Producción de mielatos en colonias de abejas afectadas por el mal del río en Uruguay

In Uruguay, the excretions of the flatidae Epormenis cestri when located in sarandí colorado trees (Sebastiania schottiana) are the cause of the massive death of young honeybee larvae, a phenomenon that beekeepers call River disease. A strong income of honeydew is frequently observed in these affected colonies despite the con-tinuous loss of bees due to lack of replacement. The aim of this study was to determine a handling of the colonies that allows obtaining honeydew honey. Forty-eight colonies were transported to an apiary affected by River disease and were divided into 5 groups according to the following treatments: Group 1: regular honeydew har-vest, adding of brood and sugar syrup supply (N=10); Group 2: regular honeydew harvest and sugar syrup supply (N=10); Group 3: regular honeydew harvest and adding of brood (N=10); Group 4: regular honeydew harvest (N=10); Group 5: only one harvest of honeydew once the study had finished (N=8). The colonies from groups 1 and 3 produced the biggest amount of honeydew honey, averaging 32.0 and 28.6kg, respectively. The physicochemical analysis of honeydew honey showed characteristics of this product such as high electrical conductivity (0.98-1.14 mS/cm), diastase activity (>50%) and color (71-83 mm Pfund). This study provides the basis of a colony handling that allows beekeepers to obtain important harvests of a honeydew honey not yet known in the international market.En Uruguay, las excreciones de los flátidos Epormenis cestri, cuando se localizan en árboles de sarandí colo-rado (Sebastiania schottiana), causan mortalidad masiva de larvas jóvenes de abejas melíferas, fenómeno que los apicultores denominan «mal del río». Frecuentemente se observa una fuerte entrada de mielatos en las colonias afectadas a pesar del despoblamiento de abejas generado por la falta de reemplazo. El objetivo de este estudio fue determinar un manejo de las colonias que permita obtener mielatos. Se transportaron 48 colo-nias a un colmenar afectado por el mal del río y se dividieron en 5 grupos de acuerdo con el tratamiento: Grupo 1: cosecha regular de mielatos, adición de cría y suministro de jarabe de azúcar (N = 10); Grupo 2: cosecha regular de mielatos y suministro de jarabe de azúcar (N = 10); Grupo 3: cosecha regular de mielatos y adición de cría (N = 10); Grupo 4: cosecha regular de mielatos (N = 10); Grupo 5: solo una cosecha de mielatos una vez finalizadas las secreciones de E. cestri (N = 8). Las colonias de los grupos 1 y 3 produjeron la mayor cantidad de mielatos, con un promedio de 32,0 y 28,6 kg, respectivamente. El análisis fisicoquímico de los mielatos mostró características de este producto, como alta conductividad eléctrica (0.98-1.14 mS / cm), activi-dad diastasa (> 50%) y color (71-83 mm Pfund). Este estudio proporciona la base de un manejo de las colonias que permite a los apicultores obtener cosechas importantes de un mielato aún no conocido en el mercado internacional

Effect of sugar syrup on larval survival in honey bee colonies affected by River disease

La muerte masiva de larvas de abejas Apis mellifera que ocurre cuando las abejas colectan las excreciones del flátido Epormensis cestri es conocida como Mal del Río en Uruguay. Los apicultores que encuentran afectadas sus colonias en primavera verano deben trasladarlas hacia otras zonas para evitar pérdidas importantes por despoblamiento. Algunos apicultores han tratado de disminuir la pérdida de larvas suministrando jarabe de azúcar reportando resultados dispares. Para determinar en qué medida el aporte de jarabe de azúcar reducía la mortalidad larval se instalaron en un apiario afectado por el Mal del Río tres grupos de 10 colonias cada uno. A dos grupos se les suministró dos litros de jarabe de azúcar 1:1 (peso:volumen) en 6 oportunidades a lo largo de 19 días, a uno a través de un alimentador interno y a otro a través de un alimentador externo. El tercer grupo de colonias no recibió jarabe de azúcar. En ese periodo se estimó en cuatro oportunidades la viabilidad de la cría mediante análisis de fotografías. El jarabe de azúcar, independientemente del tipo de alimentador empleado, permitió que sobrevivieran 53-64 % de las larvas en la primera semana, pero estos valores decayeron rápidamente alcanzando 7 días después un máximo de 24 %. En las colonias control la mortalidad de la cría fue menor a 2 %. Estos resultados muestran que el efecto del jarabe de azúcar en la reducción de mortalidad larval es acotado y de corta duración, por lo que no se aconseja a los apicultores recurrir a este manejo en colonias afectadas por el Mal del Río.The massive larvae death of the honey bee Apis mellifera that occurs when the bees collect the excretions of the flatidae Epormensis cestri is known in Uruguay as River disease. The beekeepers that find their colonies affected during spring-summer must move them to a safe place to prevent significant losses due to depopulation. Some beekeepers have tried to reduce the loss of larvae by adding sugar syrup, reporting different results. In order to evaluate in what measure, if any, the sugar syrup reduced the larvae mortality, 3 groups of 10 colonies each were installed in an apiary infected by River disease. Two of these groups were given two liters of sugar syrup 1:1 (weight:volume) in 6 opportunities throughout 19 days, one of them through an internal feeder and the other through an external feeder. The third group of colonies did not receive sugar syrup. In this period, the viability of the brood was estimated four times through photographic analysis. The sugar syrup, regardless of the type of feeder used, allowed 53-64 % of the larvae to survive the first week, but these values quickly decreased, reaching after 7 days a maximum survival of 24 %. In the control colonies the brood mortality was below 2 %. These results show that the effect that sugar syrup has on larvae mortality is narrow and of short duration, so it is not advised that beekeepers resort to this practice in colonies affected by River disease.INIA: FPTA 32

Observations on the biology of Epormenis cestri, Berg, 1879 (Hemiptera, Flatidae)

En Uruguay Epormenis cestri, excreta un líquido dulce que es colectado por Apis mellifera provocando la enfermedad del Mal del Río, con impacto económico en la apicultura. Se describen los estadios de ciclo de vida, vegetación asociada y posibles organismos controladores biológicos de las poblaciones de este Flátido.In Uruguay, Epormenis cestri excretes a sweet liquid that is collected by Apis mellifera causing the Mal del Río disease, with an economic impact on beekeeping. The life cycle stages, associated vegetation and possible biological control organisms of the populations of Epormenis cestri are described

Characterization of varroa destructor mites in Cuba using mitochondrial and nuclear markers

Varroa destructor has been present in Cuba since 1996, but without the use of acaricidal infestation rates remain at very low levels. The presence of Korean haplotype mites was described in 2007, but there is no information regarding the introgression of the less virulent Japanese haplotype that could account for a low pathogenicity of the mite. In this research, we carried out molecular characterization of Cuban Varroa mites through mitochondrial DNA and hypervariable nuclear loci. We applied an alternative RFLP tech-nique and found that all the analyzed samples corresponded to Korean haplotypes. We analyzed the three STRs loci VD112, VD114 and VD016, previously described as highly variable and found new alleles in all of them, with an absolute allele size very different to those reported worldwide. We also detected genic and genotypic differentiation be-tween samples from two nearby locations (P=0.08). We also tested a new RFLP method for mite haplotype discrimination with an intra-reaction positive control of digestion

La Candelaria Ridge (NW Argentina) as a natural lab for the exploration of the geothermal system of Rosario de La Frontera: Methods and preliminary results

Within the scientific framework recently proposed by C.U.I.A. (Consorzio Universitario Italiano per l’Argentina) for the development of applied researches on the Argentina territory, several research groups, belonging to selected Italian and Argentina Universities, converged in the last year on the research line devoted to the “Sustainable development of future towns”. This contribution focuses on the preliminary results achieved by this collaboration among the Universities of Camerino, Jujuy, Roma Tre, Salta, Sapienza. The project focuses on the application of robust methodologies and the development of new ones to explore the geothermal potential of the area of Rosario de La Frontera (NW Argentina) located at the northern edge of La Candelaria Ridge, one of positively inverted structures cropping out between the provinces of Salta and Tucuman. It belongs to the Santa Barbara System of the Andes retro-wedge...Fil: Maffucci, R.. Università Roma Tre III; ItaliaFil: Caffe, Pablo Jorge. Universidad Nacional de Jujuy. Instituto de Geología Minera; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; ArgentinaFil: Corrado, Sveva. Università Roma Tre III; ItaliaFil: Invernizzi, Ciro. Università degli Studi di Camerino; ItaliaFil: Giordano, G.. Università Roma Tre III; ItaliaFil: Pierantoni, Pablo. Università degli Studi di Camerino; ItaliaFil: Viramonte, Jose Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; Argentina. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Instituto Geonorte; Argentin

La Candelaria Ridge (NW Argentina) as a natural lab for the exploration of the geothermal system of Rosario de La Frontera: Methods and preliminary results

Within the scientific framework recently proposed by C.U.I.A. (Consorzio Universitario Italiano per l’Argentina) for the development of applied researches on the Argentina territory, several research groups, belonging to selected Italian and Argentina Universities, converged in the last year on the research line devoted to the “Sustainable development of future towns”. This contribution focuses on the preliminary results achieved by this collaboration among the Universities of Camerino, Jujuy, Roma Tre, Salta, Sapienza. The project focuses on the application of robust methodologies and the development of new ones to explore the geothermal potential of the area of Rosario de La Frontera (NW Argentina) located at the northern edge of La Candelaria Ridge, one of positively inverted structures cropping out between the provinces of Salta and Tucuman. It belongs to the Santa Barbara System of the Andes retro-wedge...Fil: Maffucci, R.. Università Roma Tre III; ItaliaFil: Caffe, Pablo Jorge. Universidad Nacional de Jujuy. Instituto de Geología Minera; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; ArgentinaFil: Corrado, Sveva. Università Roma Tre III; ItaliaFil: Invernizzi, Ciro. Università degli Studi di Camerino; ItaliaFil: Giordano, G.. Università Roma Tre III; ItaliaFil: Pierantoni, Pablo. Università degli Studi di Camerino; ItaliaFil: Viramonte, Jose Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; Argentina. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Instituto Geonorte; Argentin

Parasites and RNA viruses in wild and laboratory reared bumble bees Bombus pauloensis (Hymenoptera: Apidae) from Uruguay

Bumble bees (Bombus spp.) are important pollinators insects involved in the maintenance of natural ecosystems and food production. Bombus pauloensis is a widely distributed species in South America, that recently began to be managed and commercialized in this region. The movement of colonies within or between countries may favor the dissemination of parasites and pathogens, putting into risk while populations of B. pauloensis and other native species. In this study, wild B. pauloensis queens and workers, and laboratory reared workers were screened for the presence of phoretic mites, internal parasites (microsporidia, protists, nematodes and parasitoids) and RNA viruses (Black queen cell virus (BQCV), Deformed wing virus (DWV), Acute paralysis virus (ABCV) and Sacbrood virus (SBV)). Bumble bee queens showed the highest number of mite species, and it was the only group where Conopidae and S. bombi were detected. In the case of microsporidia, a higher prevalence of N. ceranae was detected in field workers. Finally, the bumble bees presented the four RNA viruses studied for A. mellifera, in proportions similar to those previously reported in this species. Those results highlight the risks of spillover among the different species of pollinators.Fil: Salvarrey, Sheena. Universidad de la República. Facultad de Ciencias; UruguayFil: Antúnez, Karina. Instituto de Investigaciones Biológicas "Clemente Estable"; UruguayFil: Arredondo, Daniela. Instituto de Investigaciones Biológicas "Clemente Estable"; UruguayFil: Plischuk, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Revainera, Pablo Damian. Universidad Nacional de Mar del Plata. Facultad de Cs.exactas y Naturales. Instituto de Investigaciones En Sanidad Produccion y Ambiente. - Comision de Investigaciones Cientificas de la Provincia de Buenos Aires. Instituto de Investigaciones En Sanidad Produccion y Ambiente.; ArgentinaFil: Maggi, Matías Daniel. Universidad Nacional de Mar del Plata. Facultad de Cs.exactas y Naturales. Instituto de Investigaciones En Sanidad Produccion y Ambiente. - Comision de Investigaciones Cientificas de la Provincia de Buenos Aires. Instituto de Investigaciones En Sanidad Produccion y Ambiente.; ArgentinaFil: Invernizzi, Ciro. Universidad de la República. Facultad de Ciencias; Urugua

Características del fruto de tomate (Solanum lycopersicum) utilizando abejorros nativos (Bombus atratus) como polinizadores en invernáculo

In Uruguay, the production of tomato (Solanum lycopersicum) in greenhouse presents pollination issues that limit its yield. The use of bumblebees (Bombus spp.) as pollinators can help overcome this problem as they perform “buzzing pollination”, a behavior that makes them excellent pollinators of Solanaceae and particularly tomato. The aim of this study was to evaluate the effect of the native bumblebees Bombus atratus on the pro-portion of fruit set, weight, diameter, number of seeds and number of locules of tomato (LAPATAIA and ELPIDA varieties). An experience was carried out in Canelones, where the fruits from flowers pollinated by bumblebees and from flowers not visited by insects were compared; two other experiences carried out in Salto were similar to that of Canelones, but included flowers treated with hormones. In the three analyzed greenhouses the visit of bumblebees to the flowers increased the proportion of fruit set by 13 - 47%, compared to the result obtained in flowers not visited by the insects. Also, the pollinating action of bumblebees significantly improved the weight, size, and number of seeds compared to fruits obtained from flowers without access to pollinators. This improve-ment was recorded in the experience in Canelones and only in one of the Salto's experiences. On the other hand, a positive correlation was found between the number of seeds and the weight (R2 = 0.37, R2 = 0.53; LAPATAIA, ELPIDA, respectively) in the two tomato varieties. This study is the first in Uruguay to show the benefits of using native bumblebees in tomato production in greenhouses.En Uruguay, la producción de tomate (Solanum lycopersicum) bajo invernáculo presenta problemas de polini-zación que limitan su rendimiento. El uso de abejorros (Bombus spp.) como polinizadores puede contribuir a superar este problema, ya que realizan «polinización por zumbido», comportamiento necesario para polinizar las solanáceas y particularmente el tomate. El objetivo de este estudio fue evaluar el efecto de los abejorros nativos Bombus atratus en el porcentaje de cuajado, peso, diámetro, número de semillas y número de lóculos de tomate (variedades LAPATAIA y ELPIDA). Se realizó una experiencia en el departamento de Canelones donde se cotejaron los frutos de flores polinizadas por abejorros y flores no visitadas por los insectos; y dos experiencias en Salto iguales a la de Canelones, pero que incluían flores tratadas con hormonas. En los tres invernáculos la visita de los abejorros a las flores incrementó el porcentaje de cuajado entre 13 y 47 % en relación con el obtenido en flores no visitadas por los insectos. La acción polinizadora de los abejorros también mejoró signifi-cativamente el peso, tamaño y número de semillas respecto a frutos obtenidos de flores sin acceso a poliniza-dores en dos de las tres experiencias realizadas. Por otro lado, en las dos variedades de tomate se encontró una correlación positiva entre el número de semillas y el peso (R2=0,37, R2=0,53; LAPATAIA, ELPIDA, respectiva-mente). Este estudio es el primero en Uruguay que muestra los beneficios de utilizar abejorros nativos para mejorar la producción de tomates en invernáculos

Impact of Nutritional Stress on Honeybee Gut Microbiota, Immunity, and Nosema ceranae Infection

Honeybees are important pollinators, having an essential role in the ecology of natural and agricultural environments. Honeybee colony losses episodes reported worldwide and have been associated with different pests and pathogens, pesticide exposure, and nutritional stress. This nutritional stress is related to the increase in monoculture areas which leads to a reduction of pollen availability and diversity. In this study, we examined whether nutritional stress affects honeybee gut microbiota, bee immunity, and infection by Nosema ceranae, under laboratory conditions. Consumption of Eucalyptus grandis pollen was used as a nutritionally poor-quality diet to study nutritional stress, in contraposition to the consumption of polyfloral pollen. Honeybees feed with Eucalyptus grandis pollen showed a lower abundance of Lactobacillus mellifer and Lactobacillus apis (Firm-4 and Firm-5, respectively) and Bifidobacterium spp. and a higher abundance of Bartonella apis, than honeybees fed with polyfloral pollen. Besides the impact of nutritional stress on honeybee microbiota, it also decreased the expression levels of vitellogenin and genes associated to immunity (glucose oxidase, hymenoptaecin and lysozyme). Finally, Eucalyptus grandis pollen favored the multiplication of Nosema ceranae. These results show that nutritional stress impacts the honeybee gut microbiota, having consequences on honeybee immunity and pathogen development. Those results may be useful to understand the influence of modern agriculture on honeybee health.Fil: Castelli, L.. Instituto de Investigaciones Biológicas "Clemente Estable"; UruguayFil: Branchiccela, B.. Instituto de Investigaciones Biológicas "Clemente Estable"; UruguayFil: Garrido, Paula Melisa. Universidad Nacional de Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente; ArgentinaFil: Invernizzi, Ciro. No especifíca;Fil: Porrini, Martín Pablo. Universidad Nacional de Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente; ArgentinaFil: Romero, H.. No especifíca;Fil: Santos, E.. No especifíca;Fil: Zunino, P.. Instituto de Investigaciones Biológicas "Clemente Estable"; UruguayFil: Antúnez, Karina. Instituto de Investigaciones Biológicas "Clemente Estable"; Urugua

Increased caspase-3 immunoexpression and morphology alterations in oenocytes and trophocytes of Apis mellifera larvae induced by toxic secretion of Epormenis cestri

Toxic honeydew produced by Flatidae Epormenis cestri in Uruguay has been shown to cause among honeybees (Apis mellifera) colonies a massive larva death called “River disease”, but the intrinsic mechanisms are still unknown. Because fat body cells, oenocytes and trophocytes, are known to regulated larvae metabolism, and to be affected by xenobiotics, we tested whether apoptosis of these cells can be an underlying cause of larvae death. Ten colonies were divided into two groups and fed with common honey or toxic honeydew obtained from colonies affected by “River disease”. Five-day-old larvae were collected and processed for histology and immunohistochemistry for caspase-3. The area, diameter, and immunostaining area in oenocytes and trophocytes were measured. The oenocyte and trophocyte cellular area decreased in the treated group (p=0.002; p<0.001 respectively) compared to the control group. The diameter of oenocytes (p=0.0002) and trophocytes (p<0.0001) decreased in the treated group. Caspase-3 was detected in cytoplasm in the control group but in the cytoplasm and nucleus in the treated group. The caspase-3 immunostaining area increased in oenocytes (p<0.002) and trophocytes (p<0.0001) of the treated group. The ingestion of toxic honeydew altered the morphology, localization and immunoexpression of caspase-3 in fat body cells, which suggests that the deregulation of the apoptotic mechanism affected the normal development in A. mellifera larvae