• Title/Summary/Keyword: vinyl house(plastic film houses)

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Ultraviolet Wave Length Effective in the Sporulation of Didymella bryoniae, a Gummy Stem Blight Fungus in Cucurbits, and the Disease Control Effect by the Use of Ultraviolet Light-Absorbing Vinyl Film (박과작물 덩굴마름병권 Didymella bryoniae의 포자형성 유효 자외파장과 자외선 흡수필름을 이용한 병 방제효과)

  • 권미경;홍정래;기운계;조백호;김기청
    • Plant Disease and Agriculture
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    • v.5 no.1
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    • pp.20-26
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    • 1999
  • Ultraviolet light is required for the sporulation of Didymella bryoniae, a gummy stem blight fungus in cucurbits such as watermelon, melon, oriental melon, cucumber and pumpkin. In this experiment, the upper limit of wave length for the production of pycnidia of D. bryoniae was 365 nm - 375 nm. Two plastic houses were covered with either common transparent film (wave length longer than 225 nm is transmitted) or UV-absorbing film ( wave lenght shorter than 388 nm is absorbed). In both houses, seedlings inoculated with D. bryoniae were placed in the center of the house at 30 days after transplantation of watermelon (cv. Whanhoseong), and the disease incidences between the houses were compared until 80 days after transplantation. The number of disease lesions and incidence of pycnidia-producing lesions under the UV-absorbing film were reduced by 90% and 80%, respectively, compared to the common transparent film. The internode lengths of plants grown in the two houses were not significantly different, but the plants grown under the UV-absorbing film had longer vines and more leaves than plants under the common transparent film. However, fruit characters such as weight, length, width, rind thick and brix, were not different between the two houses. Occurrence of aphids was reduced in the UV-absorbing film, but those of mites or diseases (powdery mildew and sooty mold) were not different between the houses. These results suggest that disease incidence of gummy stem blight of watermelon in the greenhouse can be controlled by the use of UV-absorbing film.

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A Study on Experiments the Environmental Conditions and the Adaptation of the Human Body in the Vinyl House (Vinyl House 내의 환경조건과 인체적응에 관한 실험연구)

  • Shim, Bu-Ja
    • Journal of Preventive Medicine and Public Health
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    • v.27 no.1 s.45
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    • pp.59-73
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    • 1994
  • The purpose of this study is to experiments the environmental conditions and the adaption of the human body in the vinyl house. The study was done in spring and winter and experimental clothes were used working clothes in the vinyl house. The results are as follows. 1. Environmental Conditions In the spring season, the indoor air temperature was $27.4{\pm}3.7^{\circ}C$ and the outdoor air temperature was $14.4{\pm}2.7^{\circ}C$. In the winter season, the indoor air temperature was $18.3{\pm}4.8^{\circ}C$ and the outdoor air temperature was $7.6{\pm}2.5^{\circ}C$ on the average. 2. Skin Temperature In the spring season, the mean skin temperatures indoor and outdoor were $33.81{\pm}0.7^{\circ}C\;and\;31.57{\pm}0.8^{\circ}C$ respectively, a difference of $2.24^{\circ}C$. In the winter season, they were $31.95{\pm}1.93^{\circ}C\;and\;29.86{\pm}0.55^{\circ}C$ respectively, a difference of $2.09^{\circ}C$. 3. Clothing Climate In the spring season, the temperature and humidity in the inner layer of clothing were $34.77{\pm}0.80^{\circ}C\;and\;70.75{\pm}1.65%$ indoor, $31.9{\pm}0.52^{\circ}C\;and\;51.9{\pm}3.70%$ outdoor respectively. In the winter season, those were $32.52{\pm}1.04^{\circ}C\;and\;64.65{\pm}3.68%$ indoor, $30.27{\pm}0.96^{\circ}C\;and\;45.07{\pm}2.68%$ outdoor respectively. 4. Physiological Factors Body temperature increased slightly and the pulse rate also rises, but blood pressure decreased a little with the rise of environmental temperature both in the spring and winter seasons. 5. Psychological Factors Thermal sensation in the spring season was expressed as 'slightly warm' or 'warm' indoor and as 'neutral' in the open air, while in the winter it was expressed as 'neutral' or 'slightly warm' outdoor the house and as 'cold' in the open air. Comfort sensation was characterized as 'uncomfortable' or 'slightly uncomfortable' indoor both in the spring and winter seasons, but in the open air it was characterized as 'comfortable' in the spring and as 'slightly uncomfortable' in the winter.

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