are submitted to systematic control in order to check for honey bee diseases, in fact, those areas occupy almost half of the continent territory, and the majority of the anatomopathological analysis on honey bees in Portugal (64% to 72% during the period from 2015 to 2017), results from samples collected in those regions. In order to carry out the first objetive, it was used the data from Portuguese National Authority for Animal Health on prevalence of notifiable diseases of honeybee in Portugal and in all 19 CAs, to perform choropleth maps representative of the evolution on the sanitary status. The results obtained allowed to highlight a decrease in american foulbrood and a slight increase in the other diseases, as well as, a progressive increase in the prevalence of chalkbrood in DSAVR North CAs, between 2015 and 2017. The second goal involved a cross-sectional study to check for risk factors implicated in the occurrence of disease. A sanitary management questionnaire was developed, with subsequent application to beekeepers of Melbandos CA (n=70). The variables were submitted to a descriptive statistical analysis, followed by an univariate analysis and finally culminating in the construction of logistic regression models. The univariate analysis identified (p<0,1) the exchange of frames between colonies (OR=3,28) and the non-disinfection of the beekeeping equipment the frames with flames (OR= 2,76), as possible risk factors for the occurrence of varroosis. Concerning nosemosis the distance between apiaries less than 400m (OR=3,0) and the non-disinfection of the frames by boiling appeared to be risk factors for the occurrence of disease. The creation of a bee health information system, as well as, the use of GIS technology to map Portugal according to its beekeeping aptitude would certainly be an useful tool to support the future development of the beekeeping sector. | N/A

Fungicides are applied to nearly 80% of U.S. melon acreage to manage the numerous foliar and fruit diseases that threaten yield. Chlorothalonil is the most widely used fungicide but has been associated with negative effects on human and bee health. We designed alternative fungicide programs to examine the impact of reducing chlorothalonil use (Bravo Weather Stik) on watermelon, cantaloupe, and honeydew melon in 2016, 2017, and 2018 in Maryland. Chlorothalonil was replaced in the tank mix of weekly sprays of targeted fungicides with either polyoxin D zinc salt (Oso) or an extract of Reynoutria sachalinensis (Regalia). Powdery mildew (PM; Podosphaera xanthii), gummy stem blight (GSB; Stagonosporopsis spp.), and anthracnose (Colletotrichum orbiculare) were the most prevalent diseases to occur in the 3 years. Replacing chlorothalonil with the biopesticides as the tank-mix component of the fungicide spray program was successful in reducing GSB and PM severity in cantaloupe, honeydew melon, and watermelon compared with the untreated control, with the exception of GSB in 2017 in cantaloupe, and similar to the program including chlorothalonil in all cases, except anthracnose in watermelon. Anthracnose disease severity was not significantly reduced compared with the untreated control when chlorothalonil was replaced with the biopesticides and yields were not improved over the chlorothalonil-alone treatment in any of the trials. Therefore, replacement of chlorothalonil may not fully address its loss as a fungicide resistance management tool but efficacy can be maintained when polyoxin D is alternated with R. sachalinensis as a tank mix with targeted fungicides to manage PM and GSB.