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1.
M. Dittrich 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1995,177(2):207-217
Color induction in the honeybee is investigated in color discrimination experiments. An individual bee walks in a dark arena and is trained to a self-luminant stimulus presented from below. In the dual-choice tests the dark background is replaced by a colored induction stimulus. Choice behavior is recorded by TV camera and analyzed by computer. Successive color induction is separated from simultaneous induction by analysis of the walking paths. Only successive color induction occurs. Simultaneous effects are not observed. That is a stimulus acts as a color inducing stimulus only when the bee crosses this stimulus. Thus, the color perceived by a given eye region is found to be dependent on the viewing history, but not on the stimuli presented simultaneously on neighboring parts of the retina. Color induction in the honeybee described in terms of selective sensitivity decrease (adaptation) does not explain all behavioral effects induced by the stimulus. The time course of successive color induction is calculated from the exposure times to the induction stimulus and from the choice behavior. The data suggest that color induction is complete after a few seconds. Photoreceptor adaptation is sufficient to explain the observed time course. 相似文献
2.
ABSTRACT. Virgin queens are as effective as mated laying queens at inhibiting colonies from rearing queens but not from producing queen cell cups. Colonies without brood produce fewer queen cell cups than similar colonies that have brood. Colonies without queens forage much less and collect less pollen than with either a mated or virgin queen. Colonies with virgin queens forage as much as those with mated queens but collected less pollen. 相似文献
3.
《Saudi Journal of Biological Sciences》2019,26(5):890-896
This study was conducted at the apiary of the Beekeeping Research Section at the Sakha Agricultural Research Station, ARC, Kafrelsheikh, and other apiaries in Kafrelsheikh province, during two successive years 2015 and 2016. The study aimed to survey nectar and pollen floral resources in Kafrelsheikh province. Ninty seven plant species belonging to 33 families were recorded as nectar sources, and 82 plant species belonging to 36 families were recorded as pollen sources during the whole year. The largest amount of monthly trapped pollen was obtained during May followed by August. It can be concluded that, beekeepers in Kafrelsheikh province can harvest good honey yield at the end of blooming seasons of citrus (Citrus spp.) during March and April, Egyptian clover (Trifolium alexandrinum L.) during May and June, loofah (Luffa aegyptiaca Mill.) during June to October, cotton (Gossypium spp.) during July and August, and banana (Musa spp.) during August and September. They also, could be trapping pollen loads collected from faba bean (Vicia faba L.) and flax (Linum usitatissimum L.) during January to March, date palm (Phoenix dactylifera L.) during March and April, Egyptian clover during May and June, summer seed watermelon (Citrullus lanatus var. colothynthoides L.) during June and July, loofah and maize (Zea mays L.) during June to November. 相似文献
4.
《Peptides》2014
Honeybee stings are a severe public health problem. Bee venom contains a series of active components, including enzymes, peptides, and biogenic amines. The local reactions observed after envenoming include a typical inflammatory response and pain. Honeybee venom contains some well-known polycationic peptides, such as Melittin, Apamin, MCD peptide, Cardiopep, and Tertiapin. Secapin in honeybee venom was described 38 years ago, yet almost nothing is known about its action. A novel, variant form of this peptide was isolated from the venom of Africanized honeybees (Apis mellifera). This novel peptide, named Secapin-2, is 25 amino acid residues long. Conformational analyses using circular dichroism and molecular dynamics simulations revealed a secondary structure rich in strands and turns, stabilized by an intramolecular disulfide bridge. Biological assays indicated that Secapin-2 did not induce hemolysis, mast cell degranulation or chemotactic activities. However, Secapin-2 caused potent dose-related hyperalgesic and edematogenic responses in experimental animals. To evaluate the roles of prostanoids and lipid mediators in the hyperalgesia and edema induced by this peptide, Indomethacin and Zileuton were used to inhibit the cyclooxygenase and lipoxygenase pathways, respectively. The results showed that Zileuton partially blocked the hyperalgesia induced by Secapin-2 and decreased the edematogenic response. In contrast, Indomethacin did not interfere with these phenomena. Zafirlukast, a leukotriene receptor antagonist, blocked the Secapin-2 induced hyperalgesia and edematogenic response. These results indicate that Secapin-2 induces inflammation and pain through the lipoxygenase pathway in both phenomena. 相似文献
5.
To date, there are only few reports of immediate early genes (IEGs) available in insects. Aiming at identifying a conserved IEG in insects, we characterized an Egr homolog of the honeybee (AmEgr: Apis mellifera Egr). AmEgr was transiently induced in whole worker brains after seizure induction. In situ hybridization for AmEgr indicated that neural activity of a certain mushroom body (a higher brain center) neuron subtype, which is the same as that we previously identified using another non-coding IEG, termed kakusei, is more enhanced in forager brains. These findings suggest that Egr can be utilized as an IEG in insects. 相似文献
6.
Judith Reinhard Mandyam V. Srinivasan Shaowu Zhang 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2006,192(4):409-416
Foraging honeybees are likely to learn visual and chemical cues associated with many different food sources. Here, we explore
how many such sources can be memorized and recalled. Marked bees were trained to visit two (or three) sugar feeders, each
placed at a different outdoor location and carrying a different scent. We then tested the ability of the bees to recall these
locations and fly to them, when the training scents were blown into the hive, and the scents and food at the feeders were
removed. When trained on two feeder locations, each associated with a different scent, the bees could correctly recall the
location associated with each scent. However, this ability broke down when the number of scents and feeder locations was increased
to three. Performance was partially restored when each of the three training feeders was endowed with an additional cue, namely,
a distinct colour. Our results suggest that bees can recall a maximum of two locations when each is associated with a different
scent. However, this number can be increased if the scent cues are augmented by visual cues. These findings have implications
for the ways in which associations are established and laid down in honeybee memory. 相似文献
7.
Two types of mechanosensitive proprioceptor organ are present on the stinging apparatus of the honeybee: campaniform sensilla and mechanosensory hairplates. The campaniform sensilla are located on the surface of the tapering sting-shaft, which comprises an unpaired stylet and paired lancets. Each sensillum on the lancet differs from that on the stylet in terms of their topography and external morphology. The sensory afferents of the campaniform sensilla display slow-adapted firing responses to deformation of the cuticle that would be caused by the action of inserting the sting into a substrate, and their afferent signals induce and/or prolong the stinging response. By contrast, the mechanosensory hairplates are located at basal cuticular plates and on the posterior surface of the lancet valves. Two fields of hairplates on the second ramus at the ventral edge of the groove and on the antero-lateral edge of the oblong plate respond synchronously to protraction of the lancet. During the stinging response, these hairplates are likely to detect any sliding movement of the lancet and its position relative to the stylet. Afferent signals produced by them are likely to provide important information to the neuronal circuit for the generation and modulation of the stinging motor pattern. 相似文献
8.
In honeybee(Apis mellifera)colonies,queens and workers are alternative forms of the adult female honeybee that develop from genetically identical zygotes but that depend on differential nourishment.Queens and workers display distinct morphologies,anatomies and behavior,better known as caste differentiation.Despite some basic insights,the exact mechanism responsible for this phenomenon,especially at the molecular level,remains unclear although some progress has been achieved.In this study,we examined mRNA levels of the TOR(target of rapamycin)and Dnmt3(DNA methyltransferase 3)genes,closely related to caste differentiation in honeybees.We also investigated mRNA expression of the S6K(similar to RPS6-p70-protein kinase)gene linked closely to organismal growth and development in queen and worker larvae(1-day and 3-day old).Last,we investigated the methylation status of these three genes in corresponding castes.We found no difference in mRNA expression for the three genes between 1st instar queen and worker larvae;however,3rd instar queen larvae had a higher level of TOR mRNA than worker larvae.Methylation levels of all three genes were lower in queen larvae than worker larvae but the differences were not statistically significant.These findings provide basic data for broadening our understanding of caste differentiation in female honeybees. 相似文献
9.
S. W. Zhang M. Lehrer M. V. Srinivasan 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1998,182(6):747-754
This study investigates the honeybee's ability to learn routes based on visual stimuli presented to a single eye, and to
then navigate these routes using the other (naive) eye. Bees were trained to walk through a narrow tunnel carrying visual
stimuli on the two walls. At the end of the tunnel the bees had to choose between two arms, one of which led to a feeder.
In a first experiment, bees had to learn to choose the left arm to get a reward when the right wall carried a yellow grating,
but the right arm when the left wall carried a blue grating. The bees learned this task well, indicating that stimuli encountered
by different eyes could be associated with different routes. In a second experiment, bees had to turn left when the right
eye saw a blue grating, but to the right when the same eye saw a yellow grating. They also learned this task well. In subsequent
tests, they chose the correct arm even when these gratings were presented to the untrained eye. These results suggest that
there is interocular transfer of route-specific learning with respect to visual stimuli that function as navigational “signposts”.
Accepted: 18 December 1997 相似文献
10.
Grabensteiner E Bakonyi T Ritter W Pechhacker H Nowotny N 《Journal of invertebrate pathology》2007,94(3):222-225