Percorrer por autor "Martín-Hernández, Raquel"
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- Abelha melífera dos Açores: estudo epidemiológicaPublication . Lopes, Ana; Miranda, Joachim; Martín-Hernández, Raquel; Henriques, Dora; Pinto, M. AliceOs Açores são um local único para estudos epidemiológicos da abelha devido à distribuição heterogénea de um dos principais responsáveis pelo seu declínio mundial: Varroa destructor. Ademais, o fungo Nosema ceranae e vários vírus têm sido apontados como um problema sanitário. Assim, este é o primeiro estudo epidemiológico nos Açores para avaliar o estatuto da N. ceranae e os mais importantes vírus das abelhas: BQCV1, SBV2, CBPV3, LSV4, DWV5, AKI6 e BeeMLV7. Analisaram-se 474 amostras de oito das nove ilhas em 2014/2015 e 92 de quatro ilhas em 2020. O ADN e ARN foram extraídos e o diagnóstico e carga viral foram obtidos por RT-qPCR. Apenas Flores e Sta Maria não têm Nc, nas restantes ilhas a carga é variável, ocorrendo um aumento significativo em S. Jorge e Terceira em 2020. Os vírus BQCV e LSV estão em todas as ilhas amostradas sendo as cargas virais significativamente diferentes entre elas. Relativamente ao LSV, Flores apresentou a carga mais baixa e Pico a mais elevada. SBV existe apenas no Faial e Pico, sem diferenças nas cargas. CBPV tem prevalências baixas, tendo sido detetado no Pico, S. Miguel, Graciosa, Terceira, Faial, com cargas elevadas, à exceção de Graciosa e Pico. S. Jorge e Terceira não têm DWV, sendo que as restantes têm prevalências variáveis e cargas virais diferentes em ambos os anos. AKI e BeeMLV não foram detetados. Este estudo mostra que os Açores são um local privilegiado para a apicultura, com várias ilhas livres dos principais patógenos que afligem a abelha melífera no mundo.
- An unprecedented large-scale survey of honey bee mitochondrial diversity in Europe: c-lineage dominance and the need for conservation effortsPublication . Li, Fernanda; Costa, Maíra; Lopes, Ana Rita; Gonçalves, Telma; Henriques, Dora; Quaresma, Andreia; Yadró Garcia, Carlos A.; Albo, Alexandre; Blažytė-Čereškienė, Laima; Brodschneider, Robert; Brusbardis, Valters; Carreck, Norman L.; Charistos, Leonidas; Chlebo, Robert; Coffey, Mary F.; Dahle, Bjørn; Danneels, Ellen; Dobrescu, Constantin; Dupleix-Marchal, Anna; Filipi, Janja; Gajda, Anna; Gratzer, Kristina; Groeneveld, Linn Fenna; Hatjina, Fani; Johannesen, Jes; Kolasa, Michal; Körmendy-Rácz, János; Kovačić, Marin; Kristiansen, Preben; Martikkala, Maritta; McCormack, Grace P.; Martín-Hernández, Raquel; Pavlov, Borce; Pietropaoli, Marco; Poirot, Benjamin; Radev, Zheko; Raudmets, Aivar; René-Douarre, Vincent; Roessink, Ivo; Škerl, Maja Ivana Smodiš; Soland-Reckeweg, Gabriele; Titera, Dalibor; Van der Steen, Jozef; Varnava, Andri; Vejsnæs, Flemming; Webster, Matthew T.; Fedoriak, Mariia M.; Zarochentseva, Oksana; Graaf, Dirk C. de; Pinto, M. AliceEurope is home to ten Apis mellifera subspecies, which belong to three mitochondrial lineages: the Western European (M), Eastern European (C), and African (A). However, the long-standing human-mediated movement of queens, primarily of C-lineage ancestry, has threatened the genetic integrity of many of these native subspecies through introgression and replacement. This has led to the establishment of conservation programs to recover the native lines in some European countries. The maternally-inherited mitochondrial DNA (mtDNA), particularly the highly polymorphic intergenic region tRNAleu-cox2, has been the marker of choice for assessing honey bee variation and introgression at large geographical scales. Herein, we will show the results of the tRNAleu-cox2 variation obtained from over 1200 colonies sampled across the range of the ten subspecies and covering 33 European countries. These revealed that apart from a few countries (Portugal, Spain, and Ireland) and isolated protected populations, European populations are predominantly dominated by C-lineage haplotypes, and many native subspecies exhibit a signature of C-derived introgression. In conclusion, this unprecedented survey of honey bee diversity across Europe underscores the concerning dominance of C-lineage genetic variation, highlighting the urgent need for strategic conservation efforts to preserve the native genetic diversity of Apis mellifera.
- Applying reduce SNP assays for inferring C-lineage introgression patterns in Iberian honeybee populations of the Azores archipelagoPublication . Lopes, Ana; Neves, Cátia J.; Ferreira, Helena; Henriques, Dora; Quaresma, Andreia; Martín-Hernández, Raquel; Azevedo, João; Pinto, M. AliceThe genetic composition of the honeybee populations of the Macaronesian archipelago of the Azores is poorly known. Until now, only honeybee populations of the island of São Miguel have been surveyed for genetic variation through the use of the tRNAleu-cox2 intergenic mitochondrial DNA region and microsatellites. Here, we combine data from the mtDNA obtained with the DraI test (intergenic region) and from the nuclear DNA obtained with newly developed reduced SNP assays to provide a complete picture of introgression patterns in the Azorean honeybee populations at both mitochondrial and nuclear compartments. The sampling was carried out in 2014 and 2015 and comprised 474 colonies widely distributed across the 8 islands populated by honeybees. Our cyto-nuclear results show that C-derived introgression varies across the archipelago ranging from virtually pure populations of the Iberian honeybee in the island of Santa Maria (Q-values <5%) to highly introgressed populations in the island of Graciosa (Q-values>30%). The introgression levels are alarming and contrast with those of the Iberian honeybee populations of the mainland in Iberia, which are still virtually free of C-derived introgression, despite frequent importation of commercial queens.
- BeeHeal: promoting bee health for sustainable agriculturePublication . Martín-Hernández, Raquel; Lopes, Ana; Chevjanovsky, Nor; Dalmon, Anne; Higes, Mariano; Le Conte, Yves; Pinto, M. Alice; Reyes-Carreño, Maritza; Soroker, VictoriaDuring the last years there is an alarming increase in the collapse of honeybee colonies (Apis mellifera) where bee parasites and pathogens like Varroa destructor mites, the microsporidia Nosema ssp. and viruses have played the leading role. Colony decline might compromise not only food security but also present and future income to the growers. Hence, four institutions from Mediterranean area have joined forces to put toghether a project entitled, “BEEHEAL: Promoting bee health for sustainable agriculture”. BEEHEAL is a collaborative research between Centro de Investigación Apícola y Agroambiental de Marchamalo - CAR (Spain), Centre de recherche Provence-Alpes-Côte d’Azur Unité: Abeilles et Environnement - INRA (France), Agricultural Research Organization, The Volcani Center - ARO (Israel) and Mountain Research Center (CMO), Polytechnic Institute of Bragança (Portugal). The aim of this project is to determine the phenology and interaction of the microsporidia Nosema ceranae and viruses including acute bee paralysis virus (ABPV), Israeli acute paralysis virus (IAPV), Black queen cell virus (BQCV) Chronic bee paralysis virus (CBPV) and Deformed wing virus (DWV), in Spain, France, Portugal and Israel. The findings of this project, which involves an active and unique cooperation among partners representing Mediterranean countries which encompasses a wide range of environmental and beekeeping management conditions, will contribute to ameliorate the damage caused by the expansion of N. ceranae through a rational implementation of existing treatments to avoid emergence of synergistic pathogens that accelerate colony collapse compromising food security. This project started at 2017 and it will end in 2020. BEEHEAL is funded through the ARIMNet2 (2016) Call by the following funding agencies: INIA (Spain), ANR (France), MOARD (Israel), and FCT (Portugal). This presentation will detail the tasks that are ongoing in the BEEHEAL project.
- Beeheal: standardization of laboratory methods for sample processing, nucleic acids extraction and PCR for microsporidia and viruses analysisPublication . Martín-Hernández, Raquel; Benito, M.; Chejanovsky, Nor; Le Conte, Yves; Dalmon, Anne; Higes, Mariano; Pinto, M. Alice; Reyes-Carreño, Maritza; Soroker, VictoriaBEEHEAL is a project designed to determine the phenology and interaction of Nosema ceranae and viruses in four Mediterranean countries: Spain, France, Portugal and Israel, including some territories where Varroa destructor is not present (Azores and Ouessant islands). This will allow us to study and compare the interactions between pathogens in a wide range of hosts, beekeeping and climatic conditions. The honey bee samples collected along the year in the different countries will be analysed for pathogens in three laboratories. This requires a standardization of methods to compare the results in order to assign the effect of every variable in a reliable way. To that end, the participating laboratories have been working together to establish the sampling methodology, the conservation of the samples, the nucleic acids extraction and the PCR analysis. We analyzed the sample processing for nucleic acid extraction on TE buffer (with or without Proteinase K), CTAB buffer or commercial kits (Qiagen). The maceration of bees (either individually or in composite samples) in TE buffer and posterior incubation at 96ºC for 20 minutes showed a good sensibility level and good value for N. ceranae DNA extraction. This method also allowed the conservation of RNA at -80ºC for a month in the TE solution for later RNA extraction. A joint protocol for sample processing, DNA and RNA extraction and PCR analysis has been developed but adjusted to the particular conditions and equipment of each laboratory. The standardization of methods to be implemented by each participating laboratory will avoid the biases on conclusions based on the diverse methods applied.
- Beekeeping in the Mediterranean: a medibees survey on practices, trends and challengesPublication . Mangion, Marion Zammit; Martín-Hernández, Raquel; Nanetti, Antonio; Pinto, M. Alice; Noureddine, Adjlane; Anwer, Asmaa; Haddad, Nizar; Hosri, Chadi; Muz, Mustafa Necati; Daour, Ahmad Yousef; Sagastume, SoledadMEDIBEES is a PRIMA funded project that aims to identify honeybee colonies and subspecies that are most resilient to climate change and common pathogens throughout the Mediterranean region. Honeybees are critical to sustainable agricultural systems and the project aims to contribute to sustainability in the context of the increased desertification of the region due to climate change. As part of this project an intensive investigation of beekeeping was carried out within the consortium, with the objectives of 1) understanding the main practices in place, 2) identifying trends and challenges faced by beekeepers. This would help guide the consortium in framing research questions that are rooted in the requirements of the stakeholders. A questionnaire was therefore developed and circulated among beekeepers from Algeria, Egypt, Italy, Jordan, Lebanon, Malta, Portugal, Spain and Turkey in late June 2021. To date, over 1300 detailed responses have been collected. This study has yielded an important first profile of the nature of the apicultural industry for many of these participating countries. In this presentation, a description of the socio-demographics and the diverse management practice in place among beekeepers across the Mediterranean will be presented. In addition, important first-time data on the distribution of hives, the main sources of losses including current biotic and abiotic threats, the characteristics and ecological trends of both native and introduced honey bee subspecies in the different geographical regions will be described as experienced by the major stakeholders ie beekeepers. Finally, notably and overwhelmingly, beekeepers from the Mediterranean region list changes in weather patterns as the major factor affecting colony losses and profitability. This was followed closely by indiscriminant use of agricultural insecticides and urbanisation.
- Climate change-induced stress in the honey bee Apis mellifera L.- a genetic reviewPublication . Sagastume, Soledad; Cilia, Giovanni; Henriques, Dora; Yadró Garcia, Carlos A.; Corona, Miguel; Higes, Mariano; Pinto, M. Alice; Nanetti, Antonio; Martín-Hernández, RaquelClimate change is a powerful driver of stress, as it reinforces hotter and drier environments. For bees, the most concerning aspects of these new environmental conditions are the resistance and resilience of bees to changes in temperature, humidity and ultraviolet radiation, as well as the negative effect on diversity of food resources which can lead in nutritional stress. The climatic vulnerability of various bee species and subspecies varies worldwide, as they experience varying levels of stress and display distinct behaviors, weaknesses, and lifespans. To understand these differences, it is crucial to consider both the genetics and epigenetics of bees, as these factors play a key role in their response, resistance, and adaptation to new stressors. This review provides a guide of genetic and epigenetic markers involved in the cellular response of Apis mellifera to most common stressors derived from climate change. Understanding how the various molecular mechanisms interact to restore homeostasis during the stress response is essential for designing future studies based on molecular markers.
- Colonisation patterns of Nosema ceranae in the Azores ArchipelagoPublication . Lopes, Ana Rita; Martín-Hernández, Raquel; Higes, Mariano; Segura, Sara K.; Henriques, Dora; Pinto, M. AliceNosema ceranae is a highly prevalent pathogen of Apis mellifera, which is distributed worldwide. However, there may still exist isolated areas that remain free of N. ceranae. Herein, we used molecular tools to survey the Azores to detect N. ceranae and unravel its colonisation patterns. To that end, we sampled 474 colonies from eight islands in 2014/2015 and 91 from four islands in 2020. The findings revealed that N. ceranae was not only present but also the dominant species in the Azores. In 2014/2015, N. apis was rare and N. ceranae prevalence varied between 2.7% in São Jorge and 50.7% in Pico. In 2020, N. ceranae prevalence increased significantly (p < 0.001) in Terceira and São Jorge also showing higher infection levels. The spatiotemporal patterns suggest that N. ceranae colonised the archipelago recently, and it rapidly spread across other islands, where at least two independent introductions might have occurred. Flores and Santa Maria have escaped the N. ceranae invasion, and it is remarkable that Santa Maria is also free of Varroa destructor, which makes it one of the last places in Europe where the honey bee remains naive to these two major biotic stressors.
- Colonization patterns of Nosema ceranae in the Azores archipelagoPublication . Lopes, Ana; Segura, Sara K.; Martín-Hernández, Raquel; Henriques, Dora; Pinto, M. AliceNosema ceranae and Nosema apis are pathogens of honey bees that cause nosemosis, a disease implicated in colony losses worldwide. They are obligate intracellular pathogens infecting the midgut epithelial cells of adult honey bees. Although N. ceranae was originally a pathogen specific of Apis cerana, currently, it is found in Apis mellifera throughout most of the world. Due to their confined environments, which limited pathogen transmission and dissemination, islands are unique places for epidemiological studies. There are only a few Varroa destructor-free and possibly even fewer N. ceranae-free honey bee sanctuaries in the world, with the Azores being one. Even though with the exception of Santa Maria and Flores, nosemosis has been present in the Azores since 2008, the causal species has yet to be identified. Hence, this study aimed to determine the prevalence and infection levels of Nosema spp. in the Azorean honey bees. In 2014/2015, 474 colonies were sampled on Faial, Flores, Pico, Graciosa, São Jorge, São Miguel, Santa Maria, and Terceira. Additionally, São Jorge, Santa Maria, Faial, and Terceira were re-sampled in 2020 with a total of 91 colonies. DNA was extracted, and the diagnosis and Nosema spp. loads were obtained by multiplex PCR and RT-qPCR. The findings indicate that N. ceranae appears to be the dominant species in the Azores. N. apis was only detected in 2014/2015 with a very low prevalence (5.1%). N. ceranae prevalence varied between 2.7%, on São Jorge, and 50.7%, on Pico. In 2020, N. ceranae positive colonies increased significantly on Terceira (57.1%) and São Jorge (50.0%). N. ceranae was not detected on Santa Maria in both periods. Average infection levels in positive N. ceranae colonies were usually medium to high (>10-7 ng/μl), with São Jorge colonies displaying the greatest infection intensity (>10-5 ng/ μl). This study highlights the Azores archipelago as a unique place for beekeeping, with islands free of N. ceranae and V. destructor, which are two important stressors that afflict honey bees in the world.
- Conservation status of Apis mellifera ruttneri inferred from whole genome sequencesPublication . Pinto, M. Alice; Ariel Yadró, Carlos; Henriques, Dora; Zammit Mangion, Marion; Galea, Thomas; Farrugia, Dylan; Cilia, Giovanni; Noureddine, Adjlane; Rufino, José; Nanetti, Antonio; Martín-Hernández, RaquelApis mellifera ruttneri is the native honey bee subspecies from the Maltese islands (Malta, Comino and Gozo). This African-lineage subspecies is adapted to the harsh environmental conditions and to the limited forage season of these islands. For many years, it was considered highly hybridized, due to the large and sustained importation of foreign subspecies, especially A. m. ligustica, perceived by many beekeepers as superior or for commercial reasons. Recent studies based on morphometry and mitochondrial DNA have suggested the occurrence of A. m. ruttneri, particularly in the main island. Conservation initiatives and a breeding program have been developed, but to date its conservation status is not fully known. As part of the MEDIBEES project, here, over 50 A. m. ruttneri georeferenced colonies collected from across Malta, as well as 50 several reference subspecies (A. m. ligustica, A. m. siciliana, A. m. iberiensis, A. m. sahariensis, and A. m. intermissa) were whole genome sequenced. The population structure and admixture were assessed from genome-wide single nucleotide polymorphisms using model and distance based-methods. The results show varying levels of admixture proportions of A. m. ruttneri with C-lineage honey bees across Malta but also a shared ancestry with the honey bees of north Africa, consistent with the putative natural colonization from Africa in ancient times.