Honeybees (Apis mellifera) are defend on feeds for their larvae and adult bees` healthy life. The nectar is carbohydrate source for making energy. We are extract several sugars from plants for using carbohydrate source to bee. 3 sugar source was extracted from plants (watermelon, cabbage, and mandarin). Almost sample showed high level of insecticidal rate and low level feed intake rate. We were selected 2 type of cabbage sugar syrup that low level insecticidal rate and high level feed intake rate (No 6 cabbage(+fructose) was mixed with 10% fructose and No. 7 cabbage(+pollen) was made with 10 % pollen). Cabbage sugar solution has much more impurities than purified sugar. So, No.6 and No 7 sample can do up-regulation of antimicrobial genes (apideacin, defencin, abacin, and hymenopteacin). Cabbage sugar solution has much more impurities than purified sugar. Our results suggest that up-regulation of antimicrobial genes might be involved in worker through carbohydrate impurities related immune pathways.

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.

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 in both the head (central nervous system) and abdomen (peripheral nervous system) 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. Interestingly, the expression levels of choline acetyltransferase (AmChAT) and molecular marker genes of immune systems were significantly reduced in honey bee head under the same conditions. Taken together, ACh titer appears to be reduced via a cooperative interaction of the AmAChE1 overexpression and AmChAT underexpression and to be linked to reduced inmmune responses under the overwintering and brood rearing-suppressed conditions. The roles of AmAChE1 (with little catalytic activity) and AmChAT in the ACh homeostasis and signaling was discussed in the contexts of immune response and longevity regulation in honey bees.

Among two different acetylcholinesterase (AmAChE1 and AmAChE2) of the western honey bee, the soluble AmAChE1might be related with a stress response as judged from its over-expression in honey bee workers when brood rearingwas suppressed. In this study, to ensure the nature of AmAChE1 responding to stress factors, the expression patternsof AmAChE1 were investigated following various treatments, including varroa mite infestation, bacterial challenge, broodrearing suppression, thermal stresses, chemical treatments, ultraviolet B irradiation, starvation, water restriction and crowdingstress. In addition, transcription profiles of four heat shock protein genes known as general stress markers and vitellogeningene, which is induced in several stress conditions, were tested as positive references. In every tested condition, onlybrood rearing suppression and heat shock were related with the expression of AmAChE1.

서양종 꿀벌의 일벌의 독을 채취하여 정제한 정제봉독에 대한 세균에서의 돌연변이 유발성 검색을 위하여 S. typhimurium의 히스티딘 요구성 균주 TA100, TA1535, TA98, 그리고 TA1537의 균주와 대장균 E. coli의 트립토 판 요구성 균주인 WP2 uvrA를 이용해 복귀돌연변이시험 을 실시하였다. 정제봉독은 부형제로 사용한 멸균생리식 염수에 용해되었으며 모든 농도군의 조제물에서 침전은 관찰되지 않았으며, 정제봉독 조제물을 top agar와 혼합할 때 모든 농도군에서 혼탁이나 침전이 관찰되지 않았다. 대사활성계 적용 TA100, TA1535, TA98 균주에 대해 0, 1.5, 5, 15, 50, 150 및 500 μg/plate의 범위를 설정하고 미 적용시엔 0, 0.15, 0.5, 1.5, 5, 15 및 50 μg/plate의 범위로 설 정하였다. TA1537과 WP2 uvrA균주에 대한 농도 범위은 대사활성계 적용시엔 0, 5, 15, 50, 150, 500 및 1,500를 미 적용시엔 0, 1.5, 5, 15, 50, 150 및 500 μg/plate 범위로 설정하여 시험을 수행하였다. 그 결과 모든 시험균주에서 대사활성계 적용 여부에 상관없이 정제봉독 처리군 의 평균 집락 수는 증가를 나타내지 않았으며, 양성판정 기준을 만족시키지 못하였다. 따라서, 정제봉독은 본 시험 조건 하에 사용한 시험 균주에 복귀돌연변이를 유발하지 않는 것으로 사료되었다.

We developed single nucleotide polymorphism (SNP) markers and are establishing diagnostic systems to distinguish disease resistance- and susceptible-strains of honey bees using the SNPs. For development of SNP markers, whole genome was sequenced each from 20 individuals of “disease resistance-strain” and “susceptible-strain” of Apis mellifera ligustica using the Illumina HiSeq 2000 sequencer. Approximately, 344 and 294 million sequence reads were mapped to the honeybee reference assembly (Amel_4.5) for each strain, respectively. Among the total 2,246,428 SNPs yielded, 33 were found to be fixed between the two strains with all homozygosity. Sixteen of them were casually amplified and sequenced from randomly selected each 10 individual of honey bees from each strain and presented strain specific SNPs. These ten SNPs were used to diagnose the two strains either by original size difference, caused by indel-accompanying SNP, typical PCR-RFLP, or AS PCR.

Honey bee swarming is a natural phenomenon that occurs by changes of colony (i.e. population size and queen condition) and environment conditions. As cuticular hydrocarbons (CHCs) are known to be involved in the communication between honey bee nest-mates, we investigated and compared the CHC profiles of worker bees from individual colonies of 9-days before swarming (PPSC), a day before swarming (PSC), swarming (SG) and remaining (non-swarming) (RG). A total of 53 CHCs were identified by GC-MS, among which 11 compounds showed significantly differential expression patterns between swarming states. Before swarming (between PPSC and PSC), detection levels of 4 CHCs were significantly different, suggesting that production of some CHCs changed prior to swarming for swarming preparation. Six CHCs were deferentially produced between PSC and RG. The differential profiles of CHCs with respect to different swarming states are currently under investigation.

Perturbation of normal behaviors (e.g., nursing and foraging) in honey bee colonies by any external factors would immediately reduce the colony’s capacity for brood rearing, which can eventually lead to collapse of entire colony. To investigate the effects of brood rearing suppression in the biology of honey bee workers (nurse and forager), the gene-set enrichment analysis (GSEA) was performed for the transcriptomes of worker bees with or without their brood rearing being suppressed, from which functional profiles of pathways under influences by each condition were identified. Blocking of normal labor (i.e., nursing or foraging) induced the over-representation of pathways related with reshaping of worker bee physiology, suggesting that transition of labor is physiologically reversible. In addition, brood rearing suppression appeared to result in the reduction of neuronal excitability and aggressiveness in both forager and nurse, which would be necessary to manage the in-hive stress under unfavorable conditions

There are two different types of acetylcholinesterase (AChE1 and AChE2) in the western honeybee as in most of insects. It is suggested that soluble AmAChE1 might be related with a stress response as judged from its elevated expression level in honey bee workers when brood rearing was suppressed. In this study, to ensure the nature of AmAChE1 responding to stress factors, the expression patterns of AmAChE1 following heat shock, brood rearing suppression and chemical treatments (Imidacloprid and fluvalinate) were investigated. Also, several heat shock protein (hsp) genes (hsp10, hsp60, hsp70 and hsp90) known as general stress markers were tested as positive references. Heat shock induced expression of every tested hsp along with AmAChE1. In brood rearing-suppressed worker bees, 7 days old bees showed much higher expression level of AmAChE1 and hsp90 compared to control honey bees. However, treatment of imidacloprid and fluvalinate did not induce any apparent overexpression of these genes. These results confirm that both HSP and AmAChE1 genes generally respond to temperature and brood rearing suppression and further suggest that AmAChE1 can serve as a potential biomarker along with hsps for the detection of stress in honey bee colonies.

We investigated pollination and foraging activities of honeybee (Apis mellifera L.) and bumblebee (Bombus terrestris L.) during flowering season of the asian pear (Pyrus pyrifolia N.) under different weather conditions. There was no significant statistical difference about the pollination activities of two species. However, the pollination activities of bumblebee were more active than those of honeybee under low temperature and rainfall period. The activities of honeybee and bumblebee were more influenced by temperature than other factors (i.e. illumination and wind velocity). Honeybee was more sensitive to temperature and illumination than bumblebee. At low temperatures (<20℃) on cloudy days (<30,000 lux) with a certain wind velocity (>4.0 m/s), the pollination activity of the honeybee was lower twice than that of bumblebee.

Honey bee swarming is a natural phenomenon that occurs when the colony encounters changes in the in-hive (i.e. population size and queen condition) and environmental conditions. To better understand the molecular basis of swarming, we conducted the transcriptomic profiles of worker bees between before swarming [pre-swarming colony (PSC)] and after swarming [swarming group (SG) and remaining group (RG)]. Based on the gene set enrichment analysis (GSEA), we predicted the biological processes associated with swarming. In addition, we analyzed the composition of cuticular hydrocarbons (CHCs) by gas chromatography-mass spectrometry and compared their profiles between different bee groups. GSEA results showed that there were a little differences between PSC and RG while many of the pathways related with metabolism and protein processing were down regulated in SG relative to PSC and RG. CHCs profiling revealed a similar CHCs composition between PSC and RG but some differences in CHCs composition (i.e. heneicosane, octacosane, octacosanol) were detected between SG and RG. These differences in gene pathway and CHC composition were discussed with respect to physiological changes and social communication.

Colony collapse disorder (CCD), a phenomenon of honeybees disappearance, has been reported since 2006. Chronic exposure to neonicotinoid insecticides, particularly imidacloprid, has been suggested to impair forager’s ability for foraging and be a main cause of CCD. Recently, it has been reported that imidacloprid induces insulin resistance in animal cell line by blocking glucose uptake. Similarly to human insulin, insulin-like peptide (ILP) of insects is involved in maintaining blood glucose contents in hemolymph by regulating the concentration of trehalose and glycogen. Therefore, we have hypothesized that sublethal concentration of neonicotinoid may affect the metabolic pathway of honey bees as well. We investigated the transcription levels of the genes involved in the insulin/insulin-like signaling (IIS) pathway, such as AmILP and AmInR, following an acute or a chronic dietary exposure of sublethal concentrations of imidacloprid to foragers. In both experiments, honeybees showed increased expression levels of ILP and InR in a dose-dependent manner. Our results suggest that sublethal dose of imidacloprid likely upregulates IIS pathway, thereby rendering honey bees to become resistant to insulin.

Two different types of acetylcholinesterae (AChE1 and AChE2) are present in majority of insects, including the Western honey bee. Out of the two honey bee AChEs (AmAChEs), the soluble AmAChE1 with little catalytic activity is widely distributed in both neuronal and non-neuronal tissues, including fat body. In this study, to identify stresss factors that can induce AmAChE expression, we tested various conditions that honey bees can encounter in natural setting, including heat shock, cold shock, bacterial challenge (Escherichia coli and Staphylococcus aureus) and Varroa mite infestations, and evaluated their effects on AmAChE expression. Among the stress factors tested, only heat shock condition induced AmAChE expression in a dose dependet manner. This finding suggests that one function of AmAChE1 is related with thermoregulations, especially against heat shock stress in honey bees.

Acetylcholinesterase 1 (AmAChE1) has low catalytic activity and is abundantly expressed in both neuronal and non-neuronal tissues. In previous experiments, we observed that AmAChE1 is rarely expressed in summer while highly expressed in winter. Through additional experiments, the expression of AmAChE1 was suggested to be associated with brood rearing status. Under the assumption that abnormal suppression of brood rearing activity may result in stressful condition in honey bee social community, it was further suggested that AmAChE1 is likely involved in stress management particularly during winter. We hypothesized that the increased docility usually observed in overwintering bees is likely an outcome of stress management in colony, which is mediated by AmAChE1 expression. To verify this, worker bees expressing abundant AmAChE1 were collected in early winter and injected with Amace1 dsRNA to knockdown Amace1. Then, the behavioral activity of the bees was investigated using the EthoVison video tracking system. Honey bees injected with Amace1 dsRNA showed significantly increased motility, which was strongly correlated with the suppressed expression level of AmAChE1 in the abdomen. No apparent reduced expression of AmAChE1 in the head was observed perhaps due to the limited efficacy of RNA interference in the blood-brain-barrier. Our finding suggests that behavioral activity can be regulated, at least, by AmAChE1 expression level in non-neuronal tissue (i.e., fatbody) perhaps via metabolic alteration.

Five heat shock protein 70 (hsp70) isoforms (hsc70-3, hsc70-4, hsc70-5, hsc70cb, hsp70Ab) of Apis mellifera were identified from Honeybee genome database. Specific primers for each isoform were designed for the quantitative realtime RT-PCR analysis, then analyzed transcript levels of the abdomen of adult workers (3-4 weeks old) in respond to heat shock and imidacloprid ingestion. Heat shock at 45°C for 1 h induced all 5 genes but highest in hsc70cb, hsp70Ab. Ingestion of imidacloprid pesticide did not change any hsp70 isoforms at 33°C but those bees also highly responsive to heat shock at 45°C. In addition, expression level of each hsp70 isoform was various and heat shock response of each isoform was tissue-specific. For example, hsc70-3 was highest in midgut, hsc70-4 was in hypopharyngeal gland, but hsp70Ab was in fat bodies. However, heat shock response of all 5 isoforms was the highest in the fat body than brain, hypopharyngeal gland, midgut, flight muscle and integument. Our results provide information for the understanding of complicated protective mechanism of honey bee against thermal stress.

Varroa destructor and Tropilaelaps mercedesae mites are ectoparasitic to honey bee having similar life cycle and damage symptoms. Both invade into the last instar larval cell and reproduce during capped brood period of honey bee development. Female adult mites escape from the comb cell on the back of the emerging adult bee (phoretic period) and invade another cell for reproduction. Objective of this study was to study the effect of competitive interaction on each parasitic mite species population. We assessed population monitoring of host and parasitic mites. Honey bee population was monitored by approximating sealed brood and adult bees based on the coverage of the combs. Parasitic mites were monitored by detection technique like sugar shake, stick board, and sealed brood. This monitoring continued at weekly interval during 2008, 2014, and 2015. Additionally Invasion distribution of each species was checked. We calculated carrying capacity, population growth rate, and competition parameter from population monitoring data. Single parasitic mite, Varroa occurred and infestation increased continuously throughout the year in 2008. Co-occurrence of Varroa and Tropilaelaps in honey bee colonies was studied in 2014 and 2015. Carrying capacity was higher in single parasite infesting honeybee than parasites in co-occurrence. While using sugar method, carrying capacity of Varroa alone was found higher than in its co-occurrence with Tropilaelaps. Population growth rate of Varroa when tested alone was higher than its co-occurrence with Tropilaelaps in sugar method. Population growth rate of Varroa and Tropilaepas was higher in sticky method than sugar methods when they were tested in co-occurrence. Population growth rate is higher in Tropilaelaps (0.09) than Varroa (0.05) when both are tested in co-occurrence. We calculated competition parameter of Varroa and Tropilaelaps which was 1.9 and 0.53, respectively. Negative effect on regulation of carrying capacity and population growth rate is due to interspecies competition. Varroa population was higher than Tropilaelaps because there was high intraspecies competition among Tropilaelaps. Single Varroa or its co-occurrence with Tropilaelaps both can destroy honeybee colonies.

꿀벌은 화분매개 산업으로 가장 각광을 받고 있는 곤충 중 하나이다. 현재는 서양뒤열벌, 머리뿔가위벌 등이 화분매개로 많이 이용되며 앞으로 다른 화분매개 곤충을 연구하여 화분매개 산업을 발전 시켜나가 농가와의 시너지효과를 기대할 수 있다. 현대에 들어 화분매개 산업에 문제시 되는 농약의 독성에 대한 피해가 늘어나고 있는데 미래의 화분매개충이 될 확률이 높은 stingless bee와 꿀벌간의 급성 독성에 대한 차이를 알고자 태국 치앙마이 대학교에서 stingless bee를 포획하여 네오니코티노이드계 3종(Thiamethoxam, Imidacloprid, clothianidin과 카바메이트계 1종(Cabaryl)에 대해서 섭식독성 실험을 하였다. 농약별 추천 농도에 맞게 희석 한 후, 10배부터 100,000배 6단계로 나누어 처리 하였다. Stingless bee의 반수치사농도는 Thiamethoxam, Imidacloprid, clothianidin에 대해 각각 049, 5.84, 0.72 ppm이었고, Cabaryl 처리구에서는 처리후 14시간까지 추천농도에서도 20%대의 사망률을 보였다. 반면 A. mellifera의 반수치사농도는 각각 0.22, 1.97, 0.46, 53.6 ppm로 나타났다. A. mellifera 국내 개체군을 대상으로 한 연구에서는 0.19, 6.32, 0.22, 7.84 ppm으로 나타났다. 꿀벌의 경우 개체군간 차이는 매우 적었으며, stingless bee의 경우 독성이 상대적으로 낮게 나타났다.

꿀벌(honey bee)은 대표적인 화분매개곤충으로 산업적 가치가 높을 뿐만 아니라 생태계에서도 중요한 위치를 차지한다. 2006년 이후 꿀벌군집붕괴현상(CCD)으로 인해 수많은 꿀벌들이 죽었지만 아직까지 그 정확한 원인이 밝혀지지 않아 여전히 꿀벌들의 생존을 위협하고 있다. 이와 더불어 최근 기후변화에 의한 불확실한 환경조건 또한 꿀벌을 위협하는 요소들 중 하나이다. 본 실험에서는 이러한 외부 환경 조건에 대한 꿀벌의 생리적인 반응을 측정하기 위해서 heat shock protein (hsp) 유전자를 이용하였다. 꿀벌의 유전체 분석을 통하여 36개의 hsp 유전자를 선발하였다. 이들 중 hsp40, hsp70, grp78, hsp90를 선정하여 quantitative real-time PCR를 통해 발현량을 분석하였다. 고온 처리(40, 45, 50°C)를 했을 때 45°C에서 hsp 발현량이 가장 높았다. 그리고 조직별(지방체, 중장, 날개 근육)로는 날개근육에서 발현량이 가장 높았다. 적화제 섭식 시 hsp 발현량이 증가하였지만, 살충제 이미다클로프리드 섭식 시는 hsp 발현량이 감소하였다. 즉, 외부 스트레스에 대해 꿀벌 hsp 유전자들의 발현이 다양한 패턴을 나타냈다. 이를 바탕으로 스트레스에 반응하는 꿀벌의 생리에 대해 더 폭넓은 이해가 있을 것으로 예상된다.

Although it is believed that internal nutrient sensors play important roles in feeding behaviors, their molecular and neural mechanisms underlying of the modulation of physiological status and cell growth are poorly understood. Using a Ca2+ imaging experiments with heterologous expression systems, we show that one of the gustatory receptors in the western honey bee Apis mellifera is selectively tuned to amino acids. Remarkably, we report that this gustatory receptor of the honey bee is highly expressed in hypopharyngeal gland, which plays a role in caste differentiation as well as royal jelly production and secretion. Knocking down this gustatory receptor gene reduces cellular pathways responsible for nutritional sensing such as mTOR signals in hypopharageal gland. Furthermore, the interfering expression of this gustatory receptor gene not only alters morphological changes and developmental retardation of the hypopharyngeal gland, but it also blocks cellular growth signals to induce autophagy. This new report indicates that internal sensing and downstream signals detecting nutrients is essential for honey bee to maintain the cellular growth and development of internal organs essential for caste development and maintenance of social structure in the honey bee.