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Bee pollinator toxicogenomics: an interdisciplinary approach to unravel molecular determinants of insecticide selectivity
Get PDFBee colony assessments with the Liebefeld method: How do individual beekeepers influence results and are photo assessments an option to reduce variability?
Get PDFColony strength, food storage and brood development are a fundamental part of each honeybee field study. Colony assessments are used to compare and assess those for beehive over time. At present, most colony assessments are made by experienced beekeepers according to Liebefeld method. This method is based on an estimation of areas covered by honeybees, food and brood stages on each side of a comb. Areas are counted from a grid separating the comb side into 8 sections which are protocolled with an accuracy of 0.5 sections. An assessment for a hive takes up to 20 min and even with two field locations, it is necessary to split assessments between beekeepers. So, it is important to make estimates as comparable as possible. For this purpose, beekeepers practice the assessments on pre-determined photographs to “calibrate themselves”. The advantage of the Liebefeld assessment is that the condition of bee hive is estimated with minimum disturbance of the bees. Digital photography is under discussion to gain data with high precision and accuracy with one major disadvantage. To be able to see food and brood stages in photographs, bees have to be removed from combs. This, however, results in a disturbance of the colony – especially if the assessments take place in short time intervals of 7 ± 1 days. An experiment was performed to evaluate the variation between individual beekeepers and to compare the results to data generated with photographs. For the experiment, five colonies were assessed each by four beekeepers independently according to Liebefeld method. Each comb side of the five colonies was photographed with and without honeybees sitting on it for precise analysis at the computer for a number of bees, nectar cells, pollen cells, eggs, open brood and capped brood. The number of bees and cells with the different contents were generated by an area-based assessment in ImageJ as well as a detailed counting with help of HiveAnalyzer® Software. Data from beekeeper estimations were then compared with assessments based on digital photography. With the results of the experiment, we tried to answer several questions. With the study, we wanted to determine the level of variation between the beekeepers for the live stages and food stores estimated.Colony strength, food storage and brood development are a fundamental part of each honeybee field study. Colony assessments are used to compare and assess those for beehive over time. At present, most colony assessments are made by experienced beekeepers according to Liebefeld method. This method is based on an estimation of areas covered by honeybees, food and brood stages on each side of a comb. Areas are counted from a grid separating the comb side into 8 sections which are protocolled with an accuracy of 0.5 sections. An assessment for a hive takes up to 20 min and even with two field locations, it is necessary to split assessments between beekeepers. So, it is important to make estimates as comparable as possible. For this purpose, beekeepers practice the assessments on pre-determined photographs to “calibrate themselves”. The advantage of the Liebefeld assessment is that the condition of bee hive is estimated with minimum disturbance of the bees. Digital photography is under discussion to gain data with high precision and accuracy with one major disadvantage. To be able to see food and brood stages in photographs, bees have to be removed from combs. This, however, results in a disturbance of the colony – especially if the assessments take place in short time intervals of 7 ± 1 days. An experiment was performed to evaluate the variation between individual beekeepers and to compare the results to data generated with photographs. For the experiment, five colonies were assessed each by four beekeepers independently according to Liebefeld method. Each comb side of the five colonies was photographed with and without honeybees sitting on it for precise analysis at the computer for a number of bees, nectar cells, pollen cells, eggs, open brood and capped brood. The number of bees and cells with the different contents were generated by an area-based assessment in ImageJ as well as a detailed counting with help of HiveAnalyzer® Software. Data from beekeeper estimations were then compared with assessments based on digital photography. With the results of the experiment, we tried to answer several questions. With the study, we wanted to determine the level of variation between the beekeepers for the live stages and food stores estimated
Interactive effects of the neonicotinoid Thiacloprid and two common fungicides on foraging performance and reproductive success of the solitary bee Osmia bicornis under field conditions
Get PDFCurrent achievements and future developments of a novel AI based visual monitoring of beehives in ecotoxicology and for the monitoring of landscape structures
Get PDFHoney bees are valuable bioindicators. As such, they hold a vast potential to help shed light on the extent and interdependencies of factors influencing the decline in the number of insects. However, to date this potential has not yet been fully leveraged, as the production of reliable data requires large-scale study designs, which are very labour intensive and therefore costly. A novel Artificial Intelligence (AI) based visual monitoring system could enable the partial automatization of data collection on activity, forager loss and impairment of the central nervous system. The possibility to extract features from image data could prospectively also allow an assessment of pollen intake and a differentiation of dead bees, drones and worker bees as well as other insects such as wasps or hornets. The technology was validated in different studies with regards to its scalability and its ability to extract motion and feature related information. The prospective possibilities were analyzed regarding their potential to enable advances both within ecotoxicological research and the monitoring of pollinator habitats.Honey bees are valuable bioindicators. As such, they hold a vast potential to help shed light on the extent and interdependencies of factors influencing the decline in the number of insects. However, to date this potential has not yet been fully leveraged, as the production of reliable data requires large-scale study designs, which are very labour intensive and therefore costly. A novel Artificial Intelligence (AI) based visual monitoring system could enable the partial automatization of data collection on activity, forager loss and impairment of the central nervous system. The possibility to extract features from image data could prospectively also allow an assessment of pollen intake and a differentiation of dead bees, drones and worker bees as well as other insects such as wasps or hornets. The technology was validated in different studies with regards to its scalability and its ability to extract motion and feature related information. The prospective possibilities were analyzed regarding their potential to enable advances both within ecotoxicological research and the monitoring of pollinator habitats
Interactions between Bombus terrestris and glyphosate-treated plants: are bees at risk of herbicide exposure?
Get PDFFlow cytometric investigations on Pelargonium × crispum: an estimation of nuclear DNA contents with two different internal standards
Get PDFSieben Pelargonium × crispum Sorten, vier Zuchtklone und die Art P. crispum wurden mit der Durchflusszytometrie untersucht. Für die Bestimmung der DNA-Gehalte wurden die zwei internen Standards Tomate ‘Stupické’ (2C-Wert = 1.96 pg) und Blumenkohl ‘Korso’ (2C-Wert = 1.31 pg) verwendet. Wie erwartet, unterschieden sich die 2C-Werte der untersuchten diploiden Genotypen signifikant von denen der tetraploiden. Insgesamt variierten die 2C-Werte zwischen 0.97 und 2.18 pg DNA und bildeten drei signifikant unterschiedliche Gruppen. Die ermittelten DNA-Gehalte waren unabhängig vom verwendeten Standard mit einer Ausnahme: der DNA-Gehalt der Art P. crispum gemessen mit ‘Korso‘ unterschied sich signifikant vom DNA-Gehalt, der mit ‘Stupické’ bestimmt wurde. Die Standards ‘Stupické’ und ‘Korso’ sind für durchflusszytometrische Untersuchungen von Genotypen mit 2C-Werten < 1.8 pg wie Diploide der Sektion Pelargonium gleichermaßen geeignet. Jedoch ist die Tomate ‘Stupické’ ein ungeeigneter Standard für Genotypen mit 2C-Werten von ca. 2 pg, weil sich die Positionen der 2C-Werte der Probe und des Standards überlappen.Seven Pelargonium × crispum cultivars, four breeding clones and the species P. crispum were analysed by flow cytometry. Tomato ‘Stupické’ (2C value = 1.96 pg) and cauliflower ‘Korso’ (2C value = 1.31 pg) were used as internal standards to estimate the DNA content of the samples. As expected, the 2C values of the investigated diploid and tetraploid genotypes discriminated significantly. Overall, the mean 2C values ranged from 0.97 to 2.18 pg DNA and formed three significantly different groups. The estimation of the DNA content of the cultivars and breeding clones was independent of the standard used with one exception; for P. crispum the estimated DNA contents differed significantly. The standards ‘Stupické’ and ‘Korso’ are equally appropriate for flow cytometric investigation of genotypes with 2C values < 1.8 pg like diploid genotypes of the section Pelargonium. Tomato ‘Stupické’ is a rather impractical standard for genotypes with 2C values of about 2 pg, due to the overlapping positions of the 2C values of sample and standard
National survey programmes – Responsibilities and challenges in the frame of the new plant health legislation
Get PDFMit in Kraft treten der neuen Pflanzengesundheitsverordnung (EU) 2016/2031 zum 14. Dezember 2019 haben sich die Anforderungen an Erhebungen auf geregelte Schadorganismen für die Mitgliedstaaten der Europäischen Union deutlich erhöht. Die Europäische Kommission unterstützt die Erhebungen in den Mitgliedstaaten über das Kofinanzierungssystem, welches in 2015 eingeführt wurde. Hierüber ist eine finanzielle Beteiligung der Europäischen Kommission bis zu 50 % der angefallenen Erhebungskosten für ausgewählte Schadorganismen möglich. Um die Gesamtheit der zukünftig verpflichtenden Erhebungen abdecken zu können, werden jedoch vor allem neue Verfahren und Technologien erforderlich sein.With the new plant health Regulation (EU) 2016/2031 coming into force on 14th December 2019, the requirements for surveys of regulated pests for the Member States of the European Union increased significantly. The survey activities in the Member States are supported by the European Commission by the co-financing system implemented in 2015. By this a financial contribution up to 50 % of the accumulated costs of the surveys of selected pests can be requested of the European Commission. For executing the entire obligatory future surveys, especially new methods and technologies will be necessary
The in vitro cultivation of Bursaphelenchus spp. at the reference laboratory for quarantine pests at Julius Kühn-Institut in Braunschweig
Get PDFDas Forstquarantänelabor des Julius Kühn-Instituts in Braunschweig (Deutschland) kuratiert eine einzigartige Sammlung lebender Bursaphelenchus-Arten, zudem Dauerpräparate und ITS-RFLP Muster dieser Arten. Die Sammlung wurde von Dr. Helen Braasch gegründet und umfasst derzeit 48 Arten in 305 verschiedenen Isolaten. Diese Isolate wurden über 30 Jahre hinweg weltweit aus verschiedenen Habitaten (Bäumen) und anderen Bezugsquellen, wie Holzimporten einschließlich Holzverpackungsmaterial, gesammelt. Die Aufzucht der Nematoden auf sporulierenden und nicht sporulierenden Botrytis cinerea – Kulturen ist anspruchsvoll, arbeitsintensiv und erfordert sowohl Erfahrung als auch Geduld.The Forest quarantine laboratory at Julius Kühn-Institut in Braunschweig (Germany) curates a unique collection of living Bursaphelenchus species, permanent slides and ITS-RFLP profiles. The collection was initiated by Dr. Helen Braasch and currently comprises 48 species in 308 different isolates. These isolates were collected over 30 years across the globe from various habitats and sources, like forest trees and wood imports including wooden packaging material. Cultivation of the nematodes on sporulating and non-sporulating Botrytis cinerea is sophisticated, labor-intensive and requires both, experience and patience