Journal of Agricultural Meteorology
Online ISSN : 1881-0136
Print ISSN : 0021-8588
ISSN-L : 0021-8588
Volume 29, Issue 4
Displaying 1-3 of 3 articles from this issue
  • The relation between light quality and photosynthesis of leaves irradiated from both sides
    Bak KO, Kazutoshi YABUKI
    1974 Volume 29 Issue 4 Pages 229-237
    Published: March 09, 1974
    Released on J-STAGE: February 25, 2010
    JOURNAL FREE ACCESS
    It was proved in the proceding paper that the action spectrum of photosynthesis in the leaf of higher plants differs with absorbing rate of each light of different wave length, assuming that the structure within the leaf was uniform.
    From the viewpoint of optical and anatomical characteristics, the present paper discusses the dependence of the difference in the mesophyll structure on the action spectrum of photosynthesis by investigating each photosynthetic rate of leaves irradiated by red, green and blue light from adaxial side and both sides. Five plants, cabbage, Swiss chard, cucumber, kidney bean, and lettuce, were provided as materials. The results obtained were as follows:
    1) The photosynthetic rates of Swiss chard, cabbage and lettuce, when irradiated by red or blue light from both sides, were much more than those obtained under the irradiation from adaxial side.
    2) The photosynthetic rate of cucumber, when irradiated by red light from either adaxial side or both sides, was the same as that under blue light. The photosynthetic rate in green light was less for both sides than adaxial side.
    3) In all cases, the photosynthetic rate of kidney bean when irradiated from adaxial side was much more than that for irradiation from both sides.
    4) The efficiency of absorbed light in red and blue light depended on the variety of plants in the same way as the photosythetic rate. In green light, however, the efficiency was equal in all leaves whether irradiated from adaxial side or both sides.
    5) The leaves of cabbage, Swiss chard, and lettuce had the uniform mesophyll layers. The leaves of cucumber and kidney bean had the palisade and the spongy tissue layers.
    6) The transmission spectra of thin layers were the same anywhere within the mesophyll layer in the leaf of Swiss chard. But the transmission of thin layers within the palisade and the spongy tissue was not exactly alike in the léaves of cucumber and kidney bean. It was higher in the spongy tissue layer than in the palisade layer. The difference between these two layers increased at the wave length which gives lower transmission.
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  • Toyoki KOZAI
    1974 Volume 29 Issue 4 Pages 239-247
    Published: March 09, 1974
    Released on J-STAGE: February 25, 2010
    JOURNAL FREE ACCESS
    In the preceding paper (Kozai 1973), an analytical method has been developed for calculating the distribution of direct solar irradiation in an isolated single-span greenhouse glazed with flat glass as a function of house dimensions, house orientation, latitude of greenhouse site, time of year, and the mean radiation characteristics of the greenhouse site. In this paper, it is clearly shown that the proportion of the area of a greenhouse surface that may be regarded as freely transmitting sunlight varies widely with the shape of a structural frame and geometrical position of the sun relative to the frame.
    Applications of the model to various greenhouses are described in this paper. In this analysis no consideration was given to internal reflection. The model considered the effect has already been described in the other paper (Kozai 1972b).
    Some of the results computed for the winter months for the greenhouses whose shapes and dimensions are given in Fig. 1 and Table 1 are as follows:
    1. The transmissivity of the greenhouse covered with only horizontal structural elements for direct solar light is not largely decreased with the increase of the depth of the structural elements. However, the horizontal structural elements running E-W directionin the south roof and wall cause a nonuniform space distribution of the daily integrated direct solar light in a greenhouse.
    2. The transmissivity of a N-S house for direct solar light is sharply decreased with the increase of the depth of the glazing bars.
    3. The space average transmissivity of the NW-SE house for direct solar light is decreased to about 42% at around 9:30 in winter.
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  • 1974 Volume 29 Issue 4 Pages 248
    Published: March 09, 1974
    Released on J-STAGE: February 25, 2010
    JOURNAL FREE ACCESS
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