Mortality of honeybees(Apis cerana) is a serious problem that beekeepers have to face periodically in Korea. The presence of RNA viruses, in addition to other pathogens may be one of its possible causes. In this work, we were detected Black queen cell virus (BQCV), Kashmir bee virus (KBV), Korean Sacbrood virus (KSBV), Ascosphaera apis, and Nosema in samples of Apis cerana. Honey bee viruses was detected KSBV(58.5 %), KBV(6.5 %), BQCV(70 %) in 2015 by RT(Revers transcriptase)-PCR. Sacbrood virus (SBV) is an important disease of A. cerana. A. apis can cause chock brood disease to honey bee. It was detected 10.3 % of A. cerana colonies by PCR. Also, Nosema cerana was detected 50.5%. Conclusively, investigated disease of the A. cerana, and confirmed virus that lead to bee disease, this is thought by valuable thing as data for development of beekeeping industry such as Colony Collapse cause searching examination.
Several Mites are currently the most serious threat to the world bee industry. The ectoparasitic honey bee mites was originally confined to the Asian honey bee(Apis cerana etc.). Varroa destructor and Tropilaelaps clareae has plagued European honey bees, Apis mellifera. Differences in mite tolerance are reported between two honey bee species A. mellifera and A. cerana. We were amplified antimicrobial peptide cDNA genes (Defencin, Abaecin, Royalisin, Apidaecin and Hymenoptaecin) by RT-PCR. We explored the transcriptional response to mite parasitism in A. mellifera 4th instars larvae which differ in susceptibility to V. destructor and T. clareae, comparing parasitized and non-parasitized 4th instars larvae (worker and Drone) from same hive. Differential gene expression of worker bees and Drone bees induced by mites (V. destructor and T. clareae) infection was investigated by northern blot. Mites (V. destructor and T. clareae) parasitism caused changes in the expression of genes related to sex distinction. Bees tolerant to mites (V. destructor and T. clareae) were mainly characterized by differences in the expression of genes regulating antimicrobial gene expression. It provides a first step toward better understanding molecular expression involved in this differential sex distinction host-parasite relationship. We were detected bee virus in A. mellifera, comparing parasitized and non-parasitized 4th instars larvae (worker and Drone). Therefore, this result was demonstrated that mites were another possible route of horizontal transmission, as several viruses were detected in mites and their hosts.
The ectoparasitic honey bee mites was originally confined to the Asian honey bee(Apis cerana etc.), mites had become widely established in the world and have continued to cause extensive bee colony deaths. Mites attach to adults and developing brood, where they feed on their blood. If left untreated, mites can deform bees and eventually kill the colony. Varroa destructor and Tropilaelaps clareae has plagued European honey bees, Apis mellifera. Differences in mite tolerance are reported between two honey bee species A. mellifera and A. cerana. We were counted number of mites(V. destructor and T. clareae) form 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.
South Korea has over 38 millions of managed honey bee (Apis cerana) colonies before 2009 years ago, which produce the highest quantity of honey in the Korea; however, almost colony (99%) were collapsed by Korean Sacbrood Virus (KSBV) in South Korea. Korean Sacbrood Virus (KSBV) is the pathogen of A. cerana Sacbrood disease, which poses a serious threat to honeybee A. cerana, and tends to cause bee colony and even the whole apiary collapse. Colony collapse of A. cerana was first reported on the Pyeong-Chang of the South Korea in 2009. Symptoms of KSBV include the rapid transmission of larval stage honeybees (A. cerana), many dead larvae found in the bottom of hive and comb. Honeybees (A. cerana) are a very important species because they provide a number of pollination services for various ecosystems in some provinces (ex. jeon-nam, jeon-buk province). They are also extremely important organisms within human society, both agriculturally and economically. The fact that a direct cause has been determined suggests that colony collapse is a complex problem with a combination of natural and anthropogenic factors. Possible instigators of colony collapse include: wax moth, viral and fungal diseases, increased population, decreased genetic diversity, climate changing and a variety of other factors. The interaction among these potential causes may be resulting in immunity loss for honeybees and the increased likelihood of collapse.
Sacbrood disease is a viral disease on honey bee larvae Apis cerana. Diseased larvae fail to pupae and to be dead at old larvae and pre-pupae stage. Currently, there is no remedy to control sacbrood disease. In this study we conducted to observe sacbrood disease on Apis cerana colonies from June to September, 2014 at the A. cerana apiary of NAAS, and using biological measure to treat this disease. Our study results were showed that sacbrood disease infected A. cerana colonies in all months of observation. The percentage of infected colonies was from 33.3% up to 100%. Controlling sacbrood disease by requeen measure, the percentage of recovered colonies was 57.1 % while of this by cage queen measure was only 28.6 %.
In this study we conducted to rear worker honey bee (Apis cerana) from larvae to adult stage in the laboratory by using plastic well plates. Our study results were showed that honey bee larvae Apis cerana could be reared in the laboratory. The adult worker bee started to emerge on day 17 from grafting. The emergence of worker bee peak on day 18 and declined thereafter. The average survival rate from larvae to pre-pupae stage was 74.6%. The average survival rates from pre-pupae to adult stage and from larvae to adult stage were 40.7 % and 30.4 % respectively.
Asian is rich in honey bee species and genetic diversity. Among the difference native honey bee species, Apis cerana is very diversity of subspecies and distribution as well. Until now, nine A. cerana subspecies have been named. However, natural diversity of this species is being declined by threats such as pest, disease, deforestation, pesticide positioning and climate change. Therefore, the understanding of morphological characteristics of A. cerana is viral for maintaining biological diversity. In this paper we give an overview of method that are used for distinguish honey bee A. cerana subspecies and ecotype that can contribute to recognize genetic origin of colonies for conservation and breeding purpose. Base on morphmetric method currently in use, we outline strategies for sampling and measuring morphological characteristics on A. cerana.
Cockroaches are insects of the order Blattodea, sometimes also called Blattaria, of which about 30 species out of 4,600 total are associated with human habitats. About four species are well known as pests. Among the best-known pest species are the American cockroach, Periplaneta americana, which is about 30 mm long; the German cockroach, Blattella germanica, about 15 mm long. We researched growing condition of in-vitro(temperature and humidity) for P. americana and B. germanica. The cockroach is divided in three sections; the body is flattened and broadly oval, with a shield-like pronotum covering its head. A pronotum is a plate-like structure that covers all or part of the dorsal surface of the thorax of certain insects. They also have chewing mouth parts, long, segmented antennae, and leathery fore wings with delicate hind wings. The third section of the cockroach is the abdomen. We measured size of head, abdomen, and body length during differential stages. Also, we checked number of egg, size of egg, hatching rates, period of former laying eggs, and laying periods etc.
Vitellogenins (Vgs) are precursors of the major egg storage protein, vitellin (Vn), in many oviparous animals. Insects Vgs are large molecules (200-kD) synthesized in the fat body in a process that involves substantial structural modifications (e.g., glycosylation, lipidation, phosphorylation, and proteolytic cleavage, etc.) of the nascent protein prior to its secretion and transport to the ovaries. However, the extent to which Vgs are processed in the fat body varies greatly among different insect groups. We were cloned Vgs partial genes PaVgs and BgVgs from Periplaneta americana and Blattella germanica. Real-time quantitative PCR shows that PaVgs and BgVgs were differential-regulated with aging. In insects, glutathione S-transferases (GSTs) are enzymes involved in detoxification of insecticides. We were cloned GST partial genes PaGST and BgGST from Periplaneta americana and Blattella germanica. Real-time quantitative PCR shows that PaGST and BgGST were up-regulated with aging, and the mRNA level of PaGST and BgGST was higher in 4℃ and 37℃ than room temperature. The expression level of PaGST and BgGST exposure to temperature stress suggests that PaGST and BgGST are up-regulated after exposure low and hige temperature treatments.