Geislingen an der Steige, Germany
Geislingen an der Steige, Germany

Time filter

Source Type

Costa C.,Italian Agricultural Research Council | Buchler R.,Bee Institute | Berg S.,Bayerische Landesanstalt fur Weinbau und Gartenbau | Bienkowska M.,Research Institute of Horticulture | And 23 more authors.
Journal of Apicultural Science | Year: 2012

An international experiment to estimate the importance of genotype-environment interactions on vitality and performance of honey bees and on colony losses was run between July 2009 and March 2012. Altogether 621 bee colonies, involving 16 different genetic origins of European honey bees, were tested in 21 locations spread in 11 countries. The genetic strains belonged to the subspecies A. m. carnica, A. m. ligustica, A. m. macedonica, A. m. mellifera, A. m. siciliana. At each location, the local strain of bees was tested together with at least two "foreign" origins, with a minimum starting number of 10 colonies per origin. The common test protocol for all the colonies took into account colony survival, bee population in spring, summer and autumn, honey production, pollen collection, swarming, gentleness, hygienic behaviour, Varroa destructor infestation, Nosema spp. infection and viruses. Data collection was performed according to uniform methods. No chemical treatments against Varroa or other diseases were applied during the experiment. This article describes the details of the experiment set-up and the work protocol.

Hatjina F.,Hellenic Institute of Apiculture | Costa C.,Italian Agricultural Research Council | Buchler R.,Bee Institute | Uzunov A.,Faculty for Agricultural Science and Food | And 21 more authors.
Journal of Apicultural Research | Year: 2014

Adaptation of honey bees to their environment is expressed by the annual development pattern of the colony, the balance with food sources and the host - parasite balance, all of which interact among each other with changes in the environment. In the present study, we analyse the development patterns over a period of two years in colonies belonging to 16 different genotypes and placed in areas grouped within six environmental clusters across Europe. The colonies were maintained with no chemical treatment against varroa mites. The aim of the study was to investigate the presence of genotype - environment interactions and their effects on colony development, which we use in this study as a measure of their vitality. We found that colonies placed in Southern Europe tend to have lower adult bee populations compared to colonies placed in colder conditions, while the brood population tends to be smaller in the North, thus reflecting the shorter longevity of bees in warmer climates and the shorter brood rearing period in the North. We found that both genotype and environment significantly affect colony development, and that specific adaptations exist, especially in terms of adult bee population and overwintering ability. © IBRA 2014 .

Costa C.,Italian Agricultural Research Council | Panasiuk B.,Research Institute of Horticulture | Meixner M.,Bee Institute | Kryger P.,University of Aarhus | And 14 more authors.
Journal of Apicultural Research | Year: 2014

Honey bee colonies exhibit a wide range of variation in their behaviour, depending on their genetic origin and environmental factors. The COLOSS Genotype-Environment Interactions Experiment gave us the opportunity to investigate the phenotypic expression of the swarming, defensive and hygienic behaviour of 16 genotypes from five different honey bee subspecies in various environmental conditions. In 2010 and 2011, a total of 621 colonies were monitored and tested according to a standard protocol for estimation of expression of these three behavioural traits. The factors: year, genotype, location, origin (local vs. non-local) and season (only for hygienic behaviour) were considered in statistical analyses to estimate their effect on expression of these behaviours. The general outcome of our study is that genotype and location have a significant effect on the analysed traits. For all characters, the variability among locations was higher than the variability among genotypes. We also detected significant variability between the genotypes from different subspecies, generally confirming their known characteristics, although great variability within subspecies was noticed. Defensive and swarming behaviour were each positively correlated across the two years, confirming genetic control of these characters. Defensive behaviour was lower in colonies of local origin, and was negatively correlated with hygienic behaviour. Hygienic behaviour was strongly influenced by the season in which the test was performed. The results from our study demonstrate that there is great behavioural variation among different subspecies and strains. Sustainable protection of local genotypes can be promoted by combining conservation efforts with selection and breeding to improve the appreciation by beekeepers of native stock. © IBRA 2014.

Francis R.M.,University of Aarhus | Kryger P.,University of Aarhus | Meixner M.,Bee Institute | Bouga M.,Agricultural University of Athens | And 14 more authors.
Journal of Apicultural Research | Year: 2014

The COLOSS GEI (Genotype-Environment Interactions) Experiment was setup to further our understanding of recent honey bee colony losses. The main objective of the GEI experiment was to understand the effects of environmental factors on the vitality of European honey bee genotypes. This paper aims to describe the genetic background and population allocation of the bees used in this experiment. Two wing morphometric and two genetic methods were employed to discriminate bee populations. Classical morphometry of 11 angles on the wings were carried out on 350 bees. Geometric morphometry on 19 wing landmarks was carried out on 381 individuals. DNA microsatellite analysis was carried out on 315 individuals using 24 loci. Allozyme analysis was performed on 90 individuals using six enzyme systems. DNA microsatellite markers produced the best discrimination between the subspecies (Apis mellifera carnica, A. m. ligustica, A. m. macedonica, A. m. mellifera and A. m. siciliana) used in the experiment. Morphometric methods generally showed an intermediate level of discrimination, usually best separating A. m. siciliana and A. m. ligustica from the remaining populations. Allozyme markers lack power to discriminate at the level of individual bees, and given our sample size, also fail to differentiate subspecies. Based on DNA microsatellites, about 69% of the individuals were assigned to the same subspecies as originally declared, and 17% were found to belong to a different subspecies. Fourteen percent of the samples were found to be of mixed origin and could not be assigned to any subspecies with certainty. We further discuss the caveats of the methods and details of the sampled bees, their origins and breeding programmes in their respective locations. © IBRA 2014.

Meixner M.D.,Bee Institute | Francis R.M.,University of Aarhus | Gajda A.,Warsaw University of Life Sciences | Kryger P.,University of Aarhus | And 20 more authors.
Journal of Apicultural Research | Year: 2014

Diseases are known to be one of the major contributors to colony losses. Within a Europe-wide experiment on genotype - environment interactions, an initial 621 colonies were set up and maintained from 2009 to 2012. The colonies were monitored to investigate the occurrence and levels of key pathogens. These included the mite Varroa destructor (mites per 10 g bees), Nosema spp. (spore loads and species determination), and viruses (presence/absence of acute bee paralysis virus (ABPV) and deformed wing virus (DWV)). Data from 2010 to the spring of 2011 are analysed in relation to the parameters: genotype, environment, and origin (local vs. non-local) of the colonies in the experiment. The relative importance of different pathogens as indicators of colony death within the experiment is compared. In addition, pathogen occurrence rates across the geographic locations are described. © IBRA 2014.

Buchler R.,Bee Institute | Costa C.,Italian Agricultural Research Council | Hatjina F.,Hellenic Institute of Apiculture | Andonov S.,Faculty for Agricultural Science and Food | And 15 more authors.
Journal of Apicultural Research | Year: 2014

The survival and performance of 597 honey bee colonies, representing five subspecies and 16 different genotypes, were comparatively studied in 20 apiaries across Europe. Started in October 2009, 15.7% of the colonies survived without any therapeutic treatment against diseases until spring 2012. The survival duration was strongly affected by environmental factors (apiary effects) and, to a lesser degree, by the genotypes and origin of queens. Varroa was identified as a main cause of losses (38.4%), followed by queen problems (16.9%) and Nosema infection (7.3%). On average, colonies with queens from local origin survived 83 days longer compared to non-local origins (p < 0.001). This result demonstrates strong genotype by environment interactions. Consequently, the conservation of bee diversity and the support of local breeding activities must be prioritised in order to prevent colony losses, to optimize a sustainable productivity and to enable a continuous adaptation to environmental changes. © IBRA 2014.

Buchler R.,Landesbetrieb Landwirtschaft Hessen | Berg S.,Bayerische Landesanstalt fur Weinbau und Gartenbau | Le Conte Y.,French National Institute for Agricultural Research
Apidologie | Year: 2010

The rich variety of native honeybee subspecies and ecotypes in Europe offers a good genetic resource for selection towards Varroa resistance. There are some examples of mite resistance that have developed as a consequence of natural selection in wild and managed European populations. However, most colonies are influenced by selective breeding and are intensively managed, including the regular use of miticides. We describe all characters used in European breeding programs to test for Varroa resistance. Some of them (e.g., mite population growth, hygienic behavior) have been implemented in large-scale selection programs and significant selection effects have been achieved. Survival tests of pre-selected breeder colonies and drone selection under infestation pressure are new attempts to strengthen effects of natural selection within selective breeding programs. Some perspectives for future breeding activities are discussed. © 2010 INRA/DIB-AGIB/EDP Sciences.

Neumuller M.,TU Munich | Muhlberger L.,TU Munich | Siegler H.,Bayerische Landesanstalt fur Weinbau und Gartenbau | Hartmann W.,Erikaweg 5 | Treutter D.,TU Munich
Acta Horticulturae | Year: 2013

A breeding program with the aim of obtaining Plum pox virus (PPV) resistant rootstocks for stone fruit cultivars was established at Technische Universität München. Genetic crosses between European plum (P. domestica) genotypes with hypersensitivity resistance to PPV were used as one parent and either P. spinosa or P. cerasifera as the other parent resulting in either 'Dospina' or 'Docera' rootstock candidates, respectively. The seedlings were screened for hypersensitivity resistance. The PPV resistant clones were screened for easy vegetative propagation by green cuttings, hardwood cuttings and in vitro propagation. The selected seedlings were retested extensively for PPV resistance with several European plum cultivars differing in their susceptibility to PPV. PPV infected budsticks of these cultivars were grafted onto the rootstock candidates either in spring or in summer. In many cases, the infected buds were rejected by the rootstock before bud break. Otherwise the young shoot which started to grow from the infected bud or budwood was rejected by the rootstock within several weeks after bud break. Due to this selfeliminating effect of PPV infected buds or scions grafted onto the newly developed PPV resistant rootstocks, no PPV infected tree developed to a marketable size. First results obtained from pomological tests indicate that trees grafted onto 'Docera 6' show similar vegetative and generative properties as those grafted onto 'St. Julien A' rootstock. National and international tests for the pomological evaluation of the rootstock are underway. In a first step, the new hypersensitive rootstocks will be used for newly bred hypersensitive plum cultivars. In this way, neither the rootstock nor the scion cultivar can get infected with PPV under natural inoculation conditions. This gives the highest level of security to damages caused by PPV which is available in stone fruits species at the moment. In a second step, their use for PPV sensitive European plum cultivars as well as for apricot, Japanese plum and peach is under evaluation.

Muller M.,Food and Beverage | Christoph N.,Food and Beverage | Wachter H.,Food and Beverage | Koehler H.-J.,Bayerische Landesanstalt Fur Weinbau und Gartenbau | Winterhalter P.,TU Braunschweig
ACS Symposium Series | Year: 2011

Due to the increasing consumer demand for oaked wines, wine makers have increased the production of such wines. The traditional method of aging wines in oak barrels (barrique), however is very expensive and it is more profitable to use an oak chips treatment. In the European Union the use of oak chips is restricted, e.g., in Germany for high quality wines. In general, wines labelled with barrel or barrique aging may not be treated with oak chips. For consumer protection and competitive distortions, it is necessary to have sophisticated analytical methods for authentication of barrel aged wines and to prove an oak chips treatment repectively. A method was developed using solid phase extraction (SPE) and gas chromatography-mass spectrometry for quantification of 20 volatile compounds in 138 authentic wines produced with both oenological practices. In a second approach SPE extracts of selected wines were analyzed with 1H-NMR to check for differences in the 1H-profiles of barrel aging and oak chips treatment. The data of both analytical methods were evaluated with multivariate methods using PCA and LDA. The first statistical models showed that a differentiation of both oenological practices was successful. © 2011 American Chemical Society.

Loading Bayerische Landesanstalt fur Weinbau und Gartenbau collaborators
Loading Bayerische Landesanstalt fur Weinbau und Gartenbau collaborators