The viability of eggplant seeds is controlled by D and FR at low (25°C) or high (35°C) temperature pretreatments after the onset of imbibition.
The seeds pretreated by FR at 25°C or D and FR at 35°C are beneficial for viability during the storage periods, while those pretreated by D and 25°C and unpretreated progressively reduced in viability. The seeds pretreated by FR at 25°C or D and FR at 35°C are induced to the secondary thermo- or photo-dormancy, but those pretreated by D at 25°C are led to the deterioration in the viability of germination.

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Two experiments were conducted to study the effect of temperature during developmental stages of inflorescence on flower bud abortion in Gymnaster savatieri Kitamura.
Plants were grown for 4 weeks from Feb. 2 to Mar. 9 in natural light phytotrons in which day temperature was set at 25, 30 or 35°C, while night temperature was kept constant at 5°C. Temperatures above 30°C markedly induced flower bud abortion of blindness type (characterized by necrotic disk and ray florets), entire necrosis of disk florets type (characterized by necrotic disk florets and undeveloped ray florets) and partial necrosis of disk florets type (characterized by central disk floret necrosis and well-developed ray florets) .
Plants were placed in a natural light phytotron at 33/28°C (day/night) from inflorescence developmental stages until flowering. The type of abortion induced was dependent on the developmental stage of high temperature treatment. Blindness type occurred from the involucre stage to the late stage of petal formation. The percentage of blindness type was high from the involucre stage to the middle stage of petal formation. Entire necrosis of disk florets type occurred from the late stage of petal formation to the complete stage of petal formation. Partial necrosis of disk florets type occurred from the late stage of petal formation to the budding stage. The percentage of partial necrosis of disk florets type was high when the petal formation stage was complete.

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Continuous cropping fields as an environmental factor on cucumber wilt pathogen were discussed. In cucumber or soybean field infested with Fusarium oxysporum f. sp. cucumerinum where crops were double cropping annually, chlamydospores of the pathogen changed to active form after cultivation of crops. In sorghum field the number of active forms was less than in cucumber field. In non-cropping field activities of the pathogen were not ensured. Although the pathogen grew and formed conidia in each crop rhizosphere, they turned more quickly to dormant stage in natural soil of non-host plant fields than the soil of host plant field. When cucumber was cultivated in each continuous cropping field, Fusarium wilt occurred only in cucumber field, but root damage more or less appeared in all fields. The damage, however, were slight in sorghum field, moderate in soybean field and severe in cucumber field.
The virulent pathogen was found more on the roots of cucumber than those of soybean and sorghum. However virulence of the pathogen in a field was subjected to the kind of cropping field. The cucumber field would offer favorable environments for the pathogen, especially for virulent isolates. On the other hand, the sorghum field would offer bad conditions. Accordingly, it is suggested that there were two types of pathogenic isolates, sensitive type and non-sensitive one as a suppressive factor, and this suppressive factor was obliged to ineffective when the population of an isolate in the field increased.

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The objective of the present study was to obtain basic data regarding the NFT system with nutrient cooling during summer. Thermal and flowing aspects in the growth of petty tomato cultivated in channels with different NFT solution cooling method and thus, with different solution temperature were described.
Temperature of nutrient solutions cooled using refrigerator could be maintained close to the setting temperature (22°C) while that cooled by means of cool ground water was some degrees higher than that level of temperature during hot weather. When the cooling systems was not be operated during hot weather, the nutrient solutions reached temperatures of about 32°C.
Temperature distribution in tomato crop was measured. Results showed that the temperature difference between tomato crop cultivated in NFT system with solution cooling using refrigerator and that using cool ground water was 2-3°C and 7-8°C (maximum) in root and stem, respectively.
It was sunny days with very high air temperature inside the greenhouse during early period of growth. The flow rate of nutrient solutions was maintained at 3 liters per minute. Under such conditions, the solution temperature increased 1°C (maximum) when it flowed in cultivation channel for a 10 m distance. Heat gained by the nutrient solutions when it flowed in the cultivation channel under such conditions was about 0.21 kW.
The stage and condition of growth of tomato root was described using the resistance coefficient of solution flow in the cultivation channels. Furthermore, the resistance coefficient was described using the Manning's equation.

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Rapid changes (CFI) in intensity of chlorophyll a fluorescence during dark-light transient reflect the various reactions of photosynthesis. The image analysis of CFI gives information not only about the localized differences in photosynthetic activity on whole leaves in situ but also on the development of photosynthetic system.
Development of the photosynthetic system in cultured tissues is very complex. Therefore, the development of carrot (Daucus carota L. cv US-Harumakigosun) tissues was studied by the image analysis of CFI. The nodular callus, which had been formed by culturing 1-weekold hypocotyl segments on MS agar medium containing 2, 4-D (1 mg⋅l^-1), was used for the experiments. After the nodular callus was transplanted to MS agar medium without 2, 4-D, the embryogenic cells appeared within 2 to 3 weeks. The tissues grew under 25°C air temperature and 80 μmol photons⋅ m^-2. sec^-1. At 3 days after the transplanting, the appearance of chlorophyll a in the nodular callus was detected by the CFI images. The CFI patterns changed in the development of photosynthetic apparatus of developing leaves. The changes in each developing stage were very complex but the progress in the photosynthetic system was diagnosed by the CFI curves. The CFI pattern of the developing leaves at 60 days after the transplanting were similar to the typical pattern of mature leaves.

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