Reproductive Potential Accelerates Preimaginal Development of Rebel Workers in Apis mellifera

Rebel workers develop from eggs laid by the previous queen, before it went swarming and left the colony orphaned, until the emergence of a new queen. In contrast to normal workers developing in the queen’s presence, rebels are set to reproduce and avoid rearing of successive bee generations. They have more ovarioles in their ovaries, as well as more developed mandibular glands and underdeveloped hypopharyngeal glands, just like the queen. We posited that rebels are not only similar to queens in some anatomical features, but also develop in a shorter time in comparison to normal workers. Therefore, the aim of this study was to compare preimaginal development duration in rebel and normal workers. The results show that rebels, i.e., workers with a higher reproductive potential, had a significantly shorter preimaginal development period (mean ± SD, 19.24 ± 0.07 days) than normal workers (22.29 ± 0.32 days). Our result confirmed that workers who develop in a queen-less colony undergo a shorter preimaginal development than those in a queen-right colony.

Evaluation of Enzymatic Activity in the Transformation of Nectar into Honey in Indigenous Rockbee, Apis dorsata F.

Enzymes form integral part and play decisive role in biological Systems and metabolic network. The present studies delve on the role of enzymes viz., invertase, amylase, glucose oxidase and catalase in nectar-honey transformation during May 2019 to April 2020. Data on enzymatic activity in all the five stages related to honey formation from nectar i.e., floral nectar (fn), honey crop of foragers (hf), honey crop of house bees (hh), unsealed honey cells (uh) and sealed honey cells (sh) was evaluated. Invertase in fn and sh cells was found minimum of 0.00 ml and maximum of 42.40 ml, respectively. Similarly, amylase in the fn was least (0.00 ml) and highest in sh (16.01 ml) and catalase was observed to be 0.001 ml in floral nector and highest in sealed honey cells i.e., 16.01 ml and 4.96 ml,respectively. Accordingly, glucose oxidase in fn and sh cells was minimum of 0.00 ml and maximum of 6.68 ml respectively. Correspondingly, catalase in the fn was least (0.00 ml) and highest in sh (4.96 ml). The analysis of variance of invertase and amylase was significant at 1 % level (p<0.01), whereas glucose oxidase and catalase Were statistically non-significant at 1 % level (p<0.01). Results have confirmed that the sources of all enzymes are instigated from hypopharyngeal, post-cerebral, thoracic, labial and mandibular glands of foragers and house bees which are accountable for honey formation. Further, each enzyme is substrates specific which are discussed in ensuing paper.

New Insights into the Biological and Pharmaceutical Properties of Royal Jelly

Royal jelly (RJ) is a yellowish-white and acidic secretion of hypopharyngeal and mandibular glands of nurse bees used to feed young worker larvae during the first three days and the entire life of queen bees. RJ is one of the most appreciated and valued natural product which has been mainly used in traditional medicines, health foods, and cosmetics for a long time in different parts of the world. It is also the most studied bee product, aimed at unravelling its bioactivities, such as antimicrobial, antioxidant, anti-aging, immunomodulatory, and general tonic action against laboratory animals, microbial organisms, farm animals, and clinical trials. It is commonly used to supplement various diseases, including cancer, diabetes, cardiovascular, and Alzheimer’s disease. Here, we highlight the recent research advances on the main bioactive compounds of RJ, such as proteins, peptides, fatty acids, and phenolics, for a comprehensive understanding of the biochemistry, biological, and pharmaceutical responses to human health promotion and life benefits. This is potentially important to gain novel insight into the biological and pharmaceutical properties of RJ.

Honeybees possess a structurally diverse and functionally redundant set of queen pheromones

Queen pheromones, which signal the presence of a fertile queen and induce workers to remain sterile, play a key role in regulating reproductive division of labour in insect societies. In the honeybee, volatiles produced by the queen's mandibular glands have been argued to act as the primary sterility-inducing pheromones. This contrasts with evidence from other groups of social insects, where specific queen-characteristic hydrocarbons present on the cuticle act as conserved queen signals. This led us to hypothesize that honeybee queens might also employ cuticular pheromones to stop workers from reproducing. Here, we support this hypothesis with the results of bioassays with synthetic blends of queen-characteristic alkenes, esters and carboxylic acids. We show that all these compound classes suppress worker ovary development, and that one of the blends of esters that we used was as effective as the queen mandibular pheromone (QMP) mix. Furthermore, we demonstrate that the two main QMP compounds 9-ODA and 9-HDA tested individually were as effective as the blend of all four major QMP compounds, suggesting considerable signal redundancy. Possible adaptive reasons for the observed complexity of the honeybee queen signal mix are discussed.