Potted fig (Ficus carica L. cv. Masui Dauphine) cuttings were subjected with 0 or 50 mM NaCl solution for 4 weeks. Stem elongation, photosynthesis, transpiration, and mineral content in plants and latex were measured in a time course. Growth, photosynthesis and transpiration were suppressed by NaCl. Greater amounts of Na⁺ and Cl^- ions accumulated in leaves and stems than in roots. The NaCl treatment decreased K⁺ and Ca²⁺ in all plant parts except leaves. The osmotic potential of exuded latex was significantly decreased by the NaCl treatment. Na⁺ content of the latex was considerably lower than that of leaves or stems, while the Cl^- content was approximately equal to that of leaves or stems, suggesting a high capacity for the exclusion of Na⁺ by membranes of the laticiferous cells.

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The growth changes caused by the increase of far-red light were investigated in pole-type and bush-type kidney beans (Pheseolus vulgaris L. cv Kentucky Wonder and Celina) . Irradiation with a wavelength over 700 nm was added to the fluorescent lamps to increase far-red light. The light quality variation with supplementary far-red light was presented by phytochrome photoequilibria (P_fr/P) . To estimate the P_fr/P, the SPD method was used, which was calculated by the spectral photon flux distribution of irradiation and the phytochrome photoconversion. The calculated P_fr/P was compared with the measured P_fr/P derived from the method of Holmes and Smith (1975) . The calculated P_fr/P was expressed in a rectangular hyperbolic equation of the R/FR ratio, and this P_fr/P and the measured P_fr/P showed low level difference (<8%) . Therefore, by using the SPD method, estimation of P_fr/P could be possible without the analysis of phytochrome. As the far-red light increased and P_fr/P decreased, the length and dry weight of the stem in both the pole-type and the bush-type kidney beans increased and the proportion of the stem dry weight relative to the whole dry weight increased. The increase of stem length was great when the P_fr/P was above 0.77, and small when below 0.77. The stem length increased through increases of both the number of nodes and the internode length in the case of pole-type, while in the case of bush-type beans, only through the internode length.

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The crown in a tea garden is defined as a bell-shaped surface layer in which tea leaves are aggregated. We considered that photosynthetic productivity in the crowns was correlated closely with the position of leaves and relative illuminance. In this paper the activities of CO₂ uptake and ferricyanide-supported O₂ evolution, chlorophyll content and chlorophyll a/b were measured to clear the light environment of crowns in connection with the spatial position of leaves. The maximum rate of CO₂ uptake was attained at least twice a day (8-9 a.m. and 1-2 p.m.) regardless of leaf age and illuminance. The CO₂ uptake by 1-year-old, not newly-formed, leaves located about 50 cm above the ground was saturated at low PPFD, suggesting shade-type of leaves as supported by plotting CO₂ uptake against PPFD. The O₂ evolving activity of isolated chloroplasts was found to be higher in winter. These results suggest that newly-formed tea leaves are sunlit and change into the shaded leaves at the lower position of the crowns in the period from autumn to winter.

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In order to investigate the seasonal change of transpiration in mangrove species, the sap flow rates (F_s) in Bruguiera cylindrica were measured in southern Thailand, with a stem heat balance method. From the result, the transpiration rates (T_r) normalized by leaf area in wet and dry seasons were estimated to be 0.50 and 1.04 kg m^-2 d^-1 on the average, respectively. T_r in the dry season was rather high compared to that in the wet season. This was probably caused by the difference of meteorological conditions, such as solar radiation and air humidity. Moreover, stomatal conductance (gs) in 4 species, Rhizophora apiculata, Ceriops decandra, Xylocarpus moluccensis and B. cylindrica, was measured in the wet season with a porometry to investigate its interspecific difference. In all the species, g_s reached a plateau at the PPFD of 200 to 400μmol m^-2 s^-1. The plateau in R. apiculata was estimated to be between 150 and 250 mmol m^-2 s^-1 ; the level is similar to that in evergreen trees in Japan. However, g_s in the remaining 3 species was rather low.

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Recently, some genera of orchids are cultured on highlands about 600 to 800 m in altitude or in cooled greenhouse during summer to promote flowering in Christmas season. However, these methods require laborious work or large utility expenses. In this study a spot cooling system using a spot air-conditioner, which is economical and easy to handle, was provided for cultivation of Zygopetalum, Dendrobium and Phalaenopsis. The bench (1.2 m × 9.6 m × 1.1 m) for spot cooling was covered with heat insulating material and then tunnel-shaped covering material, 1m in height, was placed over the bench, and cool air was channeled into the tunnel. The plants in pots were placed on the bench in the tunnel from 11 August to 28 October. The air temperature of the cooling spot was maintained 4 to 7°C cooler than that on the control bench without spot cooling. All the orchid plants grown under the spot cooling system flowered approximately a month earlier than the control plants. Thus, spot cooling was proved to be effective in promoting flowering of the orchids.

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Seasonal variations of fatty acid composition in bark tissue of newly produced twigs of Japanese pear “Nijisseiki” were measured from August to March to investigate their relation with cold hardiness and air temperature. The changes of fatty acids and cold hardiness from August to December were associated with the variations of air temperature, and from January to March, were more related with the growth stages. An increase in the proportion of linolenic acid (C_{18: 3}) and slight decrease of linoleic acid (C_{18: 2}) in galactolipids coincided with the development of cold hardiness of twigs from August to November while the trees were dropping into endodormancy stage. Thereafter, the change was reversed as the cold hardiness decreased during January and February, paralleled with the processes of endodormancy overcome and bud swell. In contrast, the proportion of fatty acids in phospholipids showed different profiles of variations from autumn to early spring, which were increases of C_{18: 2} proportion and decreases of oleic acid (C_{18: 1}), palmitic acid (C_{16: 0}) in phospholipids paralleled with the development of cold hardiness. Higher unsaturation of fatty acid in total lipid was occurred in December while pear obtained the strongest cold hardiness. All individual lipids increased from August to February, and a marked increase occurred from September to December. The alternation in membrane lipid and fatty acids during endodormancy seems like an important and necessary process, resulting in overcoming endodormancy and developing greatest cold hardiness finally. Likewise, the favored conditions of membrane lipids for developing stronger cold hardiness in mid-winter and the growing of buds in early spring were similar in the bark tissues of Japanese pear.

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Enhancing coloration of fruit of lightly pigmented sweet cherry fruit (Prunus avium L. cv. “Satohnishiki”) was attempted by postharvest irradiation with UV rays. UV rays irradiation at 2.35 W m^-2 alone markedly promoted red color development and increased the anthocyanin content in the skin within 48 h. No additional effect was found when white light was combined with UV. The red color development proceeded even in the dark after UV irradiation, although the degree of coloration depended on the duration of the irradiation. By lowering the temperature during irradiation, from 23 to 11°C, the effectiveness of UV irradiation was suppressed. The weight loss of the fruit during irradiation increased with the intensity of irradiation, while it decreased at lower temperatures. The soluble solids content or firmness of skin and flesh were not appreciably affected.

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Exergy of air including odorous gas components was considered in order to decide the optimum air flow rate for filtering odorous gas components by soil cover. Filtering odorous gas components gives a comfortable feeling to man. It means that the purer air has a higher quality for human life and the cleanliness of the air is related to the exergy which shows the degree of quality of every kind of energy. From the above view point, the author defined the exergy of air under deodorization process regarding the raw air exhausted from stock farming as being at the standard condition. The difference between the exergy of pure air and that of raw air expresses difference in quality, and this difference is related to the odor intensity of the raw air. From the results of an NH₃-air system for example, there seemed to be a non-linear relation between the exergy of air containing odorous gas components and its odor intensity. The overall efficiency of the deodorization process ε was shown to be a product of exergy efficiency η and the effectiveness of soil bed use as a medium for deodorization ζ. Based on the overall efficiency of the deodorization process, the optimum flow rate of raw air was estimated to be proportional to the rate of deodorization for the NH₃ filtering process. On the other hand, the optimum flow rate of raw air seemed to depend on the reaction rate constant k_B and the overall mass transfer coefficient Ka for the H₂S filtering process.

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Quantification of leaf spot (leaf damage with yellow spot) in Saintpaulia (Saintpaulia ionantha H. Wendl. cv. Ritali) was conducted by using an image analysis technique. Clear images without distortions or shadows were acquired by using a transmitted light from underneath the leaf. Quantification by the image analysis has very high correlation with that estimated by weighing the replicas of photograph. Furthermore, images analyzed by using an image editing software corresponded very well with the micrograph photographed under a fluorescence microscopy. These results indicate that the proper use of the transmitted light can provide precise quantification of leaf damage, even if it is characterized by a very complex pattern as leaf spot in Saintpaulia.

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The effective thermal conductivities for longitudinal and transverse heat flow in the central parts of corn and sunflower stems were measured using the line heat source method. Most of the effective thermal conductivities of the plant stems were found to be less than 0.2 W m^-1 K^-1, with the exception of samples having a high water ratio. These low values are probably attributed to the high gas ratio in the central parts of the plant stem. The difference between the longitudinal and transverse thermal conductivities of the plant stems was not found to be significant.

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