• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.4
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• pp.938-945
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• 2004

On the relationship between the red tide occurrence and the oceanographic factors in the middle coastal area in the South Sea of Korea, the favorable oceanographic conditions for the red tide formation are considered as follows； the calm weather increases sea water temperature in summer and early-fall which the red tide occurs frequently, and the heavy precipitation brings some riverine water to ween: low salinity, high suspended solid, low phosphorus and high nitrogen, respectively. We decided the potential areas in the coastal zones vulnerable to the red tide occurrence based on the limited factors controlling the growth of phytoplankton. By using GIS through the overlap for three subject figures (phosphorus, nitrogen and suspended solids), it was founded that the potential areas are the Yeosu∼Dolsan coast, the Gamak bay, the Namhae coast, the Narodo coast, the Goheung and Deukryang bay. This result has very well coincided to the results of the satellite and in-situ data.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.393-398
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• 2020

The blueberry gall midge, Dasineura oxycoccana (Johnson) (Diptera: Cecidomyiidae), is an emerging pest on cultivated blueberries in Korea. To develop a sensitive tool for monitoring this pest in blueberry orchards, we compared the attractiveness of host plant volatiles and sex pheromone to D. oxycoccana adults. We performed gas chromatography-mass spectrometry (GC-MS) analysis of solid-phase microextraction (SPME)-collected volatiles that were released from blueberry ('Darrow' cultivar). The analysis revealed two major volatiles, cinnamaldehyde and cinnamyl alcohol from flowers; and three major volatiles, β-caryophyllene, germacrene D, and α-farnesene from shoots and young fruits. In field tests conducted in Gunsan, Korea in 2019, commercialized cinnamaldehyde, cinnamyl alcohol, β-caryophyllene, and α-farnesene, used singly or in quaternary combination, were unattractive to the blueberry gall midge. However, traps baited with the known sex pheromone (2R,14R)-2,14-diacetoxyheptadecane attracted significantly more males than the treatments with plant volatiles or the control. No synergistic effect was observed between sex pheromone and plant volatiles. Male D. oxycoccana were captured in the pheromone traps from May to August, with three peaks in mid-May, late June, and late July in Gunsan blueberry fields in 2020.

• Korean journal of applied entomology
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• v.32 no.3
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• pp.307-316
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• 1993

The potential of using GIS in analyzing pest surveillance data was explored. The Spatial Analysis System (SPANS) was used to construct a spatial data base to study pest distributions using pest surveillance data collected from 152 stations in South Korea. The annual spatIal distributions of the striped rice borer(SRB), Chdo suppressalis, showed that high densities started to expand in the early 1980s, reaching a peak in 1988. The pattern change appears to be related to cultivation of japonica and indica-japonica hybrid varieties in South Korea. Japo7l!ca varieties have longer duration resulting in the SRB haVlng more time to mature and hibernate in wmter. The locus of SRB spread appears to be located in the mid-west region near lri, Chun~ Buk Province. High brown planthopper (BPH) populations in South Korea are often related to the early immigration and temperature. The simulated distribution of PPH densities in September using these two factors was compared with the actual distribution obtained using 1990 data. The two density maps corresponded closely excepL for differences in the south eastern valley. By overlaying the simulated map layer with the elevation and rice area maps, more specific BPH risk zones could be identified.

• Korean journal of applied entomology
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• v.59 no.2
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• pp.145-152
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• 2020

The populations of Polyphagostarsonemus latus (Acari: Tarsonemidae) peaked two times on green perilla grown in greenhouses of Geumsan-Gun, Chungchungnamdo. The first peak of P. latus was in the middle of June, after it was first detected in late May. The population of P. latus peaked for the second time in mid July as its density stared rapidly increasing in early July. The application of chemical pesticides and eco-friendly agricultural materials, the two management methods used to control P. latus on green perilla, did not alter the occurrence patterns of P. latus; population size of the mite was much larger in greenhouses using chemical pesticides than in the ones using eco-friendly agricultural materials. This difference might be cuased by continuity of the management methods. Chemical control of P. latus should be limited owing to pesticide residue. The highest density of P. latus on green perilla plants was observed after 25 days after inoculation. The density was the highest in mid-aged leaves (e.g., the largest leaves) and the lowest in newly developed leaves (e.g., smallest leaves). However, there was no significant (P > 0.05) correlation between leaf size and density of P. latus. These results indicate that leaf size (e.g., leaf age) did not affect the occurrence of P. latus. Thus, any leaf of a green perilla plant is available as a sample unit for P. latus.

• Korean journal of applied entomology
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• v.61 no.3
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• pp.481-496
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• 2022

In order to establish an effective pest control strategy, we investigated the occurrence of lepidopteran insects in the major trees growing in urban forests from 2019 to 2021. In total, we recorded 76 species of 14 families in Prunus spp., 40 species of eight families in Acer spp., 43 species of 10 families in Zelkova serrata, 28 species of seven families in Rhododendron spp., and 10 species of four families in Hibiscus syriacus. Among these, Hyphantria cunea and Lymantria dispar were recorded from all five tree taxa monitored. The most frequently occurring species in the different tree groups were as follows: H. cunea and Phalera flavescens in Prunus yedoensis, Epinotia ulmicola in Z. serrata, and Rehimena surusalis in H. syriacus. H. cunea also occurred in Rhododendron spp. and Acer spp., although the numbers were lower than those recorded in Prunus spp. and Z. serrata. Our results highlight the importance of focusing on the frequency of occurrence of lepidopteran insects in Prunus spp. and Z. serrata, whereas the presence of these insects in both Acer spp. and Rhododendron spp. Appears to be less problematic. From the perspective of reducing the risks to human health, our findings indicate that the application of pheromones for monitoring lepidopteran species and the use of mating disruptors would be desirable approaches that would contribute to minimizing the spraying of pesticides in urban forests.

• Korean journal of applied entomology
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• v.17 no.2 s.35
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• pp.105-113
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• 1978

The experiments were carried out both at $#160$, Anyang Ri, Anyang, Kyung-gi Do, as a field plot and at college of Agriculture, Seoul National University, Suweon as laboratory plot, in order to unnorive the types of traps for collection of adult pine gall midge (Thecodiplosis japonensis Uchida) And the conclusions of the experimental results were as follows. (1) The seasonal fluctuation of the adult emergence of the PGM continued from middle pa.1 of the May to late part of the August. And the peak of the adult emergence showed variation in the number of PGM captured, according to the types of traps used, such as May 2g-june 2, by standard Cage, June 3-June7 by Funnel-A t.sp and June 8-June 12 by Suction-Trap. (2) The Percentage of the emergence in the laboratory experimental Plot were $41.06\%$ of Funnel-A traps used. f 3) The Suction-Trap was considered as effective instrument of. collection of adult PGM especially in the seasons of both earlier and later parts of the adult emergence, which is the population density is extremelty low. (4) It is considered that the recommendable instruments were Funnel-A type of trap and suction-Trap according to the experimental results obtained.

• Korean journal of applied entomology
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• v.22 no.1 s.54
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• pp.21-25
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• 1983

To develop forecasting methods of rice sheath blight caused by Rhizoctonia solani, two rice cultivars Jinheung (Japonica type) and Yushin (Tongil type) were used from 1976 to 1981. Severity of rice sheath blight disease at maturing stage was estimated by top lesion height, percentage of top lesion height vs. plant height in July and lesion index on September 11. The relationship between top lesion height on July 11 and degree of damage at maturing stage for a cultivar Yushin was represented by the equation of Y=4.64x-13.2, and $r=.840^{**}$, where Y is degree of damage by shea4h blight at maturing stage and x is top lesion height on July 11. Considering the percentage of infected hills/stems was rapidly increased from July 11 to August 1, the most effective period and time for fungicide spray were considered July 15 and July 25 or July 25 and August 5.

• Korean journal of applied entomology
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• v.53 no.3
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• pp.209-215
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• 2014

This study was performed to monitor the seasonal occurrence of Pseudococcus comstocki (Kuwana) by using pheromone traps and to test a mating disruption technique to control this pest in pear orchards. We compared the attractiveness of rubber septa loaded with 1.5 and 3.0 mg of the pheromone, 2,6-dimethyl-1,5-heptadien-3-yl acetate. A total of 1,021 and 1,431 males were caught in traps baited with 1.5 mg and 3 mg of the pheromone, respectively. The numbers of males caught were not affected by trap color, although yellow traps were more attractive than white traps. In 2012, P. comstocki males were captured between June and October, with peaks in late June, early August, and late September. In 2013, the males were trapped between June and October, with peaks in middle June, late July, and late September. In pheromone mating disruption tests, catches were reduced by 17.7, 65.3, and 62.9% in orchards treated with 450, 900, and 1,350 mg per 10 a of the pheromone, respectively. At harvest, 3.4, 2.9, and 4.8% of fruits in orchards treated with 450, 900, and 1,350 mg per 10 a were damaged by P. comstocki, while 9.5% were damaged in the control orchard.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.411-416
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• 2020

Whitefly populations found in heated tomato greenhouses were monitored across three locations in Korea (Nonsan and Buyeo, Chungnam Province; Iksan, Jeonbuk Province) from November to May during the 2015 -2018 growing seasons. From May to October, surveys were conducted in Jangsu (Jeonbuk Province), where retarding cultivation was performed. Whitefly populations were classified and quantified by location and year. The dominant species were Trialeurodes vaporariorum (Westwood) and Bemisia tabaci (Gennadius). The species populations were mixed, but the frequency of occurrece of B. tabaci was higher than that of T. vaporariorum. Although whitefly populations started to increase in late March, they sharply increased in May and the highest population density was observed at the end of the harvest season. Therefore, the management of greenhouse tomato whiteflies through monitoring should begin in early March. In the case of retarding cultivation, the management of whitefly populations should be implemented in June, before the density of whitefly populations increases.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.2
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• pp.60-74
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• 2017

To facilitate prevention of highly pathogenic avian influenza (HPAI), a GIS is widely used for monitoring, investigating epidemics, managing HPAI-infected farms, and eradicating the disease. After the outbreak of foot-and-mouth disease in 2010 and 2011, the government of the Republic of Korea (ROK) established the GIS-based Korean Animal Health Integrated System (KAHIS) to avert livestock epidemics, including HPAI. However, the KAHIS is not sufficient for controlling HPAI outbreaks due to lack of responsibility in fieldwork, such as sterilization of HPAI-infected poultry farms and regions, control of infected animal movement, and implementation of an eradication strategy. An outbreak prediction model to support efficient HPAI control in the ROK is proposed here, constructed via analysis of HPAI outbreak patterns in the ROK. The results show that 82% of HPAI outbreaks occurred in Jeolla and Chungcheong Provinces. The density of poultry farms in these regions were $2.2{\pm}1.1/km^2$ and $4.2{\pm}5.6/km^2$, respectively. In addition, reared animal numbers ranged between 6,537 and 24,250 individuals in poultry farms located in HPAI outbreak regions. Following identification of poultry farms in HPAI outbreak regions, an HPAI outbreak prediction model was designed using factors such as the habitat range for migratory birds(HMB), freshwater system characteristics, and local road networks. Using these factors, poultry farms which reared 6,500-25,000 individuals were filtered and compared with number of farms actually affected by HPAI outbreaks in the ROK. The HPAI prediction model shows that 90.0% of the number of poultry farms and 54.8% of the locations of poultry farms overlapped between an actual HPAI outbreak poultry farms reported in 2014 and poultry farms estimated by HPAI outbreak prediction model in the present study. These results clearly show that the HPAI outbreak prediction model is applicable for estimating HPAI outbreak regions in ROK.