• Title/Summary/Keyword: Winter host

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The Colonizing Routes of Aphis gossypii (Hemiptera: Aphididae) to Mandarine Citrus Trees Grown in a Non-heating Plastic-film House During the Early Season (무가온 시설재배 감귤에서 계절초기 목화진딧물 개체군의 정착경로에 관한 연구)

  • Kim, Tae Ok;Kwon, Soon Hwa;Park, Jeong Hoon;Oh, Sung Oh;Hyun, Seung Young;Kim, Doog-Soon
    • Korean journal of applied entomology
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    • v.54 no.3
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    • pp.247-255
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    • 2015
  • The cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae) infests citrus orchards, causing sooty mold damage to the fruits. This study was conducted to investigate the colonizing route of A. gossypii in citrus orchards in a non-heating plastic-film house during the early season. The overwintering eggs of the aphids are frequently found on summer shoots of the citrus trees. The eggs were mostly those of Aphis citricola, without any A. gossypii when hatched. The colonization of citrus trees by alate A. gossypii in non-heating plastic-film houses was mainly observed twice, with advanced flight in late April and delayed flight in late May. The delayed flight was synchronized with the timing of the emergence of alate A. gossypii from the fundatrix generation in the holocyclic life cycle. During advanced flight in closed citrus orchards, alate A. gossypii were caught in yellow water traps installed in the fields, and the populations were found to originate from the surviving populations of the anholocyclic life cycle. Consequently, we concluded that citrus tree colonization with A. gossypii occurred during the advanced flight of the anholocyclic and the delayed flight of the holocyclic life cycle.

Research on Development Strategy of China Ice-Snow Sports Tourism Industry Based on SWOT-AHP Model-Case Study on Zhangjiakou

  • Chen, Wenjie;Zhou, Pan;Bae, Kihyung
    • International Journal of Contents
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    • v.16 no.2
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    • pp.92-101
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    • 2020
  • Industrial integration is the innovative embodiment of regional economic theory. The promotion of industrial integration is conducive to improving the scale effect and spillover effect of the industry. Also, it has the power to radiate, drive, and lead the innovation and development of the whole industrial cluster. The purpose of this paper was to identify the most suitable development pattern of the ice-snow sports tourism industry in Zhangjiakou, one of the host cities of the 2022 Winter Olympics. This study combs the characteristics of the development of the ice-snow sports industry, and analyzes the current situation of the industry in Zhangjiakou based on the SWOT-AHP method. This paper argues that the integrated industry is the most suitable development pattern for the promotion of the ice-snow culture industry in Zhangjiakou. The following content will present effective countermeasures to accelerate the development of the ice-snow culture industry integration in Zhangjiakou from three aspects: industrial resource integration, industrial chain layout, and scientific and technological innovation. The IT live simulation technique facilitates identifying some vital elements during the data collection.

Aggressiveness of Three Snow Mold Fungi on Creeping Bentgrass Cultivars under Controlled Environment Conditions

  • Chang, Seog-Won;Jung, Geun-Hwa
    • The Plant Pathology Journal
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    • v.25 no.1
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    • pp.6-12
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    • 2009
  • Snow molds are the most important winter diseases of turfgrass in the United States and Canada. Eight isolates of three snow mold fungal species (three isolates of Typhula ishikariensis, three of T. incarnata, and two of Microdochium nivale) were collected from infected turfgrasses on golf courses. The isolates were evaluated for their relative aggressiveness on three cultivars (L-93, Penncross, and Providence) of creeping bentgrass (Agrostis palustris) under the same controlled conditions. Four plant ages (15, 19, 23 and 27 week-old plants from germination to inoculation) were evaluated for their susceptibility to the three pathogens and for the recovery of the plants. Regardless of age or cultivar of the host plant, M. nivale was found to be more aggressive and faster to infect and colonize than Typhula species. After three weeks recovery, M. nivale-inoculated plants showed higher disease severity than plants inoculated with the two Typhula species. Plants infected by Typhula species displayed no significant difference in disease severity. As creeping bentgrass plants get older, the severity of disease caused by three snow molds gradually decreases. This effect was observed in all cultivars tested, suggesting expression of age-related resistance as the bentgrass plants matured.

Seasonal Variation of Infection by Three Species of Symbiotic Copepods in Clam, Tresus keenae (왕우럭에 공생하는 요각류 3종에 대한 감염률의 계절 변동)

  • Moon, Seong-Yong;Rha, Sung-Ju;Yoon, Ho-Seop;Choi, Sang-Duk
    • Journal of Aquaculture
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    • v.19 no.4
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    • pp.236-241
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    • 2006
  • Seasonal variation of the infection by three species of symbiotic copepods in clam, Tresus keenae was investigated in south coast of Korea. The prevalence and abundance of three symbiotic copepods showed seasonal variation with a peak in winter. Reproduction of the copepods occurs from early autumn to spring as indicated by higher ratio of gravid copepods. The frequency distribution of Lichomolgus inflatus, Pseudomyicola spinosus and Anthessius progectus in their host population could be fitted with negative binominal distribution. Results from the present study suggest that seasonal fluctuation in prevalence, relative density and mean intensity is related to temperature and life history of the symbiotic copepods.

The Color Characteristics and Image of the Olympic Host Country's Uniforms (올림픽 개최국가 유니폼의 색채 특성과 이미지)

  • Lim, Songmi;Lee, Misuk
    • Journal of Fashion Business
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    • v.20 no.1
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    • pp.115-126
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    • 2016
  • Today the Olympics are considered representative of a culture that symbolizes the country's image and cultural specificity, and important colors act as effective means of Olympics marketing. Each color is unique to the natural environment and cultural heritage is one of the languages of each country, region or community and it symbolizes. Hence, the purpose of this study was to examine the color and to view the color image displayed on Olympic uniforms based on the national color sensibility. After analyzing the color image of the Olympic athletes, including six kinds of uniforms and operational personnel, a cool casual/casual image is created more frequently, followed by a modern, gorgeous, dynamic, elegant/chic, dandy/classic image. The uniform color is consistent with the national image and the theme of the Pyeongchang Olympics is to enhance the country's competitiveness by widely promoting the national image of Korea around the world. Furthermore, it is necessary to provide the empirical basis for creating the 2018 Pyeongchang Winter Olympic uniforms.

Bionomics of Coleophora obducia (Lepidoptera: Coleophoridae) (잎갈나무통나방의 생활사)

  • 신상철;채정석;최광식;박일권;김철수
    • Korean journal of applied entomology
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    • v.42 no.2
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    • pp.169-171
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    • 2003
  • The life history and natural enemies of Coleophora obducia Meyrick which is a defoliating pest of Larix leptolepis were studied mainly in Chungchongbuk Province. Larix leptoiepis was the only host plant of this pest. Coleophora obducia had one generation per you and the adults emerged from mid May to late May with a peak emergence around May 14th. The mean number of eggs in an ovary was 44.5 and most females oviposited one egg on each needle. The duration of the egg stage was about two weeks. Larvae passed the winter in a pouch made by spinning the needles. Pupation began in the late April, and the pupal period was two weeks on average. The natural enemies observed were parasitoids and predators.

Hard rock TBM project in Eastern Korea

  • Jee, Warren W.
    • Proceedings of the Korean Society for Rock Mechanics Conference
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    • 2008.10a
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    • pp.33-41
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    • 2008
  • The longest tunnel has been halted at Daekwanryung by the failure of the host country of the Winter Olympiad in 2014, but modern High-Power TBM will come to Korea to excavate these long tunnels to establish the better horizontal connection between the western and eastern countries to improve the strong powerful logistic strategy of Korean peninsula. Train operation provides a key function of air movements in a long underground tunnel, and heat generation from transit vehicles may account of the most heat release to the ventilation and emergency systems. This paper indicates the optimal fire suppress services and safety provision for the long railway tunnel which is designed twin tunnel with length 22km in Gangwon province of Korea. The design of the fire-fighting systems and emergency were prepared by the operation of the famous long-railway tunnels as well as the severe lessons from the real fires in domestic and overseas experiences. Designers should concentrate the optimal solution for passenger's safety at the emergency state when tunnel fires, train crush accidents, derailment, and etc. The optimal fire-extinguishing facilities for long railway tunnels are presented for better safety of the comfortable operation in this hard rock tunnel of eastern mountains side of Korea. Since year 1900, hard rock tunnel construction has been launched for railway tunnels in Korea, tunnels have been built for various purposes not only for infrastructure tunnels including roadway, railway, subway, and but also for water and power supply, for deposit food, waste, and oils etc. Most favorable railway tunnel system was discussed in details; twin tunnels, distance of cross passage, ventilation systems, for the comfortable train operations in the future.

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Wheat Blast in Bangladesh: The Current Situation and Future Impacts

  • Islam, M. Tofazzal;Kim, Kwang-Hyung;Choi, Jaehyuk
    • The Plant Pathology Journal
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    • v.35 no.1
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    • pp.1-10
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    • 2019
  • Wheat blast occurred in Bangladesh for the first time in Asia in 2016. It is caused by a fungal pathogen, Magnaporthe oryzae Triticum (MoT) pathotype. In this review, we focused on the current status of the wheat blast in regard to host, pathogen, and environment. Despite the many efforts to control the disease, it expanded to neighboring regions including India, the world's second largest wheat producer. However, the disease occurrence has definitely decreased in quantity, because of many farmers chose to grow alternate crops according to the government's directions. Bangladesh government planned to introduce blast resistant cultivars but knowledges about genetics of resistance is limited. The genome analyses of the pathogen population revealed that the isolates caused wheat blast in Bangladesh are genetically close to a South American lineage of Magnaporthe oryzae. Understanding the genomes of virulent strains would be important to find target resistance genes for wheat breeding. Although the drier winter weather in Bangladesh was not favorable for development of wheat blast before, recent global warming and climate change are posing an increasing risk of disease development. Bangladesh outbreak in 2016 was likely to be facilitated by an extraordinary warm and humid weather in the affected districts before the harvest season. Coordinated international collaboration and steady financial supports are needed to mitigate the fearsome wheat blast in South Asia before it becomes a catastrophe.

Some Aspects of Population Dynamics of Rice Leafhoppers in Korea (한국에 있어서 벼멸구$\cdot$매미충의 개체군동태에 관하여)

  • Hokyo Nobuhiko;Lee Moon Hong;Park Joong Soo
    • Korean journal of applied entomology
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    • v.15 no.3 s.28
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    • pp.111-126
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    • 1976
  • Regional differences in economic importance of the four species of rice leafhoppers, viz., Laodelphax striatellus, Nephotettix cincticeps, Nilaparvata Iugens and Sogatella furcifera, were analyzed and discussed based on population surveys conducted in Suweon and in southern and south-western coastal areas. The economic importance of L. striatellus and N. cincticeps, which are found throughout the year in Korea, seems to be less in middle regions. This is believed due to effective natural control through severe winter climate, cultural practices in rice and barley growing, and natural enemies such as spiders. However, the economic importance of these two species is significantly greater in southern regions with a less severe winter climate, and where cultural practices in rice and barley favour synchronization between the life cycles of insects and the seasonal succession of host plants. with regard to N. lugens and S. furcifera, which cannot overwinter in Korea, initial populations are the result of long distance migration across the East China Sea. Weather elements related to their migration result in more abundant immigrants of these two species in southern than in middle regions. Thus, different policies are needed for the integrated control of rice leafhoppers in middle and southern Korea.

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Viruliferous Rate of the Small Brown Planthopper in the Maize Field Infected with Rice black-streaked dwarf virus (옥수수 재배지의 벼검은줄오갈병 매개충인 애멸구의 보독충율)

  • Lee, Bong-Choon;Jung, Ji-Hun;Kim, Jung-In;Yoon, Young-Nam;Hong, Sung-Jun;Kwak, Do-Yeon;Hong, Yeon-Kyu;Kang, Hwang-Won;Lee, Key-Woon
    • Research in Plant Disease
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    • v.14 no.3
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    • pp.226-228
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    • 2008
  • The Rice black-streaked dwarf virus (RBSDV) infected 99-100% of a $1000\;m^2$-maize field in Mungyeong City in 2007. Adjacent to the area is a Persimmon orchard where barley crops were grown under the trees as green manure crops and for soil amendments. The barley acted as winter host to the small brown plant hoppers (SBPH) enabling the insects to survive and pass the winter season. The existence of RBSDV was detected and confirmed by RT-PCR using S9 specific primer. Samples of the insect vector SBPH were collected in the area on May 3, June 7 and, August 4 and the results of the RT-PCR analysis revealed viruliferous insect rates of 2.9, 4.8, and 4.4%, respectively. These observed viruliferous insect rates were similar with those detected in RBSDV infected rice fields.