Showing papers in "Journal of Apiculture in 2008"

Economic Value of Honeybee Pollination on Major Fruit and Vegetable Crops in Korea

Abstract: Honeybee is the most important insect pollinator of agricultural crops as well as natural vegetation, which make the green earth sustainable. Even with vast amount of economic evaluation of pollination service from abroad, limited information is available in Korea. By adopting the methods of Robinson et al., economic value of pollination service provided by honeybee was estimated on major fruit and vegetable crops. The annual production for the selected crops was estimated as 12 billion USD. Approximately 50% of the annual production was turned out as the honeybee pollination service, amounting 5.8 billion USD. This is 18 times more than the annual primary production of Korean beekeeping (350 million USD). Further improvement of the estimation with more field data is required with consensus among stakeholders.

국내 꿀벌에서의 바이러스진단 및 질병발생 현황 조사

Abstract: Mortality of honeybees is a serious problem that beekeepers have to face periodically in Korea and worldwide. The presence of RNA viruses, in addition to other pathogens may be one of its possible causes. In this work, we detected Deformed wing virus (DWV), Israle Acute Paralysis Virus (IAPV), Black queen cell virus (BQCV), Cloudy wing virus (CWV), Kashmir bee virus (KBV), Sacbrood virus (SBV), Chronic bee paralysis virus (CBPV) in samples of korea honeybees with or without Varroa destructor and Nosema apis. The detection of viruses in all provinces, simultaneous co-infection of colonies by several viruses and the fact that 96.3% of the samples were infected with one or more virus, indicates they are widely spread in the region. Using uniplex and multiplex RT-PCR we screened honey bee colonies for the presence of several bee viruses, including DWV, IAPV, BQCV, KBV, CWV, and described the detection of mixed virus infections in bees from these colonies. Also, average spore number of Nosema apis was confirmed by 30,029 spores per 1 worker bee, and 128,750 spores were confirmed in Anseong that is 1,200, maximum place of infection in Gangneung that is lowest occurrence area. Average infection rate of chalk brood was 27.03%, and Cheorwon that is lowest infection area is 2.3% and Suncheon that is maximum infection area was 71.9%. Conclusively, investigated disease of the bee, and confirmed new virus that lead to bee disease, this is thought by valuable thing as data for development of beekeeping industry such as CCD (Colony Collapse Disorder)’s cause searching examination.

사과꽃의 방화곤충 및 방사한 화분매개곤충의 화분매개활동 특성

Abstract: This study was examined the characteristics of the foraging activities of Apis mellifera, Bombus terrestris and Osmia cornifrons, and compared them with the effect of artificial pollination in apple orchards. Our surveys on visited pollinators on apple flowers for pollen and nectar found 3 orders, 7 families and 13 species during the apple blossoming period in spring, 2004. Of all insect visitors, 89% were in Order Hymenoptera, 7% in Order Lepidoptera and 4% in Order Diptera. The peak time of foraging of A. mellifera was 10:00, B. terrestris was 14:00 and O. cornifrons 14:00. About 50% of A. mellifera collected nectar exclusively, 47% pollen and 3% both. B. terrestris collected pollen only, whereas 78% of O. cornifrons collected both nectar and pollen. The rate of fruit set on terminal flowers was varied according to the pollinators with A. mellifera 40.9%, B. terrestris 26.8%, O. cornifrons 51.3% and artificial (hand) pollination 26.7%. The weight of individual fruit did not differ according to the pollinators, but the weight of marketable fruit was 30% higher than artificial (hand) pollination. Furthermore, if we take account the cost of labour for artificial pollination, the use of pollinators saves time and trowble of 93%, remarkably.

Development of PCR Detection Method for Sacbrood Virus in Honeybee (Apis mellifera L.)

Abstract: A PCR method was developed to detect and verify Sacbrood Virus (SBV), which affects to honeybee larvae. The PCR assay was performed with SBV specific primer set and amplified 824bp fragment from SBV genome. The SBV amplicon containing a BamHI restriction site was digested by this enzyme for a brief verification of SBV infection. SBV3-842F/R primer set showed high specificity and sensitivity in detection of SBV. SBV amplicon was cloned and sequenced to make sure result of PCR and digestion. It showed 94% and 99% homology in nucleotide and amino acid sequence with SBV complete genome (AF092924), respectively. In this paper, we report a specific SBV primer pairs for detection and verification of SBV.

Influence of Different Colony Placement Distances on Yield and Quality Parameters of Peach(Prunus persica L.)

Abstract: Optimum pollination requirement of peach (Prunus persica L.) cultivar ‘Flordasun’ by placing Apis mellifera L. colony at different distances from the plants was evaluated vis-a`-vis their effect on quantitative and qualitative yield parameters at RRS, Karnal. A. mellifera foragers were maximum (36.6 9 bees/m2) at closest distances of 20m followed by 40m (30.9) and dwindled drastically to half (18.2) with the increase in distance to 70m and further (59.8%) at the farthest distance of 100m (14.7/m2). A positive and significant correlation was observed between colony distance, pollinator’s population and yield parameters. At the closest distance (20m), the fruit set was the maximum (6.5 fruits/branch), decreased marginally (6.1 fruits) at 40m and greatly at 70 and 100m (3.3 and 2.7 fruits/branch, respectively). The caged plants (without insect pollination) bore least number of fruits (1.6/branch) with lowest yields and 35.7percent branches had no fruit set at all. Whereas, at all the four distances evaluated, yield parameters significantly and overwhelmingly out-performed WIP treatment and had no barren branches. Fruit yield (per branch) was maximum at 20m (343g) followed by 40m (301.3g) with a marked reduction at 70 (141.3) and 100m (115.3g). At closer distance, the mean fruit weight was almost equal (51.1 and 49.4g) and was significantly lower (42.8 and 42.7g) at the farther distances but comparable to WIP (42.6g). At 100m, fruit yield was minimum (94.60q/ha) and increased to 104.18q at 70m (an increase of 110.1%). At 40m, the yields increased substantially to 240.90q (by 254.7%) and were maximum (259.33q/ha) at the closest distance of 20m (increase of 274.1%). Compared to WIP that has lowest yield of 49.78q/ha, increase in yield was 190.0% at 100m, 209.3% at 70m, a significant 483.9% at a still closer distance of 40m and a whooping 521.0% at the closest distance of 20m. Fruits of bigger size (4.0×4.6cm length) were harvested at closer distance and their length decreased by 6.5~8.7% at farther distance. However differences in breadth and TSS (%) were non-significant at different distances. Total economic gains were highest at 20m (Rs. 1,52,598/ha) and 40m (Rs. 1,41,540) and were only Rs. 59,508 and 53,760 at 70 and 100m whereas Rs. 29,868 in WIP. Placing colonies nearer the crop from 100 to 70m resulted in an additional income of Rs. 5,748. This increment was Rs. 57,912 at 40m and an astonishing Rs. 98,838/ha at 20m distance. Based on the effective area coverage by the bees, 2 colonies/ha (10-frame) optimally pollinated the peach but they shall be placed not farther than 40m from the orchard.

A Consideration on the Pollen Morphology of Walnut Trees (Juglans spp.) by Using Scanning Electron Microscope (SEM)

Abstract: This study was considered the differences among species and cultivars on pollen morphological characters of walnuts (Jugalns spp.) by scanning electron microscope (SEM). It was different only with the pollen size of walnuts among species and cultivars, and the pollens of walnuts were similar in terms of their pollen structure. For polar axis length (PL), ‘W33’, Japan cultivar having 46.05μm was the highest, whereas ‘Yangpyeong 2’, Korea selective cultivar having 27.18μm was the lowest. For equatorial diameter (ED) ‘Yongdong’, Korea cultivar having 46.05μm was the highest in this study, whereas ‘Yangpyeong 2’, Korea selective cultivar having 25.41μm was the lowest. For the number of pores (NP), ‘Nr. 139’, Germany cultivar having 18.40 was the highest, whereas ‘Muju 10’, Korea selective cultivar, having 12.20 was the lowest. In conclusion, the information obtained from this work was that pollen grains of walnuts were mixed subprolate and prolate in equatorial view; showed more or less periporate than 15 pores in aperture type; were largely divided into two groups (J. regia and J. sinensis) and a outgroup (J. mandshurica and J. sieboldiana); were mainly PL and PL and ED ratio in morphological characters of principle component.

Flowering and Nectar Secretion Characteristics of Honey Palnt, Hovenia dulcis var. koreana Nakai

Abstract: In order to search a possibility of Hovenia dulcis var. koreana Nakai for honey plant, flowering and nectar secretion characteristics were investigated. Flowering was started after a month from 15 May when a flower stalk formed. Number of flower per fructify lateral of 52 clones shown much difference; 2,388 Maximum and 207 minimum. Nectar secretion was started with flowering at the same time and secretion was happened two times during two days after flowering. Amount of nectar from a one flower was 4.15±1.11μl. Estimated number of flower and secreted nectar volume at one individual tree were 719,670 ea and 2.98L, respectively. That nectar secretion result of H. dulcis var. koreana Nakai was shown much volume compared with Robinia pseudo.

Nosema 진단을 위한 Real-Time PCR 진단법의 개발

Abstract: Real-time detection method was applied to quantitative detection of Nosema which is widespread and cause extensive losses of adult bees. Using Nosema-specific primers, 590 nucleotide long fragment was amplified. Molecular cloning was performed with this amplicon. And then the clone was named Nosema-1. Nosema- 1 has 99.6% and 98.9% homology with Nosema ceranae small subunit ribisomal RNA gene (GenBank Accession no. DQ486027) nucleotide sequence and protein sequence, respectively. For quantitative realtime PCR, a specific detection primer set (Nosema-RT-F/R) was designed and evaluated. The unique 180bp DNA fragment was quantitatively amplified using specific primer pair. In the real-time PCR assays with serially diluted template and artificially contaminated template, the specific quantitative real-time PCR showed high sensitivities which were able to detect 101 copies in the both standard assays. Also, this method can detect not only to be used for DNA condition but also to be applied for real honeybee samples.

화분매개곤충 이용현황 실태조사

Abstract: The current status of insect pollinator use was surveyed. Honeybee was larger than mason bee and bumblebee in average use area per farm household at kinds of insect pollinator. Insect pollinator was used at 19 crops. Among them, tomato was the most used crop, which was 44.9%, and in order to apple 26.7%, strawberry 13.1%, red-pepper 7.7% and watermelon 3.7%. In the use of insect pollinators, bumblebee, which was 56.9%, was higher than honeybee (31.3%) and mason bee (11.8%). The most farmers were a positive intention except for 1.5% of farmer in the use of insect pollinator for crop pollination. The best advantage in insect pollinator use was improvement of seed setting percentage, which was 28.3% and the worst problem was low activity at bad weather, which was 25.8%. And also, 97% of farmers have an intention to use continuously insect pollinator.

꿀벌 성충에 기생하는 꿀벌응애(Varroa destructor Anderson and Trueman)의 개체군 증가 모델 I. 지수증가모델

Abstract: The exponential population growth modelling was tried from the population monitoring data of honeybee mite, Varroa destructor from Andong National University apiary. Varroa mite population began to increase exponentially from early July to late Augsust, 2008 when no mite control tactics was applied. However from the late August, population increase was a bit lowered mostly because of the deficiency of the phoretic hosts, the honeybee adults. At the end, most of the adult honeybee collapsed with the same destiny of the brood in late September. Population growth rate was estimated as 0.08 during increase phase which was much higher than the parameter known from the West. The possible causes were searched. Even with this simplicity of the model structure, this type of analytical model can enhance our understanding of the varroa mite biology and its management. Some aspects of its utilization was discussed.

국내 꿀벌에서의 Sacbrood Virus (SBV) 진단

Abstract: Sacbrood virus (SBV) causes a fatal disease (sacbrood) of honeybee larvae, which fail to pupate, change color and shape, and finally die. The complete nucleotide sequence of SBV has recently been determined, and with these data, we now report a Reverse Transcription-PCR (RT-PCR) test for the direct, rapid, and sensitive detection of these viruses. To detect the SBV infection in Korea, we collect beekeepers from various apiaries, which the RT-PCR technique was used. And we designed SBV specific primers in conserved region of the viral genome in the GenBank database. We confirmed the SBV amplicon using cloning and sequence. Homology between determined sequences of SBV korean strain and published virus sequences were 97% in DNA sequcence, and 100% in amino acid sequence. We describe the first time that presence of sacbrood virus (SBV) in korea honey bee colonies using RT-PCR. We also developed and validated a RT-PCR assay for the detection of SBV in Korea.

꿀벌응애(Varroa destructor)를 통한 꿀벌 바이러스의 진단

Abstract: 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.

Black Queen Cell Virus 진단을 위한 Real-Time PCR 진단법의 개발

Abstract: A real-time PCR technique was developed for the detection and the quantification of black queen cell virus (BQCV) which is one of fatal viral pathogens against queen larvae. For the technique, a specific detection primer set (BQCV-RT-F/R) was designed and evaluated. The unique 159bp fragment was amplified with this BQCV-specific primer pair. In the real-time PCR assays with serially diluted template and artificially contaminated template, the primer set showed high sensitivities which were able to detect 10¹ copies in the both standard assays. As we respected, it was convinced that real-time PCR results from fluorescence curves were more sensitive than ones of electrophoretic analysis. BQCV could be detected by using this newly developed real-time PCR, which would induced a strong advance for the control and the prevention of BQCV in honeybees.

Minus-strand-specific RT-PCR에 의한 Chronic Bee Paralysis Virus(CBPV) 진단

Abstract: Viruses of the honeybee, Apis mellifera L. are known to reside at low levels in colonies, typically showing no apparent signs of infection. Chronic paralysis virus (CBPV) is known to induce significant losses in honey bee colonies. The pathology is characterized by clusters of trembling, flightless, crawling bees and by individual bees, sometimes hairless, standing at the hive entrance. A minus-strand-specific RT-PCR was used to assess viral replication. This is the first report on the infection of CBPV in Korea. Using (-) RTPCR, 27 apiaries in korea were screened for the honeybee viruses, with positive colonies being analysed for viral genetic diversity. We got PCR product of two different size using two different primer from CBPV RNA1. PCR product size is 570-nt (AM-CBPV1-1). Nucleotide sequences were aligned to the complete CBPV RNA1 sequence deposited in the GenBank database and were revealed 96.84%(AM-CBPV identity, respectively. Amino acid were aligned to the CBPV RNA1 sequence deposited in GenBank database and were revealed 95.26% identity, respectively. Sequence comparison with other CBPV and honeybee virus.

한국 과수 및 채소 작물 생산에서 꿀벌 화분매개의 경제적 가치 평가

Abstract: 꿀벌의 화분매개가 농업 생산에 미치는 경제적 기여를 추정하기 위하여 Robinson 등의 방법을 이용하였다. 선택된 국내 주요 과수 및 채소작물의 연 생산액은 약 12조원으로 파악되었고, 이 중에서 꿀벌 화분매개를 통해 파생된 생산액은 5.9조원으로 추정되었다. 즉 선택된 작물의 약 50%가 꿀벌의 화분매개를 통해 이루어 졌다는 의미이며, 이는 국내 1차 양봉생산액(3500억)의 약 18배에 이르는 수준이다. 또한 많은 작물에서 화분매개를 위한 봉군 임대 또는 꿀벌봉군을 투여할 경우, 손익은 과채류의 30여배에서 과수에서는 30~300배 정도로 추산되었다. 추후 보다 객관적이며 구체적인 자료 확보를 통하여 꿀벌의 경제적 가치를 올바르게 평가하고, 이에 합당한 양봉 산업 진흥을 위한 정책 개발이 필요하다.

Evaluation of Chemical Susceptibility for the Ectoparasitic Mite Varroa destructor Anderson and Trueman (Mesostigamata: Varroidae) in Honeybee (Apis mellifera L.)

Abstract: The varroa mite is now a serious threat for the beekeeping industry in the world. Because of the strict regulation of synthetic chemical residues in honeybee products, beekeepers are searching the safe way of pest management to minimize the use of chemicals. In this study, the efficacy of chemicals was tested against varroa mites. The efficacy of chemicals was compared by the whole hive and bioassay kit methods. Among the chemicals, tau-fluvalinate was most effective followed by amitraz and flumethrin. Coumaphos and flavonoid+citric acid showed lower efficacies in summer and fall treatment. Also among the environmentfriendly materials, formic acid and thymol showed the higher efficacies. From the results, it was suggesting that bioassay kit testing is more cost-effective than the whole hive treatment. From this history of beekeepers’ chemical uses, tau-fluvalinate was mostly used and frequency of chemical use was estimated around six to ten per year. Further research involvement in chemical efficacy testing was discussed.

서양뒤영벌(Bombus terrestris)과 호박벌(B. ignitus)에 대한 병원성 세균 분리

Abstract: Bumblebees are important pollinators in greenhouse and have colonized all parts of the World. In Korea, the value of bumblebees is increasing as pollinator. However, the more recent use of reared colonies may ultimately allow pathogens to spread to peripheral areas for Bombus spp. So, we report pathogenic bacteria isolated from Bombus terrestris and B. ignitus at first time in Korea. Bacillus fusiformis and Klebsiella oxytoca are isolated from B. terrestris and confirmed with 16S rRNA gene nucleotide comparison in NCBI genebank. Pathogenicity of B. fusiformis was 35~40% against B. terrestris. Pantoea dispersa and K. oxytoca are isolated from B. ignitus and confirmed with 16S rRNA gene nucleotide comparison in NCBI genebank. Pathogenicity of these species were 35~40% against B. ignitus.

밀원수종 헛개나무의 개화 및 화밀분비 특성

Abstract: In order to search a possibility of Hovenia dulcis var. koreana Nakai for honey plant, flowering and nectar secretion characteristics were investigated. Flowering was started after a month from 15 May when a flower stalk formed. Number of flower per fructify lateral of 52 clones shown much difference; 2,388 Maximum and 207 minimum. Nectar secretion was started with flowering at the same time and secretion was happened two times during two days after flowering. Amount of nectar from a one flower was 4.15±1.11μl. Estimated number of flower and secreted nectar volume at one individual tree were 719,670 ea and 2.98L, respectively. That nectar secretion result of H. dulcis var. koreana Nakai was shown much volume compared with Robinia pseudo.

새로 발견된 밀원식물들

Abstract: Newly found honeyplants were described from 2003 to 2007 by observation near Daegu city. They were Cardamine leucantha, Idesia polycarpa, Ilex macropoda, Grewia biloba var. parviflora, Sapium sebiferum, Lirioope platyphylla. Ulmus parvifolia. Saussurea pulchella, Orostachys japonicus, Osmanthus heterophyllus. Characteristics and morphology of each plant were described.