• Journal of Microbiology and Biotechnology
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• v.26 no.3
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• pp.549-557
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• 2016

Aphids are a large group of hemipteran pests that affect the physiology, growth, and development of plants by using piercing mouthparts to consume fluids from the host. Based an recent data, aphids modulate the microbiomes of plants and thereby affect the overall outcome of the biological interaction. However, in a few reports, aboveground aphids manipulate the metabolism of the host and facilitate infestations by rhizosphere bacteria (rhizobacteria). In this study, we evaluated whether aphids alter the plant resistance that is mediated by the bacterial community of the root system. The rhizobacteria were affected by aphid infestation of pepper, and a large population of gram-positive bacteria was detected. Notably, Paenibacillus spp. were the unique gram-positive bacteria to respond to changes induced by the aphids. Paenibacillus polymyxa E681 was used as a rhizobacterium model to assess the recruitment of bacteria to the rhizosphere by the phloem-sucking of aphids and to test the effect of P. polymyxa on the susceptibility of plants to aphids. The root exudates secreted from peppers infested with aphids increased the growth rate of P. polymyxa E681. The application of P. polymyxa E681 to pepper roots promoted the colonization of aphids within 2 days of inoculation. Collectively, our results suggest that aphid infestation modulated the root exudation, which led to the recruitment of rhizobacteria that manipulated the resistance of peppers to aphids. In this study, new information is provided on how the infestation of insects is facilitated through insect-derived modulation of plant resistance with the attraction of gram-positive rhizobacteria.

• Korean journal of applied entomology
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• v.36 no.3
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• pp.237-242
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• 1997

Comparative studies on suppression possibility with three phytoseiid mite species (An.thly,seiu,sw omersleyi Schicha. A. ,fidIrrc~i.Gs arman and T\ulcornerphlorlrotiiu.s oc~c~idetitaliNs esbit) to the two-spotted spider mite (Te~trrrt~yc.Iir~l~l\ulcorner.i\c .(re Kwh) on kidney bean leaves in field and greenhouse were carried out. In the field experiments with the initial prey -predator ratio of 4 : 1. I0 : I and 20: I . A. ,firllrrcis suppressed successfully the prey populations at all three ratios 17 days after the initial infestation. A. wornc,r-;leyi \uppressed the prey population only at the ratio of 4 : 1, while T. oc~c~ideritcr1iw.s as unable to suppress the prey population at all tested ratios. In the greenhouse experiments with the initial prey-predator ratio of 10: 1, A. jil1ltrci.s could suppress the prey population continuously during the infestation period. A. ~~otnc~r,slceoyuil d suppress the prey population for 13 days after the initial infestation, while T. occie1mttrli.s could suppress the prey population for 8 - 23 days after the initial infestation.

• Journal of Forest and Environmental Science
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• v.26 no.2
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• pp.113-116
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• 2010

The Acacia seyal Del. var. seyal belongs to family Mimosaceae is known locally as gum Talha tree. It is a multipurpose tree species occurs throughout the African gum belt in Savannah mostly in pure forest. In Sudan it thrives on heavy clay soils that receive an annual rainfall between 400-800 mm. It is an important source of rural energy (fuelwood and charcoal) and forage. As mentioned by Nair (2007) the economic damage causes by insect in natural forest often difficult to judge due to no enough research attention The tree is frequently affected by biotic factors among them the insect pests. During a survey in the 1980's the tree was severely infested by the longhorned beetles (Cerambycidae) severely infesting other Acacia species, but the ecological data are overlooked. Therefore, the objective of the study was to assess infestation characteristics and to determine environmental factors triggering the attack of longhorned beetles. A temporary random sampling technique was applied to observe the damage characteristics of the longhorned beetles on tree species during May-July 2007. Five sample plots occupies by A. seyal were taken in Kordofan region directly observed for the presence of hole of emergence of the longhorned beetles, presence of dusts, presence of insect stages, girdling as well as other characteristics of damage. The study results indicate that the infestation rate of trees in the sampled sites ranged between zero and 23.08%. Further ecological researches are recommended.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.287-287
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• 2022

In this study, we analyze RNA-seq data from OxF3Hand WT at several points (Oh, 3 h, 12 h, and 24 h) after WBPH infection. A number of the genes were further validated by RT-qPCR. Results revealed that highest number of DEGs (4,735) between the two genotypes detected after 24 h of infection. Interestingly, many of the DEGs between the WT and OsF3H under control conditions were also found to be differentially expressed in OsF3H in response to WBPH infestation. These results indicate that significant differences in gene expression between the "OxF3H" and "WT" exist as the infection time increases. Many of these DEGs were related to oxidoreductase activity, response to stress, salicylic acid biosynthesis, metabolic process, defense response to pathogen, cellular response to toxic substance, and regulation of hormones level. Moreover, genes involved in salicylic acid (SA) and Ethylene (Et) biosynthesis were upregulated in OxF3H plants while jasmonic acid (JA), Brassinosteroid (Br), and abscisic acid (ABA) signaling pathways were found downregulated in OxF3H plant during WBPH infestation. Interestingly, many DEGs related to pathogenesis such as OsPR1, OsPR1b, NPR1, OsNPR3 and OsNPR5 were found significantly upregulated in OxF3H plants. Additionally, genes related to MAPKs pathway, and about 30 WRKY genes involved in different pathways were found upregulated in OxF3H plants after WBPH infestation. This suggests that overexpression of the OxF3H gene leads to multiple transcriptomic changes and impact plant hormones, pathogenic related and secondary metabolites related genes and enhancing the plant resistance to WBPH infestation.

• Korean Journal of Veterinary Research
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• v.42 no.4
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• pp.531-536
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• 2002

A total of 576 fatteners selected randomly from 6 Korean native goat farms in Chonnam area were examined for louse infestation from March 1997 to February 1998. The lice collected from the goats were identified. Four goat farms were selected and 20 goats were randomly chosen from each farm; blood samples were taken from the goats seasonally and examined hematologically and chemically. It was found that 495 out of 576 goats (85.9%) were infested with lice. The infestation rate in one of the 6 farms reached 92.9%. Two species of lice were identified; Linognathus sp. (sucking lice) and Bovicola sp. (biting lice). Goats infested with lice showed higher values in white blood cell, neutrophil and eosinophil counts than the goats not infested counterparts; same trend was seen with total protein, albumin and globulin concentrations. The results of this study indicate that louse infestation in the goat should be investigated extensively in view of the goat farming.

• Journal of Life Science
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• v.7 no.4
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• pp.347-354
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• 1997

Some attempts were made to investigate the gentic characteristics of the brown planthopper(BPH), Nilaparvata lugens Sta${\aa}$l, biotypes. In terms of egg and nymphal periods, egg hatcgability, emergence ratio, and population change of BPH and plant damage of rice cultivars by the infestation of BPH biotypes and their hybrid progenies in field conditions. The egg and nymphal periods of the three of BPH biotypes and their hybrid progenies on Dongjinbyeo with no resistance gene were shorter than on rice cultivars with resistance gene. But the periods of biotype-2(♀) X 2(♂) (E) on Samgangbyeo with Bph-1 gene and biotype-3(♀) X 3(♂)(I) on Mirying 63 with bph-2 gene were as short as on Dongjinbyeo. The egg hatchability and emergence ratio of the three Bph biotypes and their hybrid progenies on Dongjinbyeo were higher than on the other rice cultivars, and those of E on Samgangbyeo and I on Miryang 63 were as high as on Dongjinbyeo. In rice paddy field, biotype-1(♀) X 1(♂)(A)$\sim$I infested on Dongjinbyeo, E onSamgangbyeo, and I on Miryang 63 were increased their population densities remarkably in next generation. Dongjinbyeo infested by A$\sim$I, and Myryang 63 infested by I were hopperburned at 60 days after infestation and had a damage rating of 0.9. But Samgangbyeo infested by E was no hopperburn(damage rating: 7.3) though it showed high BPH population at 60 days after infestation.

• The Korean Journal of Food & Health Convergence
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• v.5 no.1
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• pp.33-38
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• 2019

The purpose of previous study centered around introducing minerals into bee colonies was to observe the Varrosa destructor mites-repelling effect of minerals ("Pszczelarstwo" 6/2016). The results of research published so far confirmed the purpose of using minerals in the fight against Varrosa infestation. This publication presents partial results of the next stage of research. Using foundation enriched with studied minerals in right proportions leads to diminishing the number of Varroa destructor parasites in bee colonies. It may also contribute to increase in the amount of honey obtained from bees. Foundations with minerals were in most cases correctly filled with larvae, and the new generation of bees didn't show any morphometric or physical-motor aberrations. The effect of minerals in the foundation weakens with time, which requires adequate reaction from the beekeeper. The study showed no negative effect of mineral suspensions added directly to royal jelly of larvae in the swarm cells and worker cells on the development of bees. Additional research was carried out in August and September and led to surprising observations, which are still too early to report. It obliges us to carry out further, extended subject research on a large number of bee colonies in 2017.

• Korean journal of applied entomology
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• v.55 no.2
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• pp.139-148
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• 2016

A seasonal outlook for crop insect pests is most valuable when it provides accurate information for timely management decisions. In this study, we investigated probable tele-connections between climatic phenomena and pest infestations in Korea using a statistical method. A rice insect pest, brown planthopper (BPH), was selected because of its migration characteristics, which fits well with the concept of our statistical modelling - utilizing a long-term, multi-regional influence of selected climatic phenomena to predict a dominant biological event at certain time and place. Variables of the seasonal climate forecast from 10 climate models were used as a predictor, and annual infestation area for BPH as a predictand in the statistical analyses. The Moving Window Regression model showed high correlation between the national infestation trends of BPH in South Korea and selected tempo-spatial climatic variables along with its sequential migration path. Overall, the statistical models developed in this study showed a promising predictability for BPH infestation in Korea, although the dynamical relationships between the infestation and selected climatic phenomena need to be further elucidated.

• Parasites, Hosts and Diseases
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• v.22 no.1
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• pp.78-84
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• 1984

In order to determine the infestation patterns for metacercaria of digenetic trematodes, several kinds of fresh-water and brackish-water fish were caught in River Hyungsan, Kyungpook Province, Korea and examined from March to October in 1983. They were collected by netting, fishing with rod and line, or using the bait of crushed oil cake in transparent plastic bowls, and were dissected into the flesh, scales and 6ns with tail, and then examined for the presence and infestation density of larval trematodes. Of the 11 kinds of fish examined, the encysted larvae of Exorchis oviformis were found all of them, Metagonimus yokogawai from 9 kinds, Cyathocotyle orientalis, Metacercaria hasegawai and Metorchis orientalis from 6 kinds, alld Clonorchis sinensis from 4 Kinds in the present study. In the intensity of infestation with Clonorchis sinensis, the Korean shiner, Gnathopogon atromaculatus Nichols et Pope, was the most heavily infected species, the average number of metacercariae per grata of fish flesh being 45.5, followed by the striped shiner, Puntungia hirxi Ibersenstein 11.6, and Southern top-Inouthed minnow, Pseudorasbora larva (Temminck et Shlegel) , 9.7. The intensity of infestation with the iwetagonimus larvae in 8 species of fresh-water fish was relatively low, and the average number per gram of flesh varied from 0.23 to 9.1. In comparison, the brackish-water fish were more heavily infected and the mean number of cysts per gram of flesh in the sweetfish, Plecoglossus altiwelis, was 32.9. The results of this study generally indicate that Clonorchis sinensis and Metagcnimus yckogawai infection may occur by consuming raw fresh-water fish caught in the river Hyungpook, Kyungpook Province, Korea.

• Journal of agricultural medicine and community health
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• v.3 no.1
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• pp.18-26
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• 1978

Enterobius vermicularis (pinworm) infestation in present day Korea has become one of nationwide problems. But, the incidence of pinworm infestation having been reported by many workers was almostly the data for specific groups. The incidence of pinworm infestation for 208 families of 760(male; 30, female;420) middle class inhabitant of Seoul, 238 subrural inhabitants in Gyeonggi Province and 150(male;77, female;73) rural primary students in three different districts were examined by modified Gralam's scotch-tape swab method. The results are summarized as follows; 1. The incidence of nationwide infestation a. The nationwide incidence of pinworm infestation of the 1,148 specimens examined was 28.7% (male; 27.5%, female; 29.6%). b. The highest incidence was found among 5-14 years of age. c. In comparison of the incidence by the area, the highest incidence was found among subrural area, next among rural area and the lowest among urban area. 2, Urban area a. The incidence of the 760 inhabitants examined was 23.2% (male; 24.1%, female; 22. 3%). b. The incidence of the parents group was 12.2% and children group was 30. 30.3%. c. In the parents who hold one or more pinworm poitive cases among children, the incidence of father group was 13.2% and mother group was 29.7%.3. Subrural area a. The incidence of the 238 inhabitants examined was 42.9% (male, 40.8%, female; 44.4%). b. The cumulative positive rate of anal swabs showed increasing tendency. c. Worm collection rates after chemotherapy of 98 inhabitants were 54, 0%. d. In scotch tape anal swab only one times, diagnostic value was 74.0%. e. Mother group infested with pinworm seemed to play an important role for the high incidence in individual family. f. In comparison of the incidence by the examination method, the highest incidence was found among scotch tape method. 4. Rural area The incidence of the 150 primary students examined was 34. 5% (male ; 24. 7%, female; 43.8%).