نتایج جستجو برای: bees production
تعداد نتایج: 613288 فیلتر نتایج به سال:
We assessed the energetic and aerodynamic limits of hovering flight in the carpenter bee Xylocopa varipuncta. Using normoxic, variable-density mixtures of O(2), N(2) and He, we were able to elicit maximal hovering performance and aerodynamic failure in the majority of bees sampled. Bees were not isometric regarding thorax mass and wing area, both of which were disproportionately lower in heavie...
In many nectarless flowering plants, pollen serves as both the carrier of male gametes and as food for pollinators. This can generate an evolutionary conflict if the use of pollen as food by pollinators reduces the number of gametes available for cross-fertilization. Heteranthery, the production of two or more stamen types by individual flowers reduces this conflict by allowing different stamen...
The modern queens maintenance systems are based on the use of artificial insemination, queens’ maintenance in the so called „queens bank” , in this way assuring an increased economic efficiency in beekeeping. This study aimed to compare the economic efficiency of the implementation of A.I. to various queen bees maintenance systems. Three alternatives have been taken into account: V1-a queen bee...
The alfalfa leafcutting bee, Megachile rotundata F. (Hymenoptera: Megachilidae), is widely used as a pollinator for production of alfalfa, Medicago sativa L., seed, and populations of these bees can be maintained by alfalfa seed growers or can be purchased from mostly Canadian bee providers. M. rotundata raised in Canada have higher survival rates during the incubation that occurs after winter ...
Honey bees, as social insects, rely on collective behavioral defenses that produce a colony-level immune phenotype, or social immunity, which in turn impacts the immune response of individuals. One behavioral defense is the collection and deposition of antimicrobial plant resins, or propolis, in the nest. We tested the effect of a naturally constructed propolis envelope within standard beekeepi...
There is compelling evidence that more diverse ecosystems deliver greater benefits to people, and these ecosystem services have become a key argument for biodiversity conservation. However, it is unclear how much biodiversity is needed to deliver ecosystem services in a cost-effective way. Here we show that, while the contribution of wild bees to crop production is significant, service delivery...
We evaluated the ratio between the number of pollen foragers and the total number of bees entering colonies of Melipona bicolor, a facultative polygynous species of stingless bees. The variables considered in our analysis were: seasonality, colony size and the number of physogastric queens in each colony. The pollen forager ratios varied significantly between seasons; the ratio was higher in wi...
Pollen substitute diets are a valuable resource for maintaining strong and health honey bee colonies. Specific diets may be useful in one region or country and inadequate or economically unviable in others. We compared two artificial protein diets that had been formulated from locally-available ingredients in Brazil with bee bread and a non-protein sucrose diet. Groups of 100 newly-emerged, adu...
In diverse pollinator communities, interspecific interactions may modify the behaviour and increase the pollination effectiveness of individual species. Because agricultural production reliant on pollination is growing, improving pollination effectiveness could increase crop yield without any increase in agricultural intensity or area. In California almond, a crop highly dependent on honey bee ...
Neotropical orchid bees (Hymenoptera: Apidae: Euglossina) are conspicuous due to their vivid and metallic colors. Nevertheless, except for a few comments, usually concerning the appropriateness of using coloration as a taxonomic character (e.g. Rebêlo and Moure, 1996; Nemésio, 2005, 2009; Bembé, 2007), virtually nothing is known about color production and evolution in orchid bees. Based on stud...
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