SEM Observations of Korean Haloptype Varroa destructor (Acari: Varroidae) Collected from Apis mellifera Colonies

Ratna Thapa,Siriwat Wongsiri,Myeong Lyeol Lee,Yong-Soo Choi,Young-Joon Ahn,Hyung Wook Kwon 한국양봉학회 2015 韓國養蜂學會誌 Vol.30 No.3

Scanning electron microscopic observations on the Korean haplotype of Varroa destructor collected from Apis mellifera was indentifed by mtDNA analysis to describe external morphology K-type V. destructor. SEM micrographs showed that the K-type V. destructor is more oval than Japan/Thai- Vietnam type and has three kinds of setae viz, serrated, spiny, and smooth marginal setae. The marginal setae are somewhat flexible. The K-type V. destructor is larger than V. jacobsoni and V. rindereri. The peritreme of K-type V. destructor is smaller than V. jacobsoni and V. rindereri. No sternal pores were observed in the K-type V. destructor, which is present in V. jacobsoni and V. rindereri. The K-type V. destructor has a more metapodal setae than V. jacobsoni and V. rindereri.

Transcriptome sequencing and construction of in silico cDNA library of honeybee mite, Varroa destructor

Woo Jin Kim,Seok Hee Lee,Fang Ying,Jong Hoon Kim,Dong Hwan Park,Ra Mi Woo,Min Gu Park,Jae Young Choi,Yeon Ho Je 한국응용곤충학회 2016 한국응용곤충학회 학술대회논문집 Vol.2016 No.10

Varroa destructor is a devastating ectoparasitic mite which attacks Honeybee, Apis mellifera. V. destructor feeds on honeybee hemolymph, and often harbors small RNA viruses such as the deformed wing virus to transmit these viruses in the infested bee hive. To survey the genes of V. destructor, total RNA was subjected to high-throughput transcriptome sequencing to construct in silico cDNA library by using the Illumina HiSeq 2000 platform. Total of 2×107,748,792 paired-end short reads were obtained and quality filtered reads were subjected to Trinity de novo assembler followed by TransDecoder, and CD-HIT program to make a V. destructor reference cDNA library containing 28,023 of clustered contigs with protein coding capacity. These cDNA sequences will help us to understand the molecular biology of V. destructor.

Analyzing Gut Microbial Community in Varroa destructor-Infested Western Honeybee (Apis mellifera)

Minji Kim,Woo Jae Kim,Soo-Je Park The Korean Society for Microbiology and Biotechnol 2023 Journal of microbiology and biotechnology Vol.33 No.11

The western honeybee Apis mellifera L., a vital crop pollinator and producer of honey and royal jelly, faces numerous threats including diseases, chemicals, and mite infestations, causing widespread concern. While extensive research has explored the link between gut microbiota and their hosts. However, the impact of Varroa destructor infestation remains understudied. In this study, we employed massive parallel amplicon sequencing assays to examine the diversity and structure of gut microbial communities in adult bee groups, comparing healthy (NG) and Varroa-infested (VG) samples. Additionally, we analyzed Varroa-infested hives to assess the whole body of larvae. Our results indicated a notable prevalence of the genus Bombella in larvae and the genera Gillamella, unidentified Lactobacillaceae, and Snodgrassella in adult bees. However, no statistically significant difference was observed between NG and VG. Furthermore, our PICRUSt analysis demonstrated distinct KEGG classification patterns between larval and adult bee groups, with larvae displaying a higher abundance of genes involved in cofactor and vitamin production. Notably, despite the complex nature of the honeybee bacterial community, methanogens were found to be present in low abundance in the honeybee microbiota.

Evaluation of the Attractive Effects on Insect Pheromones for Varroa destructor

Sara Park,Sewoong An,Hye Kyung Kim 한국양봉학회 2023 韓國養蜂學會誌 Vol.38 No.4

Honey bees play important roles in the maintenance and preservation of agricultural ecosystems in that they contribute to fruit and seed production by pollinating crops. However, ectoparasitic mites, Varroa destructor, cause considerable damage to honey bee colonies. V. destructor is a major problem for apiculture, and the search for novel control methods is an essential task for researchers. Therefore, we carried out an experiment with twenty insect pheromones, which are well known for their function and structure, to develop an attractant for effectively controlling V. destructor during the phoretic phase. For the study, we investigated the attractive effects of 40 different pheromones. From the preliminary screening (Z)-8-dodecenyl acetate ((Z)-8-12:Ac), (E)-8-(E)-10-dodecenyl acetate (E)-8, (E)-10-12:Ac), (E)-11-tetradecenyl acetate ((E)-11-14:Ac) and (Z)-11-tetradecenyl acetate ((Z)-11-14Ac) showed relatively good attraction effect for V. destructor. For the four selected pheromones, the attraction effect was tested at 50 mg, 25 mg, 12.5 mg, and 6.25 mg concentrations to check the concentrationdependent responsiveness. [Z]-8-12:Ac, [E]8, [E]10-12:Ac were found to have a higher attraction effect than other pheromones. After then, the two selected pheromones were tested the attraction effect of pheromone exposure time, and the attraction effect of both pheromones was lasted up to 3 hours. Although this study was also considered the effect of pheromone chemical structure on V. destructor, there was no chemical structure-dependent attraction. However, (Z)-8-12:Ac and (E)-8, (E)-10-12:Ac were found to have relatively high attraction effects depending on pheromone concentration and exposure time. Therefore, these pheromones should be further investigated as potential alternative attractant for V. destructor control. In addition, further studies are warranted to determine the synergistic effects among different components, and establish appropriate delivery methods to develop safer and more effective attractant.

Analyzing Gut Microbial Community in Varroa destructor-Infested Western Honeybee (Apis mellifera)

Kim Minji,Kim Woo Jae,Park Soo-Je 한국미생물·생명공학회 2023 Journal of microbiology and biotechnology Vol.33 No.11

The western honeybee Apis mellifera L., a vital crop pollinator and producer of honey and royal jelly, faces numerous threats including diseases, chemicals, and mite infestations, causing widespread concern. While extensive research has explored the link between gut microbiota and their hosts. However, the impact of Varroa destructor infestation remains understudied. In this study, we employed massive parallel amplicon sequencing assays to examine the diversity and structure of gut microbial communities in adult bee groups, comparing healthy (NG) and Varroa-infested (VG) samples. Additionally, we analyzed Varroa-infested hives to assess the whole body of larvae. Our results indicated a notable prevalence of the genus Bombella in larvae and the genera Gillamella, unidentified Lactobacillaceae, and Snodgrassella in adult bees. However, no statistically significant difference was observed between NG and VG. Furthermore, our PICRUSt analysis demonstrated distinct KEGG classification patterns between larval and adult bee groups, with larvae displaying a higher abundance of genes involved in cofactor and vitamin production. Notably, despite the complex nature of the honeybee bacterial community, methanogens were found to be present in low abundance in the honeybee microbiota.

꿀벌응애에 대한 신규화합물 K16776의 살비효과

오만균(Man-Gyun Oh),안희근(Hee-Geun Ahn),김현경(Hyun-Kyung Kim),윤창만(Changmann Yoon),김진주(Jin-Ju Kim),김태준(Tae-Joon Kim),이동국(Dong-Guk Lee),정근회(Geun-Hoe Chung),김길하(Gil-Hah Kim) 한국농약과학회 2008 농약과학회지 Vol.12 No.2

This study examined the acaricidal activity of a new compound, K16776 against honeybee mite, Varroa destructor which is ecto-parasite of Apis mellifera. Acaricidal activity was performed using six acaricides, two Chinese commercial acaricides and one newly synthesized K16776 against V. destructor in the small container and in the bee hive. K16776 and amitraz exhibited 100% acaricidal activity against V. destructor without insecticidal toxicity to A. mellifera in the small container. The other acaricide was not activity. Applied to the bee hives, K16776 showed acaricidal activity as 98.7% (250×) and 88.6% (500×) and amitraz showed as 100% (500×) and 90% (1,000×), respectively. Made in China, Cao Suan Sha Man Pian and Wangs showed acaricidal activity as 56.9% and 66.7%, respectively. The result indicates that K16776 can be potentially useful control agent against honeybee mite, V. destructor.

Development of single nucleotide polymorphism markers specific to Apis mellifera (Hymenoptera: Apidae) line displaying high hygienic behavior against Varroa destructor, an ectoparasitic mite

김종석,김민지,김혜경,Nguyen Ngoc Vung,김익수 한국응용곤충학회 2019 Journal of Asia-Pacific Entomology Vol.22 No.4

To control Varroa destructor, an ectoparasitic mite, a honey bee line possessing high hygienic behavior (HHB) against this mite has been bred in South Korea. However, a method that can diagnose and assess the HHB line from control (the low hygienic behavior, LHB) line has not been reported yet. Thus, the objective of this study was to develop single nucleotide polymorphism (SNP) markers through whole-genome sequencing of worker bees from HHB line of A. mellifera caucasica and LHB line of A. m. carnica (Hymenoptera: Apidae). A total of 319,445,977 sequence reads were mapped to the known A. mellifera reference genome (average coverage of 87.46%). In 2,316,128 and 3,266,756 SNPs from HHB and LHB line, respectively, 20 SNPs that showed homozygosity in each line were selected and eight SNPs were used to diagnose the HHB line either by typical PCR-restriction fragment length polymorphism or allele-specific PCR. Six of remaining SNPs were of different sizes, enabling relatively easy differentiation of these two honey bee lines on typical agarose gel. Another remaining six SNPs had different sequences, including SNP sites. These SNP markers can be used to diagnose and assess V. destructor-specific HHB line of honey bees.

Antibacterial Peptide Gene Expression and Virus Transmission in the Honey Bee (Apis mellifera Feb.) by Varroa destructor Infestation

Yong-Soo Choi,Man-Young Lee,In-Pyo Hong,Soon-ok Woo,Ha-Sik Sim,Gyu-Ho Byuon,Ratna Thapa,Myeong-Lyeol Lee 한국양봉학회 2013 韓國養蜂學會誌 Vol.28 No.4

The varroa mite (Varroa destructor Anderson and Trueman) is currently the most serious threat to the world bee industry. This ectoparasitic honey bee mite was originally confined to the Eastern honey bee, Apis cerana, but now plagues the European honey bee, Apis mellifera. Differences in mite tolerance are reported between these two honey bee species. We amplified antimicrobial peptide cDNA genes (Defensin, Abaecin, Royalicin, and Hymenoptaecin) by RT-PCR in order to explore the transcriptional response to mite parasitism in A. mellifera, which differs in susceptibility to varroa mites, by comparing parasitized and non-parasitized full-sister adult bees (worker bees, drone bees) from the same hive. Differential gene expression in worker and drone bees induced by varroa infestation was investigated by northern blotting. Varroa mite parasitism caused changes in the expression of genes related to sex distinction. Bees tolerant to viruses from varroa mites were mainly characterized by differences in the expression of genes regulating antimicrobial gene expression. This finding provides a first step towards a better understanding of the molecular expression involved in this differential sex distinction host-parasite relationship. We detected bee virus in A. mellifera by comparing parasitized and non-parasitized full-sister adult bees (worker bees, drone bee). Therefore, this result demonstrated that varroa mites were another possible route of horizontal transmission and induction of antibacterial gene expression.

꿀벌응애(Varroa destructor)를 통한 꿀벌 바이러스의 진단

최용수(Yong-Soo Choi),이명렬(Myeong-Lyeol Lee),이만영(Man-Young Lee),이광길(Kwang-Gill Lee) 한국양봉학회 2008 韓國養蜂學會誌 Vol.23 No.3

Bee parasitic mite syndrome is a disease complex of colonies simultaneously infested with Varroa destructor mites and infected with viruses and accompanied by high mortality. By using reverse transcriptional PCR (RT-PCR), W′ve out of seven bee viruses were detected in mite samples (V. destructor) collected from Korea. Samples of Varroa destructor samples were collected at the end of summer following acaricide treatment. In Varroa destructor mites, during the year viruses were found at least sevevn viruses (DWV, IAPV, KBV, CBPV, SBV, CWV, BQCV) of the apiaries. The latter findings support the putative role of mites in transmitting these viruses. Taken together, these data indicate that bee virus infections occurpersistently in bee populations despite the lack of clinical signs, suggesting that colony disease outbreaks might result from environmental factors that lead to activation of viral replication in bees. This is also the first report of bee viruses in mites from Korea.

꿀벌에 기생하는 꿀벌응애(Varroa destructor)와 중국가시응애(Tropilaelaps clareae)의 형태적 특성과 생태적 상호작용

최용수(Yong-Soo Choi),이명렬(Myeong Lyeol Lee),심하식(Ha Sik Sim),김혜경(Hye Kyung Kim),변규호(Kyu Ho Byeon),윤미영(Mi Young Yoon),강아랑(Ah Rang Kang),트란 반 또안(Tran Van Toan),홍인표(In Pyo Hong),우순옥(Soon Ok Woo) 한국양봉학회 2014 韓國養蜂學會誌 Vol.29 No.4

The ectoparasitic honey bee mites was originally confined to the Asian honey bee (Apis cerana etc.). Mites attach to adults and developing brood, where they feed on the hemolymph. If left untreated, mites can deform bees and eventually kill the colony. Varroa destructor and Tropilaelaps clareae have plagued European honey bees, Apis mellifera. Differences in mite tolerance are reported between two honey bee species A. mellifera and A. cerana. We counted number of mites (V. destructor and T. clareae) from 20 colonies. V. destructor and T. clareae has very similar behavior in honeybee colony. When behaviorally close, two competing species may populational interfere, and thereby affect their population dynamics. We tested for populational interference (PI) between two populational competing honeybee mites, V. destructor and T. clareae, by investigating their population dynamics when they competed on the same colony. Population of V. destructors are increased during August, whereas population of T. clareaes are decreased. The effects of interspecific competition on the population growth of mites (focus in the colony) are summarized in data. The presence of T. clareae on with V. destructor led to reduce in the change of T. clareae population size at August compared with other season, indicating that some form of interspecific competition occurred between the two species.