Investigation of gut microbial communities associated with indigenous honey bee (Apis mellifera jemenitica) from two different eco-regions of Saudi Arabia

The microbial communities associated with the alimentary tract of honey bees are very important as they help with food digestion, provide essential nutrients, protect the host from pathogens, detoxify harmful molecules, and increase host immunity. In this study, the structural diversity of the gut microbial communities of native honey bees, Apis mellifera jemenitica from two different geographical regions (Riyadh and Al-Baha) of Saudi Arabia was analyzed by culture-dependent methods and 16S ribosomal RNA (rRNA) gene sequencing. In this study, 100 bacterial isolates were cultivated and phylogenetic analyses grouped them into three phyla: Proteobacteria, Firmicutes, and Actinobacteria. Bacteria in the phylum Proteobacteria were the most dominant (17 species), followed by Firmicutes (13 species) and Actinobacteria (4 species). Some of the identified bacteria (Citrobacter sp., Providencia vermicola, Exiguobacterium acetylicum, and Planomicrobium okeanokoites) were reported for the first time in the genus Apis, while others identified bacteria belonged to the genera Proteus, Enterobacter, Bacillus, Morganella, Lactobacillus, and Fructobacillus. To the best of our knowledge, this is the first study on the gut microbiota of the local honey bees in Saudi Arabia.     

蜜蜂花粉采集器官和采集飞行的线性比例分析

本研究从采粉工蜂飞行中能量消耗相关的几个方面入手,分析了蜜蜂属(Apis) 8个物种的花粉采集器官。结果表明,花粉筐表面积、翅膀表面积、体重及胸部动力容量与蜂种个体的体长呈极显著相关,并且它们随蜂种个体的增大而呈对数线性比例增加。除意大利蜜蜂(A·mellifera ligustica)以外,花粉团重量与花粉筐和基跗节表面积成线性比例。工蜂负重前后重量的变化与花粉筐和翅膀的表面积不成比例[动物学报51 (5) :947 -951 , 2005]。     

Eicosanoids act in nodulation reactions to bacterial infections in newly emerged adult honey bees, Apis mellifera, but not in older foragers

Nodulation is the first, and qualitatively predominant, cellular defense reaction to bacterial infections in insects. We tested the hypothesis that eicosanoids also mediate nodulation reactions to bacterial challenge in adults of a social insect, the honey bee, Apis mellifera. Treating newly-emerged experimental bees with the eicosanoid biosynthesis inhibitor, dexamethasone, impaired nodulation reactions to bacterial infections, and the influence of dexamethasone was reversed by treating infected insects with arachidonic acid, an eicosanoid precursor. Several other eicosanoid biosynthesis inhibitors, including the cyclooxygenase inhibitor, indomethacin, and the dual cyclooxygenase/lipoxygenase inhibitor, phenidone, also impaired the ability of experimental honeybees to form nodules in reaction to bacterial challenge. The influence of phenidone on nodulation was expressed in a dose-dependent manner. However, in experiments with older honey bees foragers, similar bacterial challenge did not evoke nodulation reactions. We infer from our results that while eicosanoids mediate cellular immune responses to bacterial infections in newly emerged honey bees, and more broadly, in most insect species, nodulation reactions to bacterial challenge probably do not occur in all phases of insect life cycles.     

How long will honey bees (<Emphasis Type="Italic">Apis mellifera</Emphasis> L.) be stimulated by scent to revisit past-profitable forage sites?

Honey bees utilise floral food sources that vary temporally in their relative and absolute quality. Via a sophisticated colony organisation, a honey bee colony allocates its foragers such that the colony focuses on the most profitable forage sites while keeping track of changes within its foraging environment. One important mechanism of the allocation of foragers is the ability of experienced foragers to revisit past-profitable forage sites after a period of temporary dearth caused by, for example, inclement weather. The scent of past-profitable forage within the colony brought back by other foragers is sufficient to reactivate these experienced foragers. Here I determine for how long bees react to the scent of a past-profitable forage site. I show that the ability of foragers to revisit the location of a past-profitable food source diminishes rapidly over a period of 10 days, until no forager reacts to the cue (scent). I discuss the implications of these findings with respect to the colony’s ability to react rapidly to changing foraging conditions.     

以色列急性麻痹病毒(IAPV)的特性及入侵受体的研究进展

以色列急性麻痹病毒（Israeli acute paralysis virus, IAPV）是一种严重危害蜜蜂健康的病毒,其感染特性主要表现为较强的传染性和致病性。IAPV能感染多种宿主,不仅能感染蜜蜂,还能感染熊蜂、无刺蜂、胡蜂和蚂蚁等昆虫以及狄斯瓦螨Varroa destructor。受体是决定其宿主范围和嗜性组织的重要因素,病毒入侵过程中关键的一步就是与受体蛋白结合,但迄今为止,国内外针对蜜蜂病毒的受体研究较为匮乏,尚无该病毒受体报道。NPC（NPC intracellular cholesterol transporter）,一种细胞内转运胆固醇的蛋白,是多种昆虫病毒的胞内受体,在病毒感染中扮演着关键的角色。之前研究表明,该蛋白可能与蜜蜂病毒的感染过程有关。本文综述了IAPV的特性和可能的入侵受体,包括病毒分子结构特征、流行与传播、宿主范围以及感染机制,以期深入认识IAPV的发病机制。     

Economics of technical efficiency in white honey production: Using stochastic frontier production function

This study estimates and compares technical efficiency levels among beekeeping projects with various production capacities using a sample drawn from Fayoum Governorate in Egypt. The study also compares among beekeeping’s most important economic indicators, estimates the optimum production amount, and investigates why technical efficiency in Egyptian beekeeping is declining. We conclude that the average cost to produce one ton of honey decreases when production capacity increases. Furthermore, the average total, net return, and return on investment of one Egyptian pound increases when production capacity increases. Moreover, the results of a stochastic frontier production function indicate an increased return to scale. Finally, the results of maximum likelihood estimation show that technical inefficiency helps explain the deviation of actual from optimal production amounts.     

Acquisition of a time-memory in forager honey bees

Forager honey bees can associate the time of day with the presence of food at locations outside the hive. It is thought that this time-memory enables the bee to make a spatio-temporal match between its behavior and floral nectar secretion rhythms. Despite a long tradition of research, the mechanisms by which the time-memory becomes established are unknown. We investigated the influences of two experiential factors on the acquisition of time-memory: (1) the number of collecting visits made by the forager within a feeding bout during a restricted time of day and (2) the number of days of exposure to the restricted feeding time. Our results indicate that these two factors control different processes. The number of days of experience influences the temporal accuracy of reconnaissance behavior to the food source. The cumulative number of collecting visits within the feeding bouts has no apparent effect on time-accuracy but, instead, determines the probability of exhibiting food-anticipatory behavior and, if that overt behavior is performed, the intensity of its expression. This paper is dedicated to the memory of Prof. James L. Larimer.     

On a simplified model for pattern formation in honey bee colonies

We present a simplified version of a previously presented model (Camazine et al. (1990)) that generates the characteristic pattern of honey, pollen and brood which develops on combs in honey bee colonies. We demonstrate that the formation of a band of pollen surrounding the brood area is dependent on the assumed form of the honey and pollen removal terms, and that a significant pollen band arises as the parameter controlling the rate of pollen input passes through a bifurcation value. The persistence of the pollen band after a temporary increase in pollen input can be predicted from the model. We also determine conditions on the parameters which ensure the accumulation of honey in the periphery and demonstrate that, although there is an important qualitative difference between the simplified and complete models, an analysis of the simplified version helps us understand many biological aspects of the more complex complete model. Corresponding author     

后基因组时代的蜜蜂QTL研究

继果蝇、按蚊和家蚕之后,意大利蜜蜂Apis mellifera（膜翅目： 蜜蜂科）成为又一种被完整测得基因组序列的昆虫。从此,蜜蜂研究进入后基因组时代。作为一种典型的社会性昆虫,许多和蜜蜂社会生活紧密相关的性状都是数量性状。这些性状研究中广泛涉及到了数量性状位点（quantitative traits loci,QTL）定位研究。本文综述了应用QTL对蜜蜂取食行为、自卫行为、体长、逆转学习等的研究现状,同时结合国内外最新研究进展,总结并展望了后基因组时代蜜蜂QTL的研究方向。     

蜜蜂microRNA的研究进展

MicroRNA (miRNA)是一类长度为18~24 nt的内源性非编码小RNA分子,它能通过与靶标mRNA 分子互补结合抑制蛋白质翻译或导致 mRNA 降解,从而调控靶基因表达。蜜蜂是重要的社会性经济昆虫,一直是国际上热门的研究对象。迄今为止,通过各种生物技术在蜜蜂中发现已鉴定注册的miRNA共有218个,对蜜蜂miRNA的研究表明其在蜜蜂的胚胎发育、级型分化、劳动分工和免疫防御等方面可能具有重要的调控作用。本文就miRNA对蜜蜂蜂王和工蜂级型分化、哺育蜂和采集蜂劳动分工、舞蹈行为、脑部神经功能及免疫防御等方面调控作用的最新研究进展进行了综述,以期为进一步研究miRNA提供借鉴和参考。     

Increase in dance imprecision with decreasing foraging distance in the honey bee <Emphasis Type=Italic>Apis mellifera</Emphasis> L. is partly explained by physical constraints

Honey bee foragers communicate the direction and distance of both food sources and new nest sites to nest mates by means of a symbolic dance language. Interestingly, the precision by which dancers transfer directional information is negatively correlated with the distance to the advertised food source. The ‘tuned-error’ hypothesis suggests that colonies benefit from this imprecision as it spreads recruits out over a patch of constant size irrespective of the distance to the advertised site. An alternative to the tuned-error hypothesis is that dancers are physically incapable of dancing with great precision for nearby sources. Here we revisit the tuned-error hypothesis by studying the change in dance precision with increasing foraging distance over relatively short distances while controlling for environmental influences. We show that bees indeed increase their dance precision with the increase in foraging distance. However, we also show that dances performed by swarm-scouts for a nearby (30 m) nest site, where there could be no benefit to imprecision, are either without or with only limited directional information. This result suggests that imprecision in dance communication is caused primarily by physical constraints in the ability of dancers to turn around quickly enough when the advertised site is nearby.