Honey bees are affected by a variety of factors, so they have to be thoroughly managed according to their lifestyle. The activity of the honey bee foragers represent an important parameter of the hive state. Here, the real-time and automatic monitoring system using dual infrared sensors was applied for counting the foraging activity of honey bees based on ICT. According to this study, this system is very accurate with a relative error of 3.98% / 4.43% compared to manual counting through video analysis. This system showed the scalability of the system through the internal and external temperature sensors connected through the main board and BLE module. Furthermore, the data measured through this system for one month were analyzed, the monthly average foraging activity and the number of lost foragers were measured (1.88% of outgoing bees), and at the same time, the foraging patterns according to the changes of temperature and time were analyzed. This study suggests that the development of apicultural, scientific and educational materials with more powerful real-time monitoring tools through expansion of a complex monitoring system and big data accumulation.

Sacbrood virus (SBV) caused significant colony collapse in Korean Apis cerana. Considering that hygienic behavior in honey bees confers colony-level resistance against brood diseases, we utilized this trait for selecting A. cerana colonies. In addition, the brood survival rate was evaluated after colonies were SBV-inoculated. Over four selective generations, dead brood removal and brood survivorship in selected colonies were higher than those in the unselected colonies (P < 0.01, 99.3 vs. 89.9% for removal of pin-killed pupae; P < 0.01, 99.0 vs. 63.9% for removal of SBV-killed larvae; and P < 0.01, 70.0 vs. 9.2% for brood survivorship). Following SBV-inoculation, selected colonies showed an increase in the number of surviving pupae and adults, whereas unselected colonies collapsed mostly. Our results confirm the feasibility of selecting SBV-resistant A. cerana.

농촌진흥청 개발 품종인 토종벌 신품종(질병저항성 우수계통)에 대해 전남지역에서의 형질특성(봉세발달, 마리당 수밀력, 청소력 등)을 조사하였다. 질병저항성 계통(RS)으로 육성된 토종벌의 유밀기 마리당 수밀력은 들어오는 일벌의 무게가 80.89±8.95mg, 나가는 일벌의 무게가 63.56±8.90mg으로 조사되었고, 비저항성계통(NRS)은 각각 83.22±1.39, 66.67±1.20mg으로 조사되어 RS에서 그 무게차가 0.7mg 더 높았으나 통계적 유의차는 없었다. Pin killed test에 의한 사충제거능력(청소력)은 제거하지 못한 유충잔존율이 RS에서 12시간과 24시간 경과시 14.00±10.39와 7.00±3.46으로, NRS에서는 20.33±14.29, 13.33±10.41%로 조사되었으며, 특히 RS와 NRS의 사충 비제거율이 24시간 경과하였을 때 4.67±2.08, 8.33±7.77%로 RS가 우수한 특성을 보였다. 신규여왕벌 입식 후 봉군세력발달은 NRS에 비하여 RS의 일벌수, 번데기 및 유충수의 발달율이 안정적이고 다소 빠르게 증가하였다.

Honey bee, Apis mellifera L., have been widely used as a model organism for biological science because of its highly developed sociality, specialized labor division and passive population management. In order to examine the expression patterns of genes putatively involved in social development in honey bee, quantitative real-time PCR (qRT-PCR) that has been widely used to investigate the expression level of target gene can be used in honey bee study. However, the selection and validation of optimal reference genes is a crucial step prior to running qRT-PCR. In the present study, therefore, the seasonal expression stability of five candidate reference genes in the abdomen of forager and nurse was investigated using three programs (geNorm, NormFinder and BestKeeper), and selected reference genes were validated by the normalization of expression level of vg encoding vitellogenin. Although three programs revealed slightly different gene stability values, overall the combination of two genes (rpS18 and gapdh encoding ribosomal protein S18 and glyceraldehyde-3-phosphate dehydrogenase, respectively) was resulted in the most suitable use for normalization of the target gene in forager. However, a single gene, either rpL32 or rpS18 in the nurse or either rpL32, rpS18, or gapdh in the comparison between foragers and nurses, were suggested to be applied for normalization of seasonal and labor-specific gene expression by qRT-PCR.

Lately, CRISPR-Cas9 has become one of the most essential tools to understand gene’s function. In the honeybee, however, the application of CRISPR technology has been hindered by various factors leading to very few reports of success in genome editing. Among these, collection of honeybee embryos for microinjection has been a time-consuming procedure, mainly limiting the applicability of the genome editing technique to honeybees. To improve the drawbacks of the conventional plastic plug-based system, we have developed a film-assisted honeybee embryo collection system (FECS) using transparent film as a detachable bottom layer. In this new system, eggs are laid on the detachable film surface and collected in a batch, and thus no additional alignment is required for microinjectoin. As the film can be easily replaced with in a few seconds, embryo collection can be repeated continuously after a single caging of a queen. Also, unlike conventional plug-based systems, the new system utilizes 100% of the eggs laid by the queen, thereby increases the yield three times in theory. The main unit of the system can be printed with ordinary SLA/DLP type 3D printer and the stl file for 3D printing will be distributed online.

The honey bee soluble acetylcholinesterase 1 (AmAChE1) is overexpressed under the overwintering and brood rearing-suppressed conditions. To investigate the role of AmAChE1 in regulating acetylcholine (ACh) titer, ACh concentrations both in the head (neuronal) and abdomen (non-neuronal) were analyzed. ACh titer was significantly lower in both tissues of worker bees under the overwintering and brood rearing-suppressed conditions compared to control bees. The expression levels of another two factors that regulate ACh titer, choline acetyltransferase (AmAChT) and acetylcholinesterase 2 (AmAChE2), were not altered as judged by qPCR and native PAGE, suggesting that the lower ACh titer was mainly regulated by AmAChE1. For precise verification of AmAChE1 as an ACh titer regulator, honey bees were put under brood rearing-suppressed condition to induce AmAChE1 and injected AmAChE1 dsRNA to knock down the gene. The ACh titer of AmAChE1-knocked down honey bees was 1.9 and 2.6 folds higher than that of control bees in head and abdomen, respectively. Taken together, in spite of its extremely low catalytic activity, the overexpression of AmAChE1 is likely to be related with the low level of ACh homeostasis, perhaps via ACh sequestration, under brood rearingsuppressed condition, and likely induce metabolic changes through ACh receptors-related pathways.

미포장충류(Nosema spp. (NS))는 양봉꿀벌에 심각한 문제를 야기시키는 기생충으로 효과적인 방제물질의 선발이 무엇보다 중요하다. 본 연구는 노제마병과 기타 꿀벌의 발생유행시기의 구명과 더불어 3가지 노제마병 방제물질(M1 = 벌꿀희석의 레몬쥬스; M2 = 설탕시럽 혼합의 카모마일 추출물; M3 = 설탕시럽 혼합의 항생물질 스트리베트)을 평가하고자 수행하였다. 꿀벌 성충과 유충집단의 질병 유행시기를 년간 조사하였으며, 야외 및 실험실 조건에서 노제마병에 대한 M1, M2, M3의 효과를 평가하였다. 조사결과 극소수의 꿀벌 성충과 유충 질병이 발견되었다. 노제마 병은 겨울과 봄 기간 저온과 고습조건에서 검출되었다. 포장실험에서 M2는 36.66%까지 발병억제 능력을 보였으며, 반면M3는 23.33%, M1는 13.33%의 억제효과를 보였다. 실내실험에서 M2가 방제효과가 가장 좋았고, 그 다음 M1와 M3 이었다. 3가지 방제물질은 병에 감염된 꿀벌성충의 생존력을 크게 높이는 것으로 나타났다. 본 연구는 노제마병 방제를 위한 천연물질로 카모마일의 잠재적 방제효과를 제시하고 있다.

Chitosan is attracting attention as a health supplement material because of its various physiological activities. In this study, sugar solution containing chitosan was fed to honey bees to induce the production of ‘chitosan fortified honey’ by their same mode of natural honey production. To accomplish this, sugar solutions containing 0.1%, 1%, 2% and 5% chitosan were fed to the honey bees. Fully inverted Chitosan-honey was harvested after feeding the chitosan in sugar solution. To investigate the anti-obesity and immune-enhancing effects of Chitosan-honey, 1% and 10% Chitosan-honey containing drinking water were administrated freely to C57BL mice. Glucosamine concentrations in serum rapidly increased to peak levels in 10 minutes (1261.0 ± 97.6 ng/ml), then decreased gradually for more than 24 hours 793.0 ± 34.7 ng/ml. There were no significant differences in weight and or splenocyte proliferative capacity among experimental mice groups. However, increased granulocytes and monocytes were observed upon flow cytometric analysis. These results suggest that Chitosan-honey could induce removal of foreign antigens. In conclusion, ‘Chitosan-honey’ developed in this study has the potential for use as a honey type dietary health supplement with the same bioactivity as chitosan; however additional research should be conducted to confirm these effects.

The honey bee, Apis mellifera ligustica (Hymenoptera: Apidae), strain with a high hygienic behavior (HHB) has been bred for several years in Korea, and a diagnosis system to distinguish it from low hygienic behavior (LHB) strain has been necessitated. Thus, complete mitogenome of the two strains were sequenced through Next-Generation Sequencing technique to detect SNPs. Comparison of the mitogenome sequences from the two strains of A. m. ligustica have detected 23 SNPs in 11 PCGs and these were further confirmed the presence of SNPs using each 10 individuals selected randomly from each strain, indicating that these SNP markers might be useful to diagnose the honeybee strains with the HHB. Therefore, mitogenome sequences are promising genome source to detect SNP markers, particularly for inbred female iso-lines.

Honey bee has been widely used as a model insect for biological sciences because of its sociality and specialized labor division. For the investigation of the seasonal and labor-dependent expression patterns of genes putatively involved in its sociality, quantitative real-time PCR (qRT-PCR) can be applied to quantify gene expression level and selection of reliable reference gene(s) for normalization is an accurate step. In this study, using three softwares (geNorm, NormFinder and BestKeeper), we evaluated seasonal expression stabilities of four reference genes that have been widely used for qRT-PCR in forager and nurse heads. Among four candidates, two genes, rpS18 and gapdh, were suggested to be the optimal reference genes for qRT-PCR.

Honey bees are challenged with declining colony numbers, generally called ‘Colony Collapse Syndrome’ (CCS). This issue is certainly a syndrome because it is due to a range of threats, including parasitic mites, exposure to agricultural chemicals and various viruses, among other things. We posed the hypothesis the CCS could also be due to declining nutritional qualities, which may relate to digestive physiology. Because there is no information on honey bee lipid nutrition and digestion, we characterized a digestive phospholipase A2 in honey bee midguts. In this paper, I will report on some of our findings. With a focus on students, I will also use this report to share thoughts on presenting and writing for international audiences.