• Journal of fish pathology
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• v.26 no.3
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• pp.129-137
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• 2013

The study surveyed infection rate of Kudoa septempunctata parasitized in the trunk muscle of olive flounder, Paralichthys olivaceus, cultured in Jeju Island and wild fish species caught in the coastal area around Jeju Island during 2012. Among 143 olive flounder that were randomly sampled from 26 different culture farms, K. septempunctata was detected in 7 fish samples (4.9%) from 4 different culture farms, showing no typical Kudoa infestation. However, K. septempunctata was not detected in olive flounder fry sampled from hatcheries and 8 species of wild fish. In addition, we compared 3 different sampling sites on trunk muscle of 7 Kudoa positive fish that included head part, tail part and entire muscle. Among 7 fish, K. septempunctata was detected in 3 fish that were sampled from head part; while 4 fish from tail part of trunk muscle. However, all 7 fish were positive when sampled from entire muscle. Thus, we suggest that it will be more efficient to use entire muscle sample than sampling partial muscle parts for detection of K. septempunctata.

• Research in Plant Disease
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• v.25 no.3
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• pp.124-130
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• 2019

The study was conducted to investigate the infestation and distribution of plant-parasitic nematodes on Chinese yam (Dioscorea batatas) in Andong, Korea. Root-knot nematodes, Meloidogyne incognita was the most prevalent nematode species which is found from 43 yam fields (81.1%) with high population densities (average of 450 juveniles/$300cm^3$). Other nematodes, root-lesion nematode (Pratylenchus spp.) and pin nematode (Paratylenchus spp.) were less problematic. Density of juveniles (J2) of M. incognita was $10\;J2/300cm^3$ by August, then increased to 274 in September and 624 in October. The highest J2 density was found at the soil depth between 40 and 50 cm ($1,840\;J2/300cm^3$). M. incognita was able to infest yam tuber down to a depth of 70 cm and developed galls outside and brown spots inside. The highest number of females were found at 40-50 cm (79 females/10 cm piece) tuber from the top.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.522-528
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• 2018

Saemimyeon, a Tongil type, medium-late maturing rice variety, is especially used for preparing rice noodles. Its high amylose content was developed to fit market demands and to be affordable for rice processing industries. One of the high yielding lines, Milyang181 (Hanareum), was used in the final three-way cross of $IR50^*2$/YR18241-B-B-115-1-1 for yield improvement and cultivation stabilization, including disease resistance. YR24235-10-1-3, a high yielding and compact plant type, was selected and named Milyang278 after yield test at NICS (RDA, Miryang) in 2010. It was subjected to regional yield test at six sites in the middle and southern plain areas of South Korea. Saemimyeon heading occurs on August 12 and is a mid-late maturing cultivar, with resistance to leaf blast, rice stripe virus, and bacterial blight (K1-K3a), but it is susceptible to major diseases and insect pest infestation. Saemimyeon showed a high amylose content of 26.7%, with a relatively low KOH digestion value of 3.5, which are key factors in rice noodles and pasta processing. In the local adaptability tests, the yield of Saemimyeon was 7.08 MT/ha-an increase of approximately 106% compared to that of Dasan. Thus, Saemimyeon is suitable for cultivation in the southern and middle plain areas of South Korea.

• Food Science and Industry
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• v.50 no.2
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• pp.2-11
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• 2017

Packaging is the last defensive barrier that protects food products from insect infestation during storage. However, though packaging films are hermetically sealed, insects can still be attracted by strong olfactory cues and penetrate through packaging materials, resulting in contamination. Insect contamination may cause consumers to be repulsed by contaminated food products. Especially, it is well known that stored-product insects cause critical problems in the cereal industry by inducing quantitative and qualitative damages to the grain products. The contaminations are caused by insects' metabolic byproducts and body parts, consequentially caused customer repulsion. Therefore, it is necessary to repel and control insects. However, management systems for storage insects in food industry have been inadequate for many years. Synthetic pesticides has been widely used, but pesticides may accumulate in foods, causing acute and chronic symptoms in consumers. For this reason, there is a growing need for the development of natural insecticides that can replace synthetic pesticides. Thus, various reports about anti-insect packaging materials and strategies to repel insects were introduced in this study. Furthermore, we suggested new strategies to develop an insect-repelling active packaging materials which could be applied in the food packaging industry.

• Parasites, Hosts and Diseases
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• v.59 no.6
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• pp.625-634
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• 2021

Based on the field investigations in 91 investigation sites (counties) in southwest China between 2001 and 2019, the present paper reported the chigger mites on A. agrarius mice in southwest China for the first time by using a series of statistical methods. From 715 striped field mice captured in 28 of 91 investigated sites, only 255 chiggers were collected, and they were identified as 14 species, 6 genera in 3 subfamilies under 2 families. Of 715 A. agrarius mice, only 24 of them were infested with chigger mites with low overall prevalence (P_M=3.4%), overall mean abundance (M_A=0.36 mites/host) and overall mean intensity (M_I=10.63 mites/host). The species diversity and infestation of chiggers on A. agrarius were much lower than those previously reported on some other rodents in southwest China. On a certain species of rodent, A. agrarius mouse in southwest China seems to have a very low susceptibility to chigger infestations than in other geographical regions. Of 14 chigger species, there were 3 dominant species, Leptotrombidium sialkotense, L. rupestre and Schoengastiella novoconfuciana, which were of aggregated distribution among different individuals of A. agrarius hosts. L. sialkotense, one of 6 main vectors of scrub typhus in China, was the first dominant on A. agrarius. The species similarity of chigger mites on male and female hosts was low with C_SS=0.25, and this reflects the sex-bias of different genders of A. agrarius mice in harboring different chigger species.

• Research in Plant Disease
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• v.29 no.1
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• pp.45-51
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• 2023

The study was conducted to investigate the infestation and distribution of plant-parasitic nematodes on kiwi orchards in Korea. Plant parasitic nematodes genus and densities were investigated at a total of 102 sites in Jeollanam-do, Gyeongsangnam-do, and Jeju-do, which are the main production areas of domestic kiwi orchards. Plant parasitic nematodes detected were of 9 genera, including root-knot nematodes (Meloidogyne spp.), spiral nematodes (Helicotylenchus spp.), and needle nematodes (Paratylenchus spp.), and 56% of the 102 plantations were infected with root-knot nematodes. Root-knot nematodes were found to be the most important plant parasitic nematode in domestic kiwi orchards. The average density of root-knot nematodes is 97 per 300 cm³ soil, and there is concern about the kiwi yield reduction. As a result of identifying the root-knot nematode species: M. arenaria, M. hapla, M. incognita, and M. javanica. Among them, M. arenaria is the most dominant. As the plant parasitic nematode infection route in fruit trees is often spread through the transplantation of infected seedlings, attention should be paid to the production of nematode-free plants during the production and supply of kiwifruit plants.

• Korean journal of applied entomology
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• v.62 no.3
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• pp.215-220
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• 2023

A recent discovery of drywood termites (Cryptotermes domesticus) in a residential facility in Seoul has raised significant concern. This exotic insect species, which can damage timber and wooden buildings, necessitates an immediate investigation of potential infestation. In this study, we assessed the climatic suitability for this termite species using a species distribution modeling approach. Global distribution data and bioclimatic variables were compiled from published sources, and predictive models for climatic suitability were developed using four modeling algorithms. An ensemble prediction was made based on the mean occurrence probability derived from the individual models. The final model suggested that this species could potentially establish itself in tropical coastal regions. While the climatic suitability in South Korea was generally found to be low, a careful investigation is still warranted due to the potential risk of colonization and establishment of this species.

• Korean journal of applied entomology
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• v.62 no.3
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• pp.139-147
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• 2023

Leaf-spray in vitro bioassays appraise new aphicidal formulations for managing deleterious plant-feeding aphids. The formulation may utilize alternative and integrated strategies. However, leaf spraying even under controlled conditions may affect aphid reproduction and mortality. This study examines leaf spray applications for optimum and reproducible aphicidal results using tobacco leaves overlaid on cotton fabric or water agar surfaces. Infestation of the undersides of tobacco leaves with nymphs of green peach aphids was used in the assays. Spray distance and volume were optimized using water-sensitive paper to ascertain the best surface coverage. Overlays of the leaves on water agar caused less mortality and greater reproduction than the use of cotton fabric. The relative humidity of the insect-rearing chambers changed with the watering regime for the insect - rearing chambers with cotton fabric; 60% relative humidity was optimal. Relative humidity was not affected by the concentration of agar in the water agar chambers. Applications of the chemical aphicidal standard, Sulfoxaflor, under the optimized conditions exhibited similar times for lethality although the rate was faster with leaves on the cotton fabric than on water agar. These studies establish reproducible and sensitive techniques for assessing the lethality and effects on reproduction of potential aphicidal products.

• Journal of the Korean Wood Science and Technology
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• v.52 no.3
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• pp.262-275
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• 2024

In Indonesia, Coptotermes curvignathus Holmgren and Cryptotermes cyanocephalus Light termite attacks can damage wood and causing losses of 8.7 trillion rupiah per year. Wood treatment and soil barrier are very important to protect structures and their components from termite infestation. The application of synthetic chemicals that pose risks to the environment and human health. The growing movement to replace these chemicals with new termiticides that are safe for the environment in place of persistent organic pollutants. Efficacy performance in entomopathogenic fungi spores such as that produce decanoic acid, hexadecanoic acid, palmitic acid, and octadecadienoic acid are potential compounds that provide for ecofriendly termite control. Entomopathogenic fungal spores from Metarhizium anisopliae, Trichoderma harzianum, and Beauveria bassiana, as the active ingredient were formulated with nanocellulose was added as an inert ingredient to which helped to deliver the active ingredients on controlling the target pest, and enhance the utility ability of the product fungi to control termites. The mortality of these termites successively entomopathogenic fungi was the main cause of death. The higher concentrations being associated with of nanocellulose used affect increased the number of termites mortality. M. anisopliae paired with 60% nanocellulose concentrate was the best percentage for yielded the greatest C. curvignathus and C. cynocephalus termite control. In the field testing, M. anisopliae provided better, it showed the finest result of termite control rather than B. bassiana and T. harzianum. The results of the research indicate that entomopathogenic fungi can be used for Pest Control Management as the subterranean termite and drywood termite control.

• Korean Journal of Veterinary Research
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• v.21 no.2
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• pp.105-112
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• 1981

The morphological and structural studios of Anisakinae larva has been carried out since Sept. of 1980. The larva were collected from naturally infested eleven swine of 1,531 examined at Kwang-Ju abattoir and from marine fishes, Somber japonicus, bought at Kwang-Ju fish market. The results observed were as follow : 1. Anisakis larva found in the stomach wall and on the surface of the mucosa were more or less degenerated. According to the progress of degeneration, the cross sections showed varied structures (Fig. 6, 7). 2. Size of the larva both from swine and fishes were measured respectively in average(mm); 18.0 and 18.7 in body length, 0.30 and 0.41 in body width, 1.64 and 1.68 in esophagus(muscular-part), 0.56 and 0.67 in ventriculus (glandular part), and 0.13 and 0.12 in tail. It was notable that body length of the larva in this present data, 18.0mm and 1.87mm, were shorter than those in previous dada, 24.3mm from human cases and 28.4mm from, however, the present data were almost similar to the data, 1.75mm, from swine case. 3. The Boring tooth, Mucron, long ventriculus and short round tail were observed in the larva of this present study. These structures were differentiated from Anisakis type II larvae which was provided with short ventriculus, and conical and tapering tall without mucron. 4. The ventricular appendix and intestnal caecum were not present in the larva. These might be differentiated from other Anisakidae larva such as Terranova larvae, Contracaecum larvae, Raphidascaris larvae and Thynnascaris larvae. 5. The findings through the histological observation were a pair of Y-shaped or butterfly-shaped lateal chords, ventral and dorsal chords, excretory(Renette) cell, high columnar epithelial cells of digestive tract and muscle cells. These morphological characteristics revealed varied features in the structures in the degenerative degree of the larva in the stomach wall. 6. The above-mentioned characteristics of the larva observed could be indentified as Anisakis type I larvae. 7. The reports on natural infestation of domestic animal with Anisakis type I larvae were two swine cases in Korea and Japan respectively, On the other hand two human cases of the larva were reported in Korea and more than one thousand cases in Japan. In Twiwan no reports of human and domestic animal cases could be found.