최근 몇 년 전부터 우리나라의 양봉농가에는 전에 경험하지 못했던 이상기후 악재와 초비극 상황인 꿀벌 군집 붕괴현상(Colony collapse disorder, CCD)으로 인하여 최대 60% 이상의 꿀벌이 폐사하거나 사라지는 등 양봉산업 의 막대한 손실을 초래하였다. 본 연구는 복잡하고 다양한 원인으로 약해진 꿀벌의 면역력과 봉군 세력을 향상시 키기 위하여 농업부산물 홍삼박을 활용한 화분떡을 자가제조하여 꿀벌 사양 먹이를 통한 봉군 세력에 어떠한 영향을 미치는지를 구명하고자 수행하였다. 가공부산물 홍삼박을 건조하여 130 mesh 이상 초미립자로 분쇄하 였으며, 조사포닌 725 mg 100-1을 함유하였고 화분떡 총중량의 0.5, 1.0, 2.5, 5.0, 10.0%로 첨가하여 완전하게 혼합 배합하여 화분떡을 제조하였다. 분봉벌은 4월 분봉한 봉군으로 이용하였으며, 2달 동안 1주일 간격으로 대조구 화분떡과 제조한 홍삼박 화분떡 5처리구에 급이하여 봉군의 세력을 조사하였다. 사양 먹이로 급이한 화분떡은 30일간 달관조사에서 대조구와 처리구 모두 꿀벌 먹이로 거부반응은 없었다. 봉군 세력 조사로 4월 분봉벌의 봉군은 1매 2갈로 시작하여 약 한 달 후에 6매 봉판으로 증소되었으며, 이때 조사된 봉군별 봉개율은 대조구 55%(100 기준) 대비 홍삼박 0.5~1.0% 처리구는 58~60%로 +(5~9)% 향상되었던 반면, 홍삼박 2.5% 이상 첨가한 처리구에서는 봉개율이 -(9~20)% 감소하는 경향을 보였다. 그리고 화분떡 먹이 소모량을 조사한 결과, 대조구 평균 96.9%(100) 소모율 대비 홍삼박 0.5% 처리구는 97.7%로 다소 높았으나 홍삼박 2.5% 이상 처리구에서는 점점 감소하는 경향을 보였다.

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.

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.

Honey bee swarming is a naturally occurring phenomenon under the conditions of population increase, climate change and pollen deficit. However, unexpected swarming usually results in loss of bee colony, it poses a considerable trouble in bee keeping. In an attempt to search for molecular markers that can predict the swarming behavior, transcriptional profiling was conducted and compared between the heads of swarming group and the remaining group in the same honey bee colonies. A total of 25,551 transcripts were initially identified and 1,144 differentially expressed genes between the two groups were sorted by FC2 (fold change) cut-off value. Several transcripts, including 6 apidermin (structurally novel cuticular protein)-related, 16 cuticular and 3 odorant binding proteins, showed lower expression levels in the swarming group compared with the remaining group (FC range of –2.17 to –667.48, -2.04 to –54.34 and -2.08 to –21.34 respectively). Pathway analyses are currently in progress to understand the physiological and metabolic differences between swarming and remaining groups of honey bees.