A system for non-destructive and continuous measurement of fresh weight was developed consisting loadcell and hydroponics. The readings of the system were not affected by temperature fluctuation, and the hysteresis was little. The readings were in good agreement with the fresh weight of leaf bunching lettuce above the surface of the hydroponic solution, and almost the same as the top fresh weight, when the solution level was high.
Using this system, daily change of top fresh weight was monitored and daily growth rate was calculated. The weight increased from 4.4 g to 102.6 g in 17 days. The growth rate and the transpiration rate were the lowest, when the weight was about 10 g. The growth rate was the highest and the leaf area index was almost optimum, when the weight was about 30 g.
It was concluded that this system can monitor the change of the top fresh weight continuously.

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The light-photosynthesis curve of the seedlings of two species of Betura, Quercus, Acer, and two kinds of Fraxinus grown under three light levels was compared in relation to their specific leaf area (SLA) . With deeper shade, the SLA showed a increase, the largest in both Fraxinus, and the smallest in two kinds of Betula. The half-saturation of photosynthesis of all tree species occurred in a low photosynthetic photon flux density (PPFD), with deeper shade, especially in Quercus. With a reduction of PPFD, the initial slope of the light-photosynthesis curves of two species of Betula showed a slight steepness, whereas that of the other tree species showed a great steepness. The dark respiration rate of leaves of all tree species decreased with a deepening of shade. The photosynthetic acclimation of both Fraxinus was the greatest; this may be advantageous to surviving under a gap created in forest canopy. Two species of Betula had the smallest photosynthetic acclimation to shade, and this characteristic may imply that they can not survive under shaded conditions. The acclimation to shade of Quercus and Acer was observed not in the SLA, but in the photosynthesis; this might be an advantage for conserving photosynthates for expanding leaf area in shaded environments.

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The second internode counted from the top of the rice culm, which is controlled by a single recessive gene (d₁), is unable to elongate more than 5 mm under natural conditions. The elongation of this genetically shrunken internode was induced by high temperature given for one week after flower bud initiation, but not by low temperature. The shrunken internode showed anomalously high IAA oxidase activity as compared with the other internode in the mutant rice plant as well as the second internode in normal rice plants.
The high IAA oxidase activity was decreased by high temperature stress, but not by low temperature. The elongation of this genetically shrunken internode was associated with the decrease of IAA oxidase induced by high temperature. While the shrunken internode was elongated by the supply of 1, 000 ppm NAA solution. Therefore, it seems that there is an inharmonious relationship between auxin destruction and internode elongation in the mutant rice plant.

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