• Korean journal of applied entomology
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• v.56 no.2
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• pp.121-133
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• 2017

This study was conducted to investigate the community structure of arthropods, including various insect pests and their natural enemies, in walnut orchards. Furthermore, we tried to compare the species richness and community structure of arthropods by three different sampling methods, including beating, funnel trap, and pitfall trap. Arthropods were surveyed in three walnut orchards located at Gimcheon, Buyeo, and Hwaseong in South Korea from May to September, 2016. A total of 408 arthropod species were identified from 4,372 individuals, and 63 species were collected in all study sites. The species richness was the highest in funnel trap, while the abundance was the highest in pitfall trap. The species composition of the insects collected by the beating method was more similar to that of the funnel trap than the pitfall trap. Although the distributions of the economically important pests were different according to the study sites, six species, including Dichocrocis punctiferalis, Pseudaulacaspis pentagona, Gastrolina depressa, Lycorma delicatula, Metcalfa pruinosa, and Pochazia shantungensis, are the potentially important pests in walnut orchards. We also found a variety of predators and parasitoids, which will be important for walnut pest management.

• The Korean Journal of Ecology
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• v.28 no.5
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• pp.287-293
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• 2005

This study was conducted to evaluate the effect of the conventional pesticide application system on the rice spider community based on the quantitative investigation of arthropod community in the rice fields in Saran area, Hwasung-si, Kyeonggi-do from 1996 to 1998. Spiders were the highest dominant group comprising over 90% of all natural enemies in their density, and showed very stable yearly occurrence. In these fiekds the mean density of spiders was about 10 individuals/$0.25m^2$ during the rice growing season, and three families including Lycosidae, Tetragnathidae and Linyphiidae were very abundant. The colonization of spiders occurred in early season and they showed rapid density increase in mid-season. They maintained the highest density to the late season and their density decreased at harvest season. In the years of the low rice pest occurrence, the disturbance effect on spider community by pesticides were less. Two dominant species, Pirata subpiraticus and Pachygnatha clerki, had different population dynamics; Pirata subpiraticus showed the rapid density increase in the mid-July, and most of them remained immature stages, however, in the case of Pachygnaths clerki population, they rapidly increased in the late August and most of them remained adult stage during the late growing season.

• Korean journal of applied entomology
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• v.51 no.2
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• pp.83-90
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• 2012

The effect of natural enemies on four major pests of hot pepper was tested in greenhouses. The aphids were successfully controlled by introducing three Aphidius colemani-banker plants, and releasing 23.3 wasps per $m^2$ on April 16 and 23 wasps per $m^2$ in a greenhouse of 660 $m^2$. To control thrips, Orius laevigatus was released twice, 3.0 bugs per $m^2$ at a time(May $11^{th}$ and June $12^{th}$). The thrips population was controlled within 0.3 thrips per flower during the growing season. To control two species of mites, Tetranychus kanzawai and Polyphagotarsonemus latus, and the silverleaf whitefly, Bemisia tabaci, a total of 113.7 individuals of Amblyseius swirskii were released twice(May $11^{th}$ and $30^{th}$). The densities of B. tabaci and T. kanzawai were kept within 171.0 individuals/trap and 0.8 individual/leaf, respectively. P. latus was suppressed completely twelve days after release. The cost of the released natural enemies to control the four arthropod pests in this study was 420,000 Won per 660 $m^2$.

• Parasites, Hosts and Diseases
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• v.48 no.2
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• pp.145-149
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• 2010

Medically important arthropods, including fleas, play an important role in causing clinical disorders and disease in man and domestic animals. This study was conducted to determine the seasonal flea infestations for domestic dogs from different geographic regions of Iran. A total of 407 fleas, belonging to 5 different species, were recovered from 83 domestic dogs from 3 regions. There was a distinctive pattern of species distribution and infestations with the highest infestation rates observed in a temperate climate and higher rainfall. Additionally, fleas were observed over all seasons, except February and March, with the highest infestation rate observed in August (24.7%) and the lowest rate in January (1.7%). They also parasitize dogs with a different spectrum of species. The cat flea, Ctenocephalides felis (67.5%), exhibited the highest prevalence among all flea species found on dogs. Thus, climatic conditions and seasonal patterns impact on flea infestation and must be considered in developing control programs.

• Korean Journal of Veterinary Research
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• v.48 no.1
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• pp.61-66
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• 2008

Akabane disease is caused by an arthropod-borne viral pathogen and leads to congenital abnormalities of the central nervous system in infected ruminants. One isolate, KV0505, showed cytopathic effect in Vero cells. The KV0505 isolate was obtained from plasma, which was collected from a cattle raised on Jeju Island in May 2005. Jeju Island is located near the southern part of the Korean peninsula. The isolate was confirmed as Akabane virus (AKAV) by immunofluorescence assay using AKAV specific monoclonal antibodies and reverse transcription polymerase chain reaction (RTPCR). Suckling mice inoculated with the isolate showed signs of paralysis and died within 10 days postinoculation. Comparisons of the KV0505 N gene sequence with 39 other known AKAV strains revealed nucleotide homologies ranging from 83.6% (MP496 strain) to 99.7% (M171 strain). When compared with the K-9 strain, which was isolated from a cow in Korea in 1994, the nucleotide sequence homology with the N gene was 99.7%. Thus, genes of the KV0505 isolate were closely related to those of the M171 strain, which were clustered into the Ic group of AKAV.

• Journal of Fisheries and Marine Sciences Education
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• v.15 no.2
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• pp.135-144
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• 2003

1. The appearance of fisheries animals and plants of investigation areas were fishes, 20 species; algae, 9 species; molluska, 6 species; arthropod, 12 species; echinoderm, 5 species by confirmed appearance species. 2. The C.P.U.E by trap(1pcs of trap) were 3.95 species and weight of 2,098g, mainly catching species are greenling and jacopever(94.16%). The C.P.U.E by long liner(long liner 1coil, 100pcs) were 11.7species and weight of 6,418g, It occupied jacopever(35.63%) greenling(20.78%), bastard halibut(20.31%). The C.P.U.E of appearance species gill net(ipcs of gill net) were 5.05species and weight of 3,050g, It occupied jacopever(39.63%) greenling(29.83%), bastard halibut(17.47%). 3. The results of comparative analysis and natural species and stocked species, in case of bastard halibut, jacopever species were occupied species(83.33~92%), weight(86.86~96%). The stocked species were occupied species of 8.00~16.67%, weight of 4.00~13.14%. Provided the stocked projets were enacted effectively in future. The density of dwelling of stocked species were increase. Also, it will be contribute to the increase of fishermens income.

• Korean Journal of Microbiology
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• v.11 no.3
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• pp.134-151
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• 1973

The physico-chemical and biological factors of coastal sea water were measured bimonthly from 1976 to 1979 for elucidating the relationship between microbial distribution and environmental factors at Masan and Jinhae bay. The experimental results are summarized as followings : 1) The polulation size of bactriz in sea water were increasing as the water temperature increased, and that was higher at station 2 and 3 than at station 1. The number of fungi showed the highest value on July on bottom. The population size of yeast showed no seasonal variation and also showed a relation with the geographic distance. 2) The correlationship between microbial distribution and environmental factors showed little coefficiency in surface water. And the other hand, at bottom water, between general bacteria and water temperature and dissolved oxygen, and between yeast and salinity, there were relatively high coefficiecy.

• Journal of Korean Society of Forest Science
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• v.72 no.1
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• pp.1-8
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• 1986

This study was carried out to classify the arthropods inhabited in pine mushroom (Tricholoma matsutake Singer). The arthropods were collected in a state forest (196 compartment, 157ha) located in Yangyang-gun, Kangwon-do. After collection the arthropods were classified in laboratory. The results obtained are summarized as follow; 1. Insects inhabited in pine mushroom are in total 19 Families of 7 Orders. Some animals in Araneina, Acarina, Nematoda and Stylommatophora were also observed, 2. The most injurious pests are Gyrophaena niponensis, Elateridae, Deosophilidae and Philomycidae (Stylommatophora). 3. The most dominant species is Gyrophaena niponensis (Staphylinidae, Coleoptera). 4. Some possible natural enemies are Oxyporus germanus, Sphedanolestes impressicollis, Phoridae, Carabidae, Pteromalidae, Eulophidae and Araneina.

• Journal of Forest and Environmental Science
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• v.35 no.3
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• pp.189-196
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• 2019

Plants are consumed by a myriad of organisms that compete for resources. Direct interactions among multiple plant-feeding organisms in a single host can range for each species from positive to negative. Wood-boring beetle faces a number of biotic and abiotic constraints that interfere with the good prospects from the tree. Biotic factors, including arthropod pests and diseases, and abiotic factors, such as drought and water-logging, are the major constraints affecting the species. The present study aimed to provide basic data for analyzing forest health, identify the kinds of wood-boring beetles in the central part of Korea. Our second goal was to analyze the species composition and diversity of regional communities and to examine. A total of 10,461 individual wood-boring beetles belonging to 8 families and 50 species attracted to trap trees in the pine forests were recorded during the study period on study sites. The results of the analysis of collected species showed that the community structure on all study sites was similar. Seasonal occurrences of dominant wood-boring beetles (5 species) from each study site showed the highest number of all species, except for Siphalinus gigas in May, followed by a gradual decline, and the largest number of Siphalinus gigas appeared in June. The similarity index of species composition was relatively high, ranging from 0.75 to 0.90 for each study site.

• Journal of the Korean Wood Science and Technology
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• v.47 no.3
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• pp.371-380
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• 2019

Termites are pests that cause serious economic and cultural damage by digesting wood cellulose. Termites are arthropods and have an epidermis surrounded by a chitin layer. To maintain a healthy epidermis, termites have chitinase (${\beta}$-1,4-poly-N-acetyl glucosamidinase, EC 3.2.1.14), an enzyme that hydrolyzes the ${\beta}$-1,4 bond of chitin. In this study, the amino acid sequence of the gene, which is presumed to be termite chitinolytic enzyme (NCBI accession no. KC477099), was obtained from a transcriptomic analysis of Reticulitermes speratus KMT001 in Bukhan Mountain, Korea. An NCBI protein BLAST search confirmed that the protein is a glycoside hydrolase family 18 (GH18). The highest homology value found was 47%, with a chitinase from Araneus ventricosus. Phylogenetic analysis indicated that the KC477099 protein has the same origins as those of arthropods but has a very low similarity with other arthropod chitinases, resulting in separation at an early stage of evolution. The KC477099 protein contains two conserved motifs, which encode the general enzymatic characteristics of the GH18 group. The amino acid sequences $Asp^{156}-Trp^{157}-Glu^{158}$, which play an important role in the enzymatic activity of the GH18 group, were also present. This study suggests that the termite KC477099 protein is a new type of chitinase, which is evolutionarily distant from other insect chitinases.