Thirty-two varieties of wheat plants (Triticum aestivumL.) were cultured on vermiculite under various monochromatic lights, white light or darkness at 20°C for 12 days. The lengths of the sheath or blade and the angle of blade inclination of the first leaves were compared to culm length in adult plants grown under field conditions.
1) Considerable differences in sheath and blade lengths were found among the varieties under all the light or dark conditions. The sheath and blade lengths under experimental conditions were positively correlated with the culm length in adult plants under field conditions.
2) Under blue irradiation, blade inclination was promoted in all varieties, and the inclination angles were about 100°. Under red and white lights, there were remarkable differences in inclination response among the varieties. Blade angles showed a positive correlation to the culm length in adult plants grown under field conditions. Correlation coefficients of the blade angle to culm length were 0.863 in red light and 0.607 in white light. The relations between blade angle and the sheath or blade length under experimental conditions were similar to those for culm length. Under green light and darkness, there was scarcely any blade inclination in any of the varieties.
3) The detailed examination of the relation between the blade inclination angle and culm length under red light showed that the wheat varieties used could be classified into two groups. Blade inclination response was promoted in wheat varieties with a culm length of 100 cm or more, but was scarcely promoted in those with culm length of less than 100 cm. In the former group, blade angle and culm length had a positive correlation.

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Physiological and ecological effects of apple trees grown under an artificial environment were studied from bud burst to harvest. Scions having a few dormant flower buds on three apple cultivars were grafted on young rootstocks, and grown in a growth-chamber. (These small apple trees flowered two weeks after being kept high temperature.)
Three to four weeks after pollination, many fruits dropped from these trees as June-drop.
A few fruits retaining grew normally until harvest and had a high sugar contents. Fruit coloring of ‘Tsugaru’ and ‘Fuji’ was normal and more desirable at lower temperature.
‘Nero-26’ apples had a light-color under this condition.
The results indicate that temperature conditions in the growth-chamber were suitable for fruit growth of apple trees, except at an early growth stage. A supply of short and long wave radiation seems to be necessary for better coloration of apple fruits.

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In previous papers, it was made clear that transpiration and stomatal aperture can be estimated by monitoring leaf temperature under controlled environments. Since the photosynthetic rate is closely related with transpiration and stomatal aperture, whether it is possible to determine the photosynthetic rate by monitoring leaf temperature under the controlled environment was examined.
The results of the experiments are as follows. When the light was switched on, leaf temperature and photosynthetic rate increased and after leaf temperature reached its maximum point it decreased though the photosynthetic rate continued to increase. Up to the maximum point of leaf temperature, the photosynthetic rate was closely related with the increase of leaf temperature. On the other hand, after the maximum point of leaf temperature was reached, the photosynthetic rate rose relevant to the decrease of leaf temperature. This relationship was not observed before 12 min after light-on. When either a weak or strong water stress was forced onto the root of the plant by turning the water culture supply on and off, leaf temperature and the photosynthetic rate began to oscillate in an inversely corresponding relation.
The relationship between photosynthetic rate and leaf temperature was investigated and partly elucidated. Computer control can be performed easily if the characteristics mentioned above are memorized by the computer and optimal manipulation of environment is selected by processing of the monitored leaf temperature.

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