A critical study was carried out to find such a new systematic method of grape culture as to be able to supply fresh grapes at any time throughout the year even in high latitude region as in Japan. Two-year-old grapevines, cv. ‘Kyoho’ were stored in a bundle containing 10 vines in the refrigerator at 1°C and planted in every month during the current season of 1976. Shoot growth, development of floral organs, berry growth, and the size and quality of berries at harvest were compared among different planting times.
Effect of different storage temperatures on the growth and development of vines planted in the fall of 1976 was also examined.
1. Growth cycles of the grapevine were affected not only by the length of storage period, but also by the climatic conditions after planting. The longer the storage period, the poorer the floral development and subsequent berry growth became, especially when the vines were planted in July or August.
2. Shoot growth was extremely reduced under short day conditions when the vines were planted in and after September. It is necessary, therefore, to supply artificial light during fall and winter season.
3. Berry size in any of stored vines was smaller than that in the control, and was at best 65% of the control in July and September planting. Berry quality was best in May planting, provided that the size was a slightly smaller than the control.
4. Among the different temperatures during storage period, shoot growth and berry quality after planting were poor when the vines were exposed to the lowest temperature (-2°C), but were favorable when exposed to a higher temperature (4°C), though degree of rot and infection of the roots by microorganisms were severer.

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The effect of monochromatic light and the interaction of blue and red lights on leaf blade inclination in wheat plants) Triticum aestivum L., cv. Shirasagi-Komugi) were studied.
1) Blue light caused inclination of the blades of the first leaves. When 7-day-old seedlings grown in darkness were exposed to blue, green, yellow, red, far-red and white lights, and to darkness for 72 hours, the angles of the leaf blade were 113°, 13°, 13°, 14°, 30°, 30° and 12°.
2) The spectral regions effective for inclination were the wavelengths between 380 and 510 nm, with a marked response at 430-480 nm.
3) Blue light of 2000 erg/cm²/sec was fully effective, the maximum inclination response was obtained 72 hours after the start of irradiation. Photosensitivity to blue light showed a maximum response 2-3 days after the laminar joint appeared from the top of the coleoptile.
4) Red or yellow lights applied simultaneously with blue light counteracted inclination. The counteracting spectral regions appeared at wavelengths between 560 and 690 nm with a marked response at 630-640 nm.
5) The counteracting effect of red light on blue light differed with the mixed ratio of red light to blue light (R/B ratio) . The blade angle of leaves in wheat plants exposed to blue light (2000 erg/cm²/sec) for 72 hours was about 100°, whereas the angle for the R/B ratio of 1/10 was about 40°, 30° for the 1/4 ratio, 25° for the 1/2 ratio, and 20° for the 1/1 ratio.

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To develop the commercial cultivation of Pholiota adiposa, experiments were carried out using a substrate of sawdust and rice bran which has been conventionaly used as the basal substrate in most mushroom farms of Flammulia veltipes in Japan. A mixture of ingredients (sawdust, rice bran, and water) was placed in 800 ml polypropylene bottles (9 cm in diameter, 16 cm deep), which were sterilized at 100°C for 6 hr. Then the seed spawn was inoculated to the medium. The spawn-run was best on a substrate containing sawdust and rice bran in a ratio of 5 : 1 (v/v) with about 70% water. The mycelia grew fastest at 20-25°C, but an ambient air condition with 50-70% RH at 18°C in the dark was fairly good for a stable spawn-run. A combination of the above conditions completed the most favorable spawn-run with 23 days. Either paper covers or polypropylene caps with side crevices for the bottle could be used, but airtight covers inhibited the growth.

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Further experiments for developing the commercial cultivation of Pholiota adiposa were carried out. When the spawn-run was completed, the exhausted spawn on the substrate was removed with a raking machine (surface-clearance) . This treatment was essential for subsequent fruiting. Maintenance of sufficient moisture in the uppermost layer of the substrate was also required for fruiting. Therefore, the substrate was imbibed with water overnight just after the surface was cleared, after which polypropylene caps with side crevices were used again on the bottles until pins appeared. These treated bottles were then incubated at 18°C and 90-95% RH under dim light, and abundant pins appeared 12 days after surface-clearance. After the appearance of the pins, the caps were removed and the bottles were watered regularly twice a day with a sprinkler; normal development of fruit-bodies followed. Thus, the first pick was obtained within 26 days after surface-clearance.

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Using the bivoltine silkworm race (Hosho), we investigated the effect of light of different wavelengths during larval rearing on diapause in the next generation. The larvae hatched from eggs that had been incubated at 25°C, 24L were reared on the artificial diet containing 50% mulberry leaf powder under the long day condition (24L and 20L4D) .
We found that light in wavelengths from 400 nm to 540 nm affected the production of nondiapause eggs, and that the 20L4D light group produced more nondiapause eggs than the 24L light group. Moths that emerged early tended to produce nondiapause eggs, but when the larvae were reared on fresh mulberry leaves, nondiapause eggs were not produced under any light condition.

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In previous paper, the flower stalk development promoted by low temperature dropped by step has been given as a mathematical model of the first order lag curve, where the asymptote and the delay have been used for evaluating the effect of the low temperature condition. The present paper deals with modifications and development of the mathematical model with the effect of temperature dropping gradients in course of time : The parameters of log₁₀ (td+α) and log₁₀ΔT ^1/2⋅td² which evaluate the low temperature effect were converted to log₁₀ (tm+β) and log₁₀ ΔT^1/2⋅tm² where ΔT, td and tm are a degree of low temperature, treating duration with low temperature and the period settling to constant 5°C in temperature dropping with gradient, respectively, and α andβ are constancy. These parameters were useful for representation of the flower stalk development promoted by low temperature dropped by gradients. Thus, the temperature dropping gradient is able to be used as an important parameter in the present model which indicates that the low temperature effect on the flower stalk development changes with the temperature dropping gradient; the functions evaluating effect of the low temperature dropped by step are modified with a parameter (tm) expressing the temperature dropping gradient. From this mathematical model, it is concluded that the effect of low temperature on flower stalk development is enhanced by the temperature dropped with gradient additively and multiplicatively.

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The effect of SO₂ on transpiration of various plant species was tested. The pattern of changes in transpiration rate during the course of SO₂ fumigation was significantly different between plant species. Fumigation with 2.0 ppm SO₂ induced the rapid decline of transpiration rate of rice and tomato. In other plant species, the transpiration gradually decreased with or without initial increase. Those plant species with rapid decline of transpiration rate were generally more tolerant to SO₂ than the species with gradual decrease of transpiration rate. However, this speculation is not always true. For ginkgo plant, the increase in transpiration rate was observed for about 3 hours with no visible injury.

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The effects of NO₂, SO₂ and O₃ singly and in combinations on the rates of net photosynthesis were examined for intact leaves of sunflower (Helianthus annuus L. cv. Russian Mammoth) . Concentrations of air pollutants used were 1.0 or 0.2 ppm for NO₂ and 0.2 ppm for both SO₂ and O₃.
Exposures to 1.0 ppm NO₂, 0.2 ppm SO₂, or 0.2 ppm O₃ separately caused no detectable depression of photosynthetic rates, but combinations of these two or three gases measurably reduced the rate to a greater degree than would be expected from the sum of the inhibitions caused by individual gases. NO₂ concentration in NO₂/SO₂ mixture was the variable that determined the degree of photosynthesis inhibition, but the magnitude of the photosynthesis depression caused by NO₂/O₃ or NO₂/SO₂/O₃ mixture was not influenced by the concentrations of NO₂ in the mixture.
The rate of photosynthesis inhibition caused by NO₂/O₃ mixture was quite different from that caused by SO₂/O₃ or NO₂/SO₂/O₃ mixture. The mixture of NO₂/O₃ decreased the rate of net photosynthesis steadily with duration of exposure, while the mixture of SO₂/O₃ or NO₂/SO₂/O₃ caused the rate to depress rapidly to the new equilibrium inhibition level.

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