Honeybees foraging response in genetically diversified opium poppy

Studies were carried out on honeybees foraging on plant flowers. Results showed significantly higher foraging response of honeybees (Apis mellifera) in genetically divergent narcotic plant opium poppy (Papaver somniferum). Of the 18 mutants and two locally adapted cultivars of diverse genotypes screened, eight revealed significantly greater foraging response manifesting honeybee's preference towards specific plant morphotypes. The number of flower bloom did not correspond to number of foraging bees in both mutant and cultivar plant types of opium poppy. The genotype specific foraging response of honeybees could be attributed to physico-chemical properties of opium poppy flowers. This could have implications for the development of opium alkaloid fortified honeys for novel pharmaceuticals and isolation of natural spray compounds to attract honeybee pollinators for promoting crossing and sustainable hybridity in crops.     

Honeybees and bumblebees share similar bacterial symbionts

Associations with symbiotic microorganisms are a major source for evolutionary innovation in eukaryotes. Arthropods have long served as model systems to study such associations, especially since Paul Buchner’s (1965) seminal work that beautifully illustrated the enormous diversity of microorganisms associated with insects. Particularly high taxonomic and functional diversities of microbial symbionts have been found in the guts and gut‐associated organs of insects. These microorganisms play important roles in the digestion, nutrition and defence of the host. However, most studies of gut microorganisms have focused on single host taxa, limiting the ability to draw general conclusions on composition and functional roles of the insect gut microbiota. This is especially true for the diverse and important insect order Hymenoptera that comprises the bees, wasps and ants. Recently, Russell et al. (2009) analysed the bacterial community associated with diverse ant species and found evidence for changes in the microbial gut community coinciding with the evolution of herbivory. In this issue of Molecular Ecology, Martinson et al. (2011) provide the first broad‐scale bacterial survey for bees. Their findings substantiate earlier evidence for a surprisingly simple gut microbiota in honeybees (Apis mellifera) that is composed of only six to ten major phylotypes. Importantly, Martinson et al. demonstrate for the first time that the same bacterial phylotypes are major constituents of other Apis as well as Bombus species, but not of any other bees and wasps outside of the corbiculate bees, a clade of four tribes within the subfamily Apinae. These results indicate that corbiculate bees harbour a specific and possibly co‐evolved bacterial community in their digestive tract. Furthermore, the comparison with other bees and wasps suggests that changes in social lifestyle may have had a stronger effect on the evolution of the gut microbiota than the dietary shift from predatory ancestors to pollen‐feeding (i.e. herbivorous) species. These findings have far‐reaching implications for research on the microbial symbionts of insects as well as on the nutritional physiology of the ecologically and economically important group of corbiculate bees.     

Honeybees are poor pollinators — why?

Contrary to most other bee species honeybees are highly eusocial and hold extremely long-lived societies. Their all-season activities force them to use whatever plants available and prevent any specific adaptations — in the flowers, in honeybees, and in all competing bees. This flexible behaviour in flowers has been a precondition for perennial colony life. But as bees evade becoming contaminated by pollen their visits often do not result in pollination. Honeybee monocultures thus must be avoided by all means.     

Transcriptome differences in the hypopharyngeal gland between Western Honeybees (Apis mellifera) and Eastern Honeybees (Apis cerana)

Background

Apis mellifera and Apis cerana are two sibling species of Apidae. Apis cerana is adept at collecting sporadic nectar in mountain and forest region and exhibits stiffer hardiness and acarid resistance as a result of natural selection, whereas Apis mellifera has the advantage of producing royal jelly. To identify differentially expressed genes (DEGs) that affect the development of hypopharyngeal gland (HG) and/or the secretion of royal jelly between these two honeybee species, we performed a digital gene expression (DGE) analysis of the HGs of these two species at three developmental stages (newly emerged worker, nurse and forager).

Results

Twelve DGE-tag libraries were constructed and sequenced using the total RNA extracted from the HGs of newly emerged workers, nurses, and foragers of Apis mellifera and Apis cerana. Finally, a total of 1482 genes in Apis mellifera and 1313 in Apis cerana were found to exhibit an expression difference among the three developmental stages. A total of 1417 DEGs were identified between these two species. Of these, 623, 1072, and 462 genes showed an expression difference at the newly emerged worker, nurse, and forager stages, respectively. The nurse stage exhibited the highest number of DEGs between these two species and most of these were found to be up-regulated in Apis mellifera. These results suggest that the higher yield of royal jelly in Apis mellifera may be due to the higher expression level of these DEGs.

Conclusions

In this study, we investigated the DEGs between the HGs of two sibling honeybee species (Apis mellifera and Apis cerana). Our results indicated that the gene expression difference was associated with the difference in the royal jelly yield between these two species. These results provide an important clue for clarifying the mechanisms underlying hypopharyngeal gland development and the production of royal jelly.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-744) contains supplementary material, which is available to authorized users.     

Chemical Nature of Phagostimulants in Pollen Attractive to Honeybees

Honey bees display a powerful ability to recognize pollen from most plants as food and non-pollen materials as not being food. We sequentially extracted a mixed species blend of pollen with a range of non polar to polar solvents and tested the extracts for attractiveness and feeding enhancement by young bees. Both non polar and polar materials were independently attractive when added in trace quantities to a plain artificial diet. The attractants have little inherent nutritional value, as addition of phagostimulants to artificial diets did not increase the life spans of bees compared to phagostimulant-free diets. These data indicate that pollen phagostimulants consist not of a single or a few specific compounds, but rather are a suite of diverse components that additively or synergistically serve to exceed a threshold level of stimulation necessary for feeding.     

黄猄蚁对大蜜蜂的捕食行为及其潜在影响

捕食作用会对访花昆虫的种群、行为以及植物适合度产生影响,是植物与传粉者相互关系研究中常被忽视的因素.本文报道了黄猄蚁对大蜜蜂的捕食行为,并模拟捕食的关键环节研究了捕食过程对重要访花昆虫行为的影响.结果表明,黄猄蚁能够利用局部环境主动攻击猎物,利用群体合作捕获采集过程中的体型较大的大蜜蜂,捕食威胁是其影响植物-访花者关系的重要机制.大蜜蜂具有感知花上危险的能力,模拟处理的个体会逃离危险的花或植株并在花上留下标记,将危险信息传递给其它个体.其它拜访者对具有危险信号花的采集频次明显减少,采集时间缩短;模拟处理的影响会随时间推移而较快地消失.此外,该实验没有发现大蜜蜂在花上停留采集过程中具有明显的防御行为.     

Isolation of Chitin and Chitosan from Honeybees

A procedure of isolation of chitin, chitosan, and water-soluble low-molecular-weight chitosan from the corpses of bees has been developed. This procedure includes deproteinization of bee corpses, discoloration of the chitin–melanin complex, deacetylation, and enzymatic hydrolysis of chitosan.     

Thermal Behaviour of Honeybees During Aggressive Interactions

We report here on the interrelationship of aggressive behaviour and thermoregulation in honeybees. Body temperature measurements were carried out without behavioural disturbance by infrared thermography. Guard bees, foragers, drones, and queens involved in aggressive interactions were always endothermic, i.e. had their flight muscles activated. Guards made differential use of their endothermic capacity. Mean thorax temperature was 34.2–35.1°C during examination of bees but higher during fights with wasps (37°C) or attack of humans (38.6°C). They usually cooled down when examining bees whereas examinees often heated up during prolonged interceptions (maximum >47°C). Guards neither adjusted their thorax temperature (and thus flight muscle function and agility) to that of examined workers, nor to that of drones, which were 2–7°C warmer. Guards examined cool bees (<33°C) longer than warmer ones, supporting the hypothesis that heating of examinees facilitates odour identification by guards, probably because of vapour pressure increase of semiochemicals with temperature. Guards in the core of aggressive balls clinged to the attacked insects to fix them and kill them by heat (maximum 46.5°C). Bees in the outer cluster layers resembled normal guards behaviourally and thermally. They served as active core insulators by heating up to 43.9°C. While balled wasps were cooler (maximum 42.5°C) than clinging guards balled bees behaved like examinees with maximum temperatures of 46.6°C, which further supports the hypothesis that the examinees heat up to facilitate odour identification.     

Honeybees can discriminate between Monet and Picasso paintings

Honeybees (Apis mellifera) have remarkable visual learning and discrimination abilities that extend beyond learning simple colours, shapes or patterns. They can discriminate landscape scenes, types of flowers, and even human faces. This suggests that in spite of their small brain, honeybees have a highly developed capacity for processing complex visual information, comparable in many respects to vertebrates. Here, we investigated whether this capacity extends to complex images that humans distinguish on the basis of artistic style: Impressionist paintings by Monet and Cubist paintings by Picasso. We show that honeybees learned to simultaneously discriminate between five different Monet and Picasso paintings, and that they do not rely on luminance, colour, or spatial frequency information for discrimination. When presented with novel paintings of the same style, the bees even demonstrated some ability to generalize. This suggests that honeybees are able to discriminate Monet paintings from Picasso ones by extracting and learning the characteristic visual information inherent in each painting style. Our study further suggests that discrimination of artistic styles is not a higher cognitive function that is unique to humans, but simply due to the capacity of animals—from insects to humans—to extract and categorize the visual characteristics of complex images.