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Worker Bees (worker + bee)
Selected AbstractsThe Consumer Revolution in Urban China; Japanese Consumer Behavior: From Worker Bees to Wary ShoppersAMERICAN ETHNOLOGIST, Issue 4 2001Hai Ren The Consumer Revolution in Urban China. Deborah S. Davis, ed. Berkeley: University of California Press, 2000. xiii + 366 pp., illustrations, tables, photographs, bibliography, index. Japanese Consumer Behavior: From Worker Bees to Wary Shoppers. John McCrcery Honolulu: University of Hawai'i Press, 2000. ix + 278 pp., illustrations, photographs, bibliography, index. [source] Management of Braula orientalis Örösi (Diptera: Braulidae) in honeybee colonies with tobacco smoke under semiarid conditionsENTOMOLOGICAL RESEARCH, Issue 3 2009Abd Al-Majeed AL GHZAWI Abstract In the present study, bee colonies were smoked with tobacco smoke in order to evaluate the monthly changes in the numbers of worker bees, the infestation rates of worker bees and queens with bee lice, and the annual average honey production per colony. In July of each year, 12 colonies were smoked with tobacco smoke; the remaining hives not smoked with tobacco smoke served as the control. The results indicated that the applications of tobacco smoke during July gave rise to an impressive reduction in the Braula infestation rate on workers (below 1.8%) and reduced the amount of bee lice on the queen to zero throughout the 2,3 months following smoke treatment. In the colonies not treated with smoke, the Braula infestation rates on worker bees started to increase in May and continued to increase constantly during the rest of year, reaching maximum infestation rates of 28.2% and 33.8% in December, with an average of 15 and 17 lice per queen in November in the first and second years, respectively. Worker bee populations peaked in April and July of each year in both treatments. The average honey production per colony was significantly higher in the colonies treated with smoke than those that were not for the first and second years. In conclusion, early summer months may be the crucial time to smoke the colonies with tobacco smoke in order to keep bee lice at low levels for the remaining seasons. [source] Discrepancy between acute and chronic toxicity induced by imidacloprid and its metabolites in Apis melliferaENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 11 2001Séverine Suchail Abstract Imidaclopridi a systemic nitroguanidine insecticide that belongs to theneonicotinoid family. As an agonist of the acetylcholine receptor, it attacks the insect nervous system and is extremely effective against various sucking and mining pests. Oral acute and chronic toxicity of imidacloprid and its main metabolites (5-hydroxyimidacloprid, 4,5-dihydroxyimidacloprid, desnitroimidacloprid, 6-chloronicotinic acid, olefin, and urea derivative) were investigated in Apis mellifera. Acute intoxication by imidacloprid or its metabolites resulted in the rapid appearance of neurotoxicity symptoms, such as hyperresponsiveness, hyperactivity, and trembling and led to hyporesponsiveness and hypoactivity. For acute toxicity tests, bees were treated with doses of toxic compounds ranging from 1 to 1,000 ng/bee (10,10,000 ,g/kg). Acute toxicity (LD50) values of imidacloprid were about 60 ng/bee (600 ,g/kg) at 48 h and about 40 ng/bee (400 ,g/kg) at 72 and 96 h. Out of the six imidacloprid metabolites tested, only two (5-hydroxyimidacloprid and olefin) exhibited a toxicity close to that of imidacloprid. Olefin LD50 values were lower than those of imidacloprid. The 5-hydroxyimidacloprid showed a lower toxicity than imidacloprid with a LD50 four to six times higher than that of imidacloprid. Urea also appeared as a compound of nonnegligible toxicity by eliciting close to 40% mortality at 1,000 ng/bee (10,000 ,g/kg). However, no significant toxicity was observed with 4,5-dihydroxyimidacloprid, 6-chloronicotinic acid, and desnitroimidacloprid in the range of doses tested. To test chronic toxicity, worker bees were fed sucrose solutions containing 0.1, 1, and 10 ,g/L of imidacloprid and its metabolites for 10 d. Fifty percent mortality was reached at approximately 8 d. Hence, considering that sucrose syrup was consumed at the mean rate of 12 ,l/d and per bee, after an 8-d period the cumulated doses were approximately 0.01, 0.1, and 1 ng/bee (0.1, 1, and 10 ,g/kg). Thus, all tested compounds were toxic at doses 30 to 3,000 (olefin), 60 to 6,000 (imidacloprid), 200 to 20,000 (5-OH-imidacloprid), and >1,000 to 100,000 (remaining metabolites) times lower than those required to produce the same effect in acute intoxication studies. For all products tested, bee mortality was induced only 72 h after the onset of intoxication. [source] Expression and characterization of ,-glucosidase III in the dwarf honeybee, Apis florea (Hymenoptera: Apoidea: Apidae)INSECT SCIENCE, Issue 4 2007CHANPEN CHANCHAO Abstract Alpha-glucosidase is synthesized in the hypopharyngeal glands located in the head of worker bees including Apis florea. To analyze the developmental stage-specific expression of the ,-glucosidase gene in A. florea, total RNA was isolated from eggs, and the heads of nurse and forager bees. By reverse transcription polymerase chain reaction (RT-PCR), it was shown that the highest expression levels of the ,-glucosidase III gene, in the three examined developmental stadia, were found in forager bees, with much lower expression levels in nurse bees and no detectable expression in eggs. A complete ,-glucosidase III cDNA was obtained by RT-PCR and sequenced. The 1 701 bp cDNA nucleotide sequence and the predicted 567 amino acids it encodes were assayed by BLASTn, BLASTp and BLASTx programs and revealed a 95% and 94% similarity to the A. mellifera,-glucosidase III gene at the DNA and amino acid sequence levels, respectively. For purification of the active encoded enzyme, forager bee heads were homogenized in sodium phosphate buffer solution and the crude extract (0.30 U/mg) sequentially precipitated with 95% saturated ammonium sulfate (0.18 U/mg), and purified by DEAE cellulose ion exchange chromatography (0.17 U/mg), and gel filtration on Superdex 200 (0.52 U/mg). After resolution through sodium dodecyl sulfate-polyacrylamide gel electrophoresis, a single enzymically active band (73 kDa) was identified from renatured substrate gels. Excision of this band, elution of the protein and tryptic peptide digestives identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) revealed six matching masses to the A. mellifera (Q17958) and predicted A. florea,-glucosidase III protein with 12% coverage, supporting the probable purification of the same ,-glucosidase III protein as that encoded by the cloned cDNA. [source] Lethal and sub-lethal effects of spinosad on bumble bees (Bombus impatiens Cresson)PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 7 2005Lora A Morandin Abstract Recent developments of new families of pesticides and growing awareness of the importance of wild pollinators for crop pollination have stimulated interest in potential effects of novel pesticides on wild bees. Yet pesticide toxicity studies on wild bees remain rare, and few studies have included long-term monitoring of bumble bee colonies or testing of foraging ability after pesticide exposure. Larval bees feeding on exogenous pollen and exposed to pesticides during development may result in lethal or sub-lethal effects during the adult stage. We tested the effects of a naturally derived biopesticide, spinosad, on bumble bee (Bombus impatiens Cresson) colony health, including adult mortality, brood development, weights of emerging bees and foraging efficiency of adults that underwent larval development during exposure to spinosad. We monitored colonies from an early stage, over a 10-week period, and fed spinosad to colonies in pollen at four levels: control, 0.2, 0.8 and 8.0 mg kg,1, during weeks 2 through 5 of the experiment. At concentrations that bees would likely encounter in pollen in the wild (0.2,0.8 mg kg,1) we detected minimal negative effects to bumble bee colonies. Brood and adult mortality was high at 8.0 mg kg,1 spinosad, about twice the level that bees would be exposed to in a ,worst case' field scenario, resulting in colony death two to four weeks after initial pesticide exposure. At more realistic concentrations there were potentially important sub-lethal effects. Adult worker bees exposed to spinosad during larval development at 0.8 mg kg,1 were slower foragers on artificial complex flower arrays than bees from low or no spinosad treated colonies. Inclusion of similar sub-lethal assays to detect effects of pesticides on pollinators would aid in development of environmentally responsible pest management strategies. Copyright © 2005 Society of Chemical Industry [source] Pollination in Jacaranda rugosa (Bignoniaceae): euglossine pollinators, nectar robbers and low fruit setPLANT BIOLOGY, Issue 2 2009P. Milet-Pinheiro Abstract Nectar robbers access floral nectar in illegitimate flower visits without, in general, performing a pollination service. Nevertheless, their effect on fruit set can be indirectly positive if the nectar removal causes an incremental increase in the frequency of legitimate flower visits of effective pollinators, especially in obligate outcrossers. We studied pollination and the effect of nectar robbers on the reproductive fitness of Jacaranda rugosa, an endemic shrub of the National Park of Catimbau, in the Caatinga of Pernambuco, Brazil. Xenogamous J. rugosa flowers continuously produced nectar during the day at a rate of 1 ,l·h,1. Female and male Euglossa melanotricha were the main pollinators. Early morning flower visits substantially contributed to fruit set because stigmas with open lobes were almost absent in the afternoon. Ninety-nine per cent of the flowers showed damage caused by nectar robbers. Artificial addition of sugar water prolonged the duration of flower visits of legitimate flower visitors. Removal of nectar, simulating the impact of nectar robbers, resulted in shorter flower visits of euglossine bees. While flower visits of nectar-robbing carpenter bees (Xylocopa frontalis, X. grisescens, X. ordinaria) produced only a longitudinal slit in the corolla tube in the region of the nectar chamber, worker bees of Trigona spinipes damaged the gynoecium in 92% of the flowers. This explains the outstandingly low fruit set (1.5%) of J. rugosa in the National Park of Catimbau. [source] | ||||||||||