• Journal of Forest and Environmental Science
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• v.33 no.4
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• pp.342-347
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• 2017

Since the first report of the oak wilt disease at 2004 in Korea, the disease distributed over Korean peninsula and are still giving severe damages. The management of oak wilt disease in Korea has mainly focused on the control of insect vector, Platypus koryoensis. Neverthless the effective method for evaluating the pathogenicity of the pathogen, Raffaelea quercus-mongolicae (Rqm), and for screening chemical or biological agents with strong inhibitory activity against the pathogen, is absolutely necessary, an reliable method is not available so far. This study was conducted to develop the effective method for evaluating the pathogenicity of Rqm in oak trees. The culture suspensions of Rqm were artificially injected to the saplings of Quercus acutissima by using ChemJet tree injector. Three months after treatments, the treated saplings were cut and dipped into 1% fuchsin acid solution. There were significant differences in non-conductive area (%), discoloration area (%) and vertical discoloration length between the pathogen-injected and distilled water-injected control treatments. These results indicated that the pathogen is the causal agent for the dysfunction of water conductive tissue, which will finally result in wilt symptom. Re-isolation of the pathogen and PCR detection using specific primers for the pathogen also confirmed the presence of Rqm in the sapwood chips of the pathogen-injected saplings. These observations would be greatly applied to other related researches for evaluating the pathogenicity of tree wilt pathogens and biocontrol efficacy of the selected antagonistic microorganisms, in case that the wilt symptom is not easily shown by artificial inoculation of the causal agent.

• International Journal of Industrial Entomology and Biomaterials
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• v.23 no.2
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• pp.231-238
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• 2011

Attacin is an insect antibacterial protein that plays an important role in immune response to injury and infection. In this report, we have isolated and characterized of cDNA encoding for the attacin from the immunized larvae of swallowtail butterfly, $Papilio$ $xuthus$. A full length cDNA of $P.$ $xuthus$ attacin was obtained by employing annealing control primer (ACP)-based differential display PCR and 5' RACE. The complete $P.$ $xuthus$ attacin cDNA was comprised of 949 bp encoding a 250 amino acid precursor. It contains a putative 18 amino acid signal peptide sequence, a 42 amino acid propeptide sequence, and a 190 amino acid mature protein with a theoretical molecular mass of 19904.01 and a pI of 9.13. The putative mature protein of $P.$ $xuthus$ attacin showed 48-52% and 24-30% identity in amino acid sequences with that of lepidopteran and dipteran insects, respectively. Semiquantitive RT-PCR results revealed that the transcript of $P.$ $xuthus$ attacin gene was up-regulated at significant levels after injection with bacterial lipopolysaccharide (LPS). We sub-cloned cDNA fragment encoding mature $P.$ $xuthus$ attacin into the expression vector, highly expressed in $E.$ $coli$ BL21 cells, and its antibacterial activity was analyzed. Recombinant $P.$ $xuthus$ attacin evidenced considerably antibacterial activity against Gram-negative bacteria, $E.$ $coli$ ML 35 and $Klebsiella$ $pneumonia$.

• Entomological Research
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• v.48 no.5
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• pp.384-389
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• 2018

Aphis gossypii Glover is an important insect pest that functions as a viral vector and mediates approximately 45 different viral diseases. As part of a strategy for control of A. gossypii, we investigated the functions of genes using RNAi. To this end, a cDNA library was constructed for various genes and for selecting appropriate targets for RNAi mediated silencing. The cDNA library was constructed using the Gateway cloning system with site-specific recombination of bacteriophage ${\lambda}$. It was used to carry out single step cloning of A. gossypii cDNAs. As a result, a cDNA library with a titer of $8.4{\times}10^6$ was constructed. Since the sequences in this library carry att sites, they can be cloned into various binary vectors. This library will be of value for various studies. For later screening of selected genes, it is planned to clone the library into virus-induced gene silencing (VIGS) vectors, which makes it possible to analyze gene function and allow subsequent transfection of plants. Such transfection experiments will allow testing of RNAi-induced insecticidal activity or repellent activity to A. gossypii, and result in the identification of target genes. It is also expected that the constructed cDNA library will be useful for analysis of gene functions in A. gossypii.

• International Journal of Computer Science & Network Security
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• v.23 no.9
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• pp.77-90
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• 2023

Today, crops face many characteristics/diseases. Insect damage is one of the main characteristics/diseases. Insecticides are not always effective because they can be toxic to some birds. It will also disrupt the natural food chain for animals. A common practice of plant scientists is to visually assess plant damage (leaves, stems) due to disease based on the percentage of disease. Plants suffer from various diseases at any stage of their development. For farmers and agricultural professionals, disease management is a critical issue that requires immediate attention. It requires urgent diagnosis and preventive measures to maintain quality and minimize losses. Many researchers have provided plant disease detection techniques to support rapid disease diagnosis. In this review paper, we mainly focus on artificial intelligence (AI) technology, image processing technology (IP), deep learning technology (DL), vector machine (SVM) technology, the network Convergent neuronal (CNN) content Detailed description of the identification of different types of diseases in tomato and potato plants based on image retrieval technology (CBIR). It also includes the various types of diseases that typically exist in tomato and potato. Content-based Image Retrieval (CBIR) technologies should be used as a supplementary tool to enhance search accuracy by encouraging you to access collections of extra knowledge so that it can be useful. CBIR systems mainly use colour, form, and texture as core features, such that they work on the first level of the lowest level. This is the most sophisticated methods used to diagnose diseases of tomato plants.

• Korean journal of applied entomology
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• v.63 no.1
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• pp.77-80
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• 2024

Aedes albopictus, a common species in the Republic of Korea, is internationally known as a major vector for various diseases, and it is well-adapted to urban environments. Recent insect outbreaks in urban areas, attributed to climate change and urban heat islands, have increased the necessity of researching the effects on mosquito populations. This study analyzed climate data from 25 Automatic Weather System (AWS) stations in Seoul, identifying urban areas with pronounced heat island effects and suburban areas with milder effects. Nine urban heat island conditions were established based on this analysis, under which the hatching rates of Ae. albopictus were examined. The results revealed an increase in hatching rates correlating with the intensity of the urban heat island effect. Regression analysis further indicated that this trend accelerates as the strength of the heat island effect increases. This study suggests that temperature variations resulting from urban heat island phenomena can significantly influence the hatching rates of Ae. albopictus.

• Journal of Preventive Medicine and Public Health
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• v.2 no.1
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• pp.77-80
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• 1969

In the cities nowadays, the dwelling conditions of Cackroach are provided by use of various kinds of construction material, installation of heating and cooling facilities that maintain moderate temperature, filthy sanitation, and lack of knowledge about insect as mechanical Vector. Cakroach is infectious disease Vector, and it proves to be of much importance in the public health. Considering such importance, the author has surveyed the distribution of Cackroach in the housing areas of Seoul City from May 1969 to the end of August 1969, and has come to the following conclusion: 1. House dwelling Cackroach collected in the City of Seoul are of two species, i. e. Blatella Germanica Linneaus and Periplaneta Japonica Karny. 2. Most of cackroach collected in Seoul are Blatella Germanica Linneaus and they are distributed in whole area of Seoul while that of Periplaneta Japonica Karny is distributed only in the limited area. 3. Dwelling places of Blatella Germanica Lineaus are in grog shop, Korean food restaurants, bakery shops, and patient rooms in hospitals. Many of them are found in tile kitchens and dining rooms of restaurants, and tearooms. They live in groups at older houses with much crack, warm and humid places. 4. For method of collection, the hand collection was the most effective. In trap collection during the day time, when the trap is placed at the narrow corners off the ground after confirming the dwelling places of cackroach, the match trap was more effective than the flask trap in collecting. In case of collecting during the night time, the flask trap was much more effective method than the match trap.

• Parasites, Hosts and Diseases
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• v.52 no.1
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• pp.93-97
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• 2014

Subolesin (4D8), the ortholog of insect akirins, is a highly conserved protective antigen and thus has the potential for development of a broad-spectrum vaccine against ticks and mosquitoes. To date, no protective antigens have been characterized nor tested as candidate vaccines against Dermacentor silvarum bites and transmission of associated pathogens. In this study, we cloned the open reading frame (ORF) of D. silvarum 4D8 cDNA (Ds4D8), which consisted of 498 bp encoding 165 amino acid residues. The results of sequence alignments and phylogenetic analysis demonstrated that D. silvarum 4D8 (Ds4D8) is highly conserved showing more than 81% identity of amino acid sequences with those of other hard ticks. Additionally, Ds4D8 containing restriction sites was ligated into the pET-32(a+) expression vector and the recombinant plasmid was transformed into Escherichia coli rosetta. The recombinant Ds4D8 (rDs4D8) was induced by isopropyl ${\beta}$-D-thiogalactopyranoside (IPTG) and purified using Ni affinity chromatography. The SDS-PAGE results showed that the molecular weight of rDs4D8 was 40 kDa, which was consistent with the expected molecular mass considering 22 kDa histidine-tagged thioredoxin (TRX) protein from the expression vector. Western blot results showed that rabbit anti-D. silvarum serum recognized the expressed rDs4D8, suggesting an immune response against rDs4D8. These results provided the basis for developing a candidate vaccine against D. silvarum ticks and transmission of associated pathogens.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.501-511
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• 2016

Predicting potential spatial distribution of Monochamus alternatus, a major insect vector of the pine wilt disease, is essential to the spread of the pine wilt disease. The purpose of this study was to predict future domestic spatial distribution of M. alternatus by using the CLIMEX model considering the temperature condition of the vector's life history. To predict current distribution of M. alternatus, the administrative divisions data where the pine wilt spots caused by M. alternatus were found from 2006 to 2014 and the 10-year mean climate observed data in 68 meteorological stations from 2006 to 2015 were used. Eight parameter sets were chosen based on growth temperature range of M. alternatus reported in preceding researches. Error matrix method was utilized to select and simulate the parameter sets showing the highest correlation with the actual distribution. Regarding the future distribution of M. alternatus, two periods of 2050s(2046-2055) and 2090s(2091-2100) were predicted using the projected climate data of RCP 8.5 Scenario generated from Korea Meteorological Administration. Overall results of M. alternatus distribution simulation were fit in the actual distribution; however, overestimation in Seoul Metropolitan area and Chungnam Region were shown. Gradual expansion of M. alternatus would be expected to nationwide from western and southern coastal areas of Korea peninsula.

• The Plant Pathology Journal
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• v.35 no.4
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• pp.381-388
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• 2019

For several years, temperatures in the Korean peninsula have gradually increased due to climate change, resulting in a changing environment for growth of crops and vegetables. An associated consequence is that emerging species of insect vector have caused increased viral transmission. In Jeju Island, Korea, occurrences of viral disease have increased. Here, we report characterization of five newly collected turnip mosaic virus (TuMV) isolates named KBJ1, KBJ2, KBJ3, KBJ4 and KBJ5 from a survey on Jeju Island in 2017. Full-length cDNAs of each isolate were cloned into the pJY vector downstream of cauliflower mosaic virus 35S and bacteriophage T7 RNA polymerase promoters. Their fulllength sequences share 98.9-99.9% nucleotide sequence identity and were most closely related to previously reported Korean TuMV isolates. All isolates belonged to the BR group and infected both Chinese cabbage and radish. Four isolates induced very mild symptoms in Nicotiana benthamiana but KBJ5 induced a hypersensitive response. Symptom differences may result from three amino acid differences uniquely present in KBJ5; Gly(382)Asp, Ile(891)Val, and Lys(2522)Glu in P1, P3, and NIb, respectively.

• Journal of Korean Society of Forest Science
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• v.102 no.2
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• pp.170-175
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• 2013

This study was conducted to investigate the effect on the habitation of Monochamus alternatus, a vector insect of Pine wood nematode by the tended sound stumps for the developing forestry control methods of Pine wilt disease controls. Field cage plots (1 m ${\times}$ 1 m ${\times}$ 1 m) were established 12 units (Experiment1:4 units, Experiment2:8 Units) and were treated 4 kinds(February in 2010, February, April, June in 2011). The adults of M. alternatus were put into 4~5couples each the cage June in 2011. Presence or absence of the larva entrance holes and larva were detailed November in 2011. The larva were appeared in the sound stumps of sapling and young trees tended at February, April, June, the current emergence year of M. alternatus, but were not appeared in the sound stumps of sapling and young trees tended February in 2010, one year before the emergence of M. alternatus. The larva habitated in stumps of sapling were likely to be smaller in size in compare to the larva in stumps of young trees. In case of young tree, the larva were found at the cleft part of bark, but were not found at ridge part of bark. All observed larva appeared at part of bark and between the bark and the woody parts, but were not found at the woody parts. To develop the control guiding principal of sound stump after forest tending practice, further experiment need is in existence oviposition and larvae of vectors by height of stemps.