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Libčice nad Vltavou, Czech Republic

Kloucek P.,Czech University of Life Sciences | Smid J.,Czech University of Life Sciences | Flesar J.,Czech University of Life Sciences | Havlik J.,Czech University of Life Sciences | And 4 more authors.
Natural Product Communications | Year: 2012

This work evaluates the in vitro inhibitory activity of 70 essential oils (EOs) in the vapor phase for the control of Chalkbrood disease caused by Ascosphaera apis Maassen ex Claussen (Olive et Spiltoir). Two wild strains isolated from infected honey bee colonies together with one standard collection strain were tested by the microatmosphere method. From 70 EOs, 39 exhibited an antifungal effect against A. apis standard and wild strains. The greatest antifungal action was observed for EO vapors from Armoracia rusticana, followed by Thymus vulgaris, Cymbopogon flexosus, Origanum vulgare and Allium sativum. An investigation of chemical composition by GC-MS revealed, that the most active EOs contained allyl isothiocyanate, citral, carvacrol and diallyl sulfides as the main constituents. The chemical composition plays a key role, as activities of different EOs from the same botanical species were different according to their composition. Source

Hubert J.,Czech Republic Crop Research Institute | Kamler M.,Bee Research Institute at Dol | Nesvorna M.,Czech Republic Crop Research Institute | Ledvinka O.,Czech Hydrometeorological Institute | And 2 more authors.
Microbial Ecology | Year: 2016

The ectoparasitic mite Varroa destructor is a major pest of the honeybee Apis mellifera. In a previous study, bacteria were found in the guts of mites collected from winter beehive debris and were identified using Sanger sequencing of their 16S rRNA genes. In this study, community comparison and diversity analyses were performed to examine the microbiota of honeybees and mites at the population level. The microbiota of the mites and honeybees in 26 colonies in seven apiaries in Czechia was studied. Between 10 and 50 Varroa females were collected from the bottom board, and 10 worker bees were removed from the peripheral comb of the same beehive. Both bees and mites were surface sterilized. Analysis of the 16S rRNA gene libraries revealed significant differences in the Varroa and honeybee microbiota. The Varroa microbiota was less diverse than was the honeybee microbiota, and the relative abundances of bacterial taxa in the mite and bee microbiota differed. The Varroa mites, but not the honeybees, were found to be inhabited by Diplorickettsia. The relative abundance of Arsenophonus, Morganella, Spiroplasma, Enterococcus, and Pseudomonas was higher in Varroa than in honeybees, and the Diplorickettsia symbiont detected in this study is specific to Varroa mites. The results demonstrated that there are shared bacteria between Varroa and honeybee populations but that these bacteria occur in different relative proportions in the honeybee and mite bacteriomes. These results support the suggestion of bacterial transfer via mites, although only some of the transferred bacteria may be harmful. © 2016 Springer Science+Business Media New York Source

Erban T.,Czech Republic Crop Research Institute | Jedelsky P.L.,Charles University | Titera D.,Bee Research Institute at Dol
Apidologie | Year: 2013

Honeybee (Apis mellifera Linnaeus) colonies in temperate zones produce either summer bees, which have a lifespan of 15 to 48 days, or winter bees, which emerge in late summer and live up to 8 months. Winter bees develop unique physiological conditions characterized by changes in protein composition that appear to be major determinants of honeybee lifespan. We analyzed winter honeybee worker hemolymph using a proteomic approach for the first time. Hemolymph collected from the dorsal vessel of winter honeybees using a glass capillary tube was analyzed using two-dimensional gel electrophoresis followed by MALDI TOF/TOF protein identification. Overall, 93 spots were assigned significance (P < 0.05). Many identified proteins corresponded well with extended lifespan. Vitellogenin subunits (mainly ∼180 and ∼100 kDa) comprised the major portion of the proteins; however, vitellogenin dominance repressed the signals of the lower-abundance proteins. Future physiological studies related to overwintering bees, including health, immunity, longevity, nutrition, and/or colony losses, can benefit from these results. © 2013 INRA, DIB and Springer-Verlag France. Source

Ryba S.,Charles University | Ryba S.,Bee Research Institute at Dol | Kindlmann P.,Charles University | Kindlmann P.,Academy of Sciences of the Czech Republic | And 3 more authors.
Journal of Economic Entomology | Year: 2012

American foulbrood, because of its virulence and worldwide spread, is currently one of the most dangerous diseases of honey bees. Quick diagnosis of this disease is therefore vitally important. For its successful eradication, however, all the hives in the region must be tested. This is time consuming and costly. Therefore, a fast and sensitive method of detecting American foulbrood is needed. Here we present a method that significantly reduces the number of tests needed by combining batches of samples from different hives. The results of this method were verified by testing each sample. A simulation study was used to compare the efficiency of the new method with testing all the samples and to develop a decision tool for determining when best to use the new method. The method is suitable for testing large numbers of samples (over 100) when the incidence of the disease is low (10% or less). © 2012 Entomological Society of America. Source

Erban T.,Czech Republic Crop Research Institute | Petrova D.,Czech Republic Crop Research Institute | Harant K.,Charles University | Jedelsky P.L.,Charles University | And 2 more authors.
Apidologie | Year: 2014

Apis mellifera Linnaeus is a holometabolous insect that undergoes complete metamorphosis in its nonfeeding pupal stage before transitioning to the adult stage. Its pupal stages are classifiable by the unique color pigmentation of its compound eyes and thorax; notably, there is a red-eye stage involving an unpigmented body that has a relatively short duration and is easy to recognize. The aim of the current study was to create a proteomic reference map of the worker red-eye pupa hemolymph. Hemolymph was collected from dorsal vessels using glass capillary tubes and was examined using pI 3-10 two-dimensional gel electrophoresis (2DE; 10 and 14 %) and matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF)/TOF protein identification. This experimental approach allowed us to identify 129 different proteins organized into orthologous groups. Overall, the predominant category was post-translational modifications, protein turnover and chaperones (23.3 % of the identified proteins). In addition, we identified proteins in the non-orthologous groups of olfaction (2.3 % of the identified proteins) and storage hexamerins (3.1 % of the identified proteins). Quantitatively, the major protein isoforms that were accurately identified via 10 % 2DE were four forms of storage hexamerin: the 110, 70a, 70b, and 70c forms. The most abundant enzymes identified were short-chain dehydrogenases/reductases with pivotal developmental roles in ecdysteroidogenesis and a sigma class glutathione-S-transferase that most likely serves as a major protectant against the by-products of oxidative stress. Many of the identified proteins are known to be involved in the mechanisms of metamorphosis. All of the identified proteins are useful as markers for future comparative physiological and developmental studies. © 2013 INRA, DIB and Springer-Verlag France. Source

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