The relationship between light quality and photosynthesis or optical characteristics (transmission, reflection and absorption spectra) of leaves were measured for swisschard (Beta vulgaris L., ), cucumber (Cucumis sativus L., ) and kidney beans (Phaseolus vulgaris L., ) grown under different light qualities.
The plants were grown under lights of blue, green and red provided with colored fluorescent lamps at the intensity of 12 W m^-2 for 25-40 days in growth cabinet (Fig. 1) with 12 hr day length and a constant temperature, 25±1°C. The plants were also exposed to red light with the intensity of 24 W m^-2
In swisschard leaves with uniform mesophyll, the optical characteristics and the action spectrum of photosynthesis did not vary with light quality given to the plant during the growing period. Shape of the action spectra was similar to that obtained by Hoover. On the other hand, in cucumber and kidney bean leaves with the palisade and the spongy tissue, somewhat lower transmittance and higher absorptance were found in the leaves developed under blue light as compared to those under the other lights. However, there were no difference among their action spectra of photosynthesis. The shapes of action spectra were the intermediate type between Hoover's and Gablielsen's.
The leaves grown under stronger red light had lower transmittance and reflectance and higher absorptance than the weaker lights in the all plants. Their action spectra of photosynthesis were Gablielsen's type.
From these results, it was recognized that the effect of light quality on the optical characteristics of leaves varied with the anatomical characteristics of leaves, but the action spectrum of photosynthesis was hardly influenced with light quality in the all plants, and that there was not the phenomenon of so-called‘chromatic adaptation’ in photosynthesis of higher plants.

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Drying conditions after harvest and the form of the rice grain at different stages in the milling process affect the degree of infestation by pest insects. The reproduction and development of two rice weevils, Sitophilus zeamais and S. oryzae, were compared from life tables obtained at 30°C and 70% R.H, on rice grain at different stages in its processing (rough, hulled, or polished rice) and under different drying conditions for rough rice (nat-urally dried by hanging on racks or mechanically dried with heated air) .
No progeny were found on rough rice dried naturally. Weevils were able, however, to deposit eggs into a split in the husk of rough rice that was produced by mechanical drying. The average length of the developmental period was shortest on hulled rice, polished rice probably being inferior to hulled rice in its content of nutrients. The longevity and oviposition period of adult weevils were longest on polished rice and shortest on rough rice. The reproductive potential changed with adult aging. The peak of natality (b_x) curve came earlier on hulled rice than on polished rice. The reproductive potential during the adult life span was highest on hulled rice and smallest on rough rice.
Our results are evidence that rough rice is the most desirable form in which to store rice grain to prevent its infestation by rice weevils.

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The changes in photosynthetic rates of cucumber (Cucumis sativus L. cv. Nagaf ushinari No. 4) leaves after CO₂-enrichment were examined.
On the first day after the CO₂-enrichment (5, 000 ppm), the magnitude of increase in the photosynthesis was 2.7 times, when the photosynthetic rate under CO₂-enrichment was compared with that under atmospheric CO₂ concentration. In the afternoon of the second day, however, the decrease in photosynthetic rate was observed. In the early time of the third day, the photosynthetic rate of the same leaf exceeded the last value on the second day, but again decreased in the afternoon.
The photosynthetic rate of this leaf diminished gradually on and after the fourth day. The decrease in photosynthetic rate under CO₂-enrichment was conspicuously observed on the leaves with lower position than those with upper position. The photosynthetic rates of upper leaves were about the same as those at the beginning of CO₂-enrichment. The decrease in photosynthetic rate under CO₂-enrichment was greater when the concentration was higher and the duration of enrichment was longer. The photosynthetic rate of leaf grown under low light level considerably decreased more than that grown under high light level with the duration of CO₂-enrichment.

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A heat transfer model has been formulated for the part of a greenhouse that is above ground. The model is for heat transfer at night, and is to be used to analyze the way in which a thermal environment is formed at night during the coldest season. This environment is formed by spraying well water between the roofing layers of a double-roofed green-house. It has greatly cut heating costs and is being used in the cultivation of vegetables and flower in the Kanto District of north-central Japan.
After estimation of parameters of the model from measured values of the environmental conditions, the night temperature at various points in the green-house were calculated from the model. The average error in the estimations was about 0.2°C, which is considered accurate enough for most practical applications.
For a measured greenhouse with a well-water flow rate of 6.75 kg hr^-1 m^-2 (floor area) that used no other heating, the culture room night air temperature (from 6 p.m., 18 Jan. to 6 a.m., 19 Jan., 1981), θ_in, was expressed as θ_in=0.664 θ_so+0.145 θ_N + 0.141 θ_ou+0.050 θ_sk+0.1°C and was within the bounds of accuracy. θ_so was the surface temperature of the bed soil, θ_N the well-water temperature at the spray nozzle, θ_ou the outside air temperature, esk the equivalent sky temperature (based on the assumption that the sky was a black body) and +0.1°C was the value for the heat capacity of the greenhouse air.
Since well-water flow rate was included in its parameters, this model also would be applicable to cases in which the well-water flow rate is different from the value used above.

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The amounts of Cd in the silkgland, integument, fat body, malpighian tube, trachea, head part, alimentary canal and sexual organs of the silkworm larva were studied by the atomic absorption method on the 5th day after the oral administration of Cd, Cd·Zn, or Cd·EDTA at the beginning of the 5th instar of germfree silkworms.
1. The amounts of Cd in the tissues and organs decreased when an artificial diet that included both Cd and Zn was given in comparison to a diet that included Cd alone.
2. Because of the oral administration of Cd·EDTA through an artificial diet, the amount of Cd greatly decreased and very little was accumulated in most tissues and organs.
Therefore, the significant inhibition of Cd toxicity when EDTA is added to an artificial diet seems to depend on the stability constant of the Cd·EDTA complex, which is excreted easily from the larval body.

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Two groups of male Rosefinches were pretreated with short photoperiods (8L : 16D) for 60 days to eliminate refractoriness. One group was continued under the same treatment for another 120 days, and the other was transferred to photostimulatory long photoperiods (15L : 9 D) for 70 days. A group of birds having testes of minimal size (combined testicular weight=5-8 mg) was also exposed to natural daylength. Periodic laparotomy during exposure to long photoperiods indicated that gonadal growth occurred in birds on long daylengths followed by regression (photorefractoriness) . Short photoperiods, in contrast, did not initiate testicular recrudescence. NDL birds also showed testis growth on experiencing the increasing daylengths of summer. The results demonstrate that the Rosefinch is a photosensitive bird in which short photoperiods are ineffective while long photoperiods induce gonadal recrudescence which is followed by regression, with continued exposure to long daylengths.

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The use of a response curve to analyze plant-environment relationship is restricted by many reasons; two of which are difficulty to maintain environment constant, and inadequate choice of a function which is easy to compute. Here we proposed a method to estimate a response function which eliminated above two problems. Examples of flower development of Paphiopedilum were processed by this method using the skewed Gaussian function as a response function. Parameters considered were maximum response, optimum temperature, temperautre tolerance, and suitable temperature range. Thus, the flower development in this determined to occur over narrow suitable temperature range, was high temperature tolerant, and showed low temperature response. The use of these parameters in classification of plant ecological charac-ters is considered to be promising.

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