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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

The role of the queen in wax secretion and comb building in the Cape honeybee, Aps mellifera capensis (Escholtz)

Whiffler, Lynne Anne January 1992 (has links)
The role of the queen in wax secretion and comb building was studied in the the Cape honeybee, Apis mellifera capensis (Escholtz). The percentage of bees bearing wax and the amount of wax borne by these bees did not differ between the experiments. This meant that the queenless and queenright colonies had the potential to construct equal amounts of comb as the amounts of wax available for comb building was the same. Contrary to this prediction, queenright colonies constructed 8 times more comb than their queenless counterparts. Queenright Apis mellifera scutellata colonies constructed 4 times more comb than their queenless counterparts. The increased amount of 9-oxo-2-decanoic acid (90DA) in the A.m.capensis mandibular gland secretions could not alone account for this difference. In fact, A.m.capensis and A.m.scutellata colonies constructed similar amounts of comb when they were given their own queens or queens from the other race. Worker bees need to have direct contact with their queen for comb building to be enhanced. Even when the queen had her mandibular glands extirpated and tergite glands occluded large amounts of comb were constructed than when access to the queen was limited. Direct access to the head of a mated queen proved to be the stimulus enhancing comb building. No comb was constructed when the workers had access to the abdomen of the queen. Virgin queens did not stimulate comb building. The relatively large amounts of 90DA and 9HDA from the mandibular glands of Cape virgin queens had not influenced comb building. Worker sized cells were generally constructed. These cells were slightly smaller than those constructed by European honeybees, but were indicative of African bees. A few queen less colonies constructed cells that were of an intermediate drone and worker size. Four mandibular gland pneromones were measured by gas chromatography. No correlations between these pheromones and the comb construction measurements were found. It is unlikely that the mandibular gland pheromones are the only pheromones that stimulate comb building. Pheromones from other glands on the head may contribute towards the enhancement of comb building, and they are not present in virgin queens
32

Brood cycles in queenless colonies of Apis mellifera capensis

Crous, Kendall Lauren January 2010 (has links)
In a honeybee colony, the loss of a queen is considered to be a serious occurrence and, if a new queen is not produced, ultimately doomed. However, in colonies of Apis mellifera capensis (Cape honeybees), numerous pathways are available for a colony which unexpectedly losses a queen. At the onset of this experiment, four colonies of A. m. capensis were dequeened. Following this photographs of all brood frames in each colony were taken and the contents of the cells analysed. Cells were chosen at random but once selected were repeatedly analysed for the duration of the experiment. The contents of a total of 44 888 individual cells were analysed. Any queen cells constructed during the sampling period were removed, maintaining a queenless state. In each colony, as predicted, the removal of the queen evoked a variety of responses in an attempt to rectify the sudden loss. However, ultimately three of the four colonies absconded, leaving little by way of stores. Three of the four colonies initially attempted to rear a new queen while one colony was immediately invaded by a presumed foreign queen and hence any attempt at queen cell construction ceased. An increased number of queen cells in the swarm position were recorded in all colonies. The invasion of a colony by a foreign queen was considered to be a new pathway available for queenless colonies of A.m capensis. Worker policing and suspected brood cannibalism was prevalent in all sampled colonies yet in addition, the transfer of eggs and larvae from cell to cell was also observed which may have increased the suspected cases of policing and cannibalism. It was unclear whether an egg or larva had been consumed or simply moved to another cell on the brood frame. All colonies contained eggs from laying workers to varying degrees, based on the length of each individual sampling period which varied between colonies due to differences in absconding dates. A steady breakdown in the effectiveness of the division of labour amongst the worker bees was observed in each of the colonies highlighting the vital role of a queen. This breakdown was clearly seen in the reduction in general housekeeping within a colony. An increase in stores indicated a possible increase in the number of forager bees, thereby reducing the number of worker bees available for other duties. Pathways available to broodright colonies and strategies used following sudden queen loss are discussed.
33

Beekeeping for vocational agriculture students

Cheek, Ralph Bryant January 1949 (has links)
Much information is available in the field of Apiculture, some technical and some practical. It would appear, however, that there is justification for an attempt to provide information of a practical nature for use in high school Vocational Agricultural classes. Available publications either are too comprehensive or do not contain sufficient material for students of Vocational Agriculture who wish to study beekeeping. It is the intent of this thesis to consolidate and organize factual information for class use by teachers, to suggest a few student problems and activities, and to develop a course calendar of units for study. A detailed discussion of only one type of honey production is presented; but from this type (bulk-comb honey) any other form of honey production may be developed. / M.S.
34

A phenological and bioclimatic analysis of honey yield in South Africa

Illgner, Peter Mark January 2004 (has links)
This study has investigated the interaction between honeybees and their forage plants and the impact of selected climatic variables on honey production in South Africa. Twenty-seven scale-hive records from 25 localities have been used as a measure of colony honey reserves. At least 944 plant species are visited by honeybees in South Africa for their nectar and/or pollen, with more than half providing both rewards. The entire honeybee flora encompasses 532 genera and 137 families. The flowering phenologies of the different reward categories of the indigenous forage plants are all significantly and positively correlated at the 0.05 level. Similarly, species offering both rewards are significantly and positively correlated with the flowering phenology of the null flora. The same results were obtained for correlations between the different reward categories of the exotic forage plants in South Africa. Of the 30 species pairs which fulfilled the criteria for selection, 23 occurred in sympatry, 5 in allopatry and 2 in possible parapatry. There is evidence for both competition and facilitation within different indigenous species pairs. The lack of geographical correlation in the intra-annual variation in honey stores and the near absence of any statistically significant (p < 0.05) honey related intra-annual intracolonial correlations may indicate that the former is more important than the latter for the determination of the level of honey reserves within a colony. Only one statistically significant correlation was found between either scale-hive record from the University of Pretoria Experimental Farm and any of the selected climatic variables. A one month lag period and/or possible seasonal effects were detected for each variable, with the exception of the duration of sunshine, in the autocorrelation analyses. A possible 12 month seasonal period was also identified in the single series fourier analyses for a number of variables. Similarly, 12 months was also the most frequently recurring period in the crossspectral results for the one scale-hive record (H42). Any activities which have an impact on the landscape have the potential to affect honeybees and/or their forage plants. Honeybee crop or plant pollination may also enhance yields for commercial farmers and facilitate rural food security.
35

Learning commercial beekeeping: two cases of social learning in southern African community natural resources management contexts

Masara, Christopher January 2011 (has links)
Community Based Natural Resources Management (CBNRM) in southern Africa has gained an important role in alleviating poverty and conserving natural resources. The attention and funding CBNRM is receiving from governments, non-governmental organisations and donors is seen as one way to strengthen civil society‟s involvement in decision-making and participating in activities that contribute to a sustainable livelihood, whilst at the same time learning in their social contexts to adapt and care for the ever changing environment characterised by constraints, challenges, contradictions, new opportunities for learning and change. This study focuses on social learning in commercialisation of natural resource products in two case studies of commercial beekeeping in rural southern African contexts. In this study social learning entails a process of qualitative change taking place in a social context for the purpose of personal and social adaptation. This perspective is useful in this study as learning in the two cases, Hluleka in South Africa and Buhera in Zimbabwe involved the transition beekeeping.from traditional honey harvesting practices and subsistence beekeeping to commercial beekeeping. This study is informed by two related theoretical perspectives namely Cultural Historical Activity Theory (CHAT) and Social Learning Theory. CHAT was used as conceptual and methodological framework to inform the first phase of data gathering and analysis processes; as well as second phase data gathering. In the first phase, I gathered data through semistructured interviews, document reviews and observations to identify problems, challenges and critical incidents in learning commercial beekeeping, technically known as tensions and contradictions within the CHAT framework. These tensions and contradictions, surfaced through analysis of first phase data were used as "mirror data‟ in Intervention Workshops within CHAT's process of Developmental Work Research, which supports social learning in response to tensions and contradictions in workplace activity. Use of mirror data provided a basis for dialogue and the modelling of new solutions to identified contradictions. To interpret the social learning processes resulting from these interactions, I drew on Wals' (2007) analytical lenses, through which I was able to monitor social learning processes that emerged from the Intervention Workshop dialogues while beekeepers modelled new solutions to contradictions in learning commercial beekeeping. The findings of the study revealed that social learning in commercial beekeeping is internally and externally influenced by socio-cultural, political and economic complexities. Social learning in Intervention Workshops was supported by different knowledge bases of participants, in this study these are beekeepers, extension officers, trainers and development facilitators. Such knowledge bases were the source of information for learning and constructing model solutions. The study also revealed that learning in CBNRM workplaces can be observed across the development processes, and CHAT as a methodological tool and Wals‟ (2007) analytical tool are complementary and can be used in researching social learning in other CBNRM workplaces. The study contributes in-depth insight into participatory research and learning processes, especially within the context of CBRM in southern Africa. It gives some empirical and explanatory insight into how change-oriented social learning can emerge and be expanded in Education for Sustainable Development. It also provides learning and extension tools to work with contradictions that arise from socio-cultural and historical dimensions of learning commercialisation of natural resources in southern African context. Its other key contribution is that it provides further insight into the mobilisation of human agency and reflexivity in change oriented social learning processes of commercialisation of sustainable natural resources products and poverty alleviation processes that are critical for responding to socioecological issues and risks and development challenges in southern Africa.
36

Absence

Unknown Date (has links)
Absence is the thesis exhibition resulting from the culmination of my three years in the graduate program. In this documentation, I outline historical and contextual influences that shape my ceramic practice. I specify that my work is centered on my life and describe how my work has evolved since I first started in the program. In the process I have gathered source material and have explored key points in the theory and history of Minimalism. As I developed the work, I was able to discuss how my work applied to these sources, and where it differed. I ended with introspective installation work that paralleled the themes I was working with at the start of my graduate experience that shows my evolution from being a child continually bounced around from one family member to another, to being the confidant of my mother and holding her darkest secrets, to feeling alone and unloved, to finally beginning to heal and accept who I am. / Includes bibliography. / Thesis (M.F.A.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection
37

An assessment of honeybee foraging activity and pollination efficacy in Australian Bt cotton

Keshlaf, Marwan M. January 2008 (has links)
Thesis (Ph.D.)--University of Western Sydney, 2008. / A thesis submitted to the University of Western Sydney, College of Health and Science, Centre for Plant and Food Science, in fulfilment of the requirements for the degree of Doctor of Philosophy. Includes bibliography.
38

The occurrence of Nosema apis (Zander), Acarapis woodi (Rennie), and the Cape problem bee in the summer rainfall region of South Africa

Swart, Dawid Johannes January 2004 (has links)
The occurrence of Nosema disease, tracheal mites and the “pseudo-parasitic” behaviour of Cape honeybee workers when placed amongst African honeybees – known as the Cape Bee Problem – were studied over a 18 month period. Three surveys, approximately 6 months apart were done. The aims of this study were to establish the distribution and severity of the diseases and compare the disease with the presence of the Cape Bee Problem. Before this survey commenced European Foul Brood disease, Sacbrood (virus), Nosema, Brood nosema, and Tracheal mite have sporadically been reported in the summer rainfall region of South Africa. In the first survey 1005 colonies in 61 apiaries were surveyed, 803 colonies in 57 apiaries in the second, and 458 colonies in 41 apiaries in the third. Samples for disease and parasite analysis were taken at 4 colonies per apiary. Ten colonies per apiary were inspected for Cape Problem Bees, and samples of workers were collected and dissected at each of these colonies. Even with the addition of apiaries to 'fill-up' lost colonies during the second survey, 63% of all colonies were lost by the third survey. There was only a small difference in colony loss between sedentary and migratory beekeepers of 22% compared to 27%. Nosema was more prevalent amongst commercial beekeepers and increased in migratory operations during the survey period. The percentage of colonies infected increased during the survey period from 23% to 32% to 34%. The placement of colonies in Eucalyptus plantations may boost infection. Trachea mites seem to have spread quite rapidly in South Africa since its discovery. This parasitic mite was present in all regions, although in low numbers in three most northern regions. Sedentary colonies had higher levels of infestation than migratory colonies. The number of colonies infested diminished over the survey period, which may be a result of general colony loss. The Cape Problem Bee was less of a problem than anticipated. Colonies succumbed to Cape Problem Bees in all regions. When beekeepers reported high levels of infestation in their bee stocks the colonies would be dead within six months. In apiaries with low infestation the die-out was slower.
39

Studies on mixed-species colonies of honeybees, Apis cerana and Apis mellifera

Yang, Ming-Xian January 2010 (has links)
The honeybees Apis cerana and Apis mellifera are derived from the same ancestral base about two million years ago. With speciation and evolution, they have acquired many advanced living skills in common, but have also evolved very different living strategies due to different distributions. This thesis is an intensive study of the biology of the mixed-species colonies of these species, the aims of which were to investigate their behavioural relationships and uncover the evolutionary conserved features of their behaviours subsequent to speciation. The results show that the two species can form a stable society to perform normal tasks. First, workers of both species in the mixed-colonies could form the typical retinue behaviour to hetero-species queens, thus indicating that queen pheromones could be spread to and by both species. Secondly, both species did not show significantly different ovarian activation under hetero-species queens, suggesting that the queen pheromones more likely play a role of "honest signal" rather than a "repression" substance in the honeybee colonies. Thirdly, both species could mutually decode each other‘s waggle dances, with unexpectedly low misunderstanding; revealing that the dance language in a dark environment is quite adaptive for cavity-nesting honeybees. Fourthly, workers of both species could cooperate with each other in comb construction, although the combs they built contain many irregular cells. Interestingly, A. cerana workers could be stimulated by A. mellifera workers to perform this task, thus confirming self-organization theory in the colony. Fifthly, A. mellifera workers behaved more "defectively" in thermoregulation, but perhaps because A. cerana workers are more sensitive to changes in hive temperature. Given these differences in strategy, A. mellifera workers‘ performance might in fact reduce conflicts. Lastly, when faced with threats of predatory wasps, both species engaged in aggressive defence. Although they did not learn from each other‘s responses, species-specific strategies were adopted by each of them so that the defence of the mixed-colonies is very effective. I conclude that the two species can adapt to each other‘s efforts and task allocation is reasonably organized allowing mixed-species colonies to reach stability. These results suggest that all of the social behaviours discussed here were highly conserved following speciation. This thesis could provide some clues for the study of honeybee evolution from open-nesting to the transition of cavity-nesting.
40

Public private partnerships for the development of rural commercial beekeeping in the Amathole District Municipality

Musisi, Lawrence Ssensalire January 2016 (has links)
Beekeeping and Public Private Partnerships (PPP) are the key words in this study. The study investigates the effectiveness of the use of PPP for the development of commercial beekeeping for the small-scale beekeepers in selected rural areas of the Amathole District Municipality. The small-scale beekeepers do not seem to be achieving the required results of meeting market demands for honey and other bee by-products, due to challenges associated with production and marketing of these products. Significant investment (physical, human and financial) is required to develop the capacity of the small scale beekeepers in order to generate honey for the market and associated revenue in any significant quantity. While job creation and poverty alleviation are key issues on the government’s service delivery agenda, specifically through entrepreneurial development, government alone does not have the capacity to provide all the necessary resources for the establishment of commercial beekeeping to the resource-poor small-scale beekeepers. Based on the results of this study, all respondents (beekeepers and officials) in the study had a general understanding of “Public Private Partnerships”. However, the general interpretation of PPP was where government, business and civil society are working together in areas of mutual interest to achieve common or complementary goals than the regulated PPP arrangements guided by the specialized Treasury PPP Unit, whereby contractual obligation between different role players is paramount. In the context of small-scale beekeeping, all respondents were in support of type of PPP, whereby the association or partnership would involve the transfer of substantial financial, technical and operational risks. Besides the numerous limitations faced by the small-scale beekeepers in the running of their beekeeping operations, the study identified the following as the major factors believed to be compromising and limiting the proper functioning of PPP.

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