In this report the author investigated the influence of water flow rate and water temperature upon the double roofed greenhouse with spraying of well water between the roofing layers.
1) The ratio of room temperature decrease to ambient temperature decrease was as small as 0.20°C/°C. The ratio became larger when the water flow rate became smaller.
This figure of ordinary greenhouse was usually much larger.
2) The ratio of water temperature decrease to room temperature decrease was about 0.6°C/°C.
3) At lower room temperature, the water flow rate became smaller and the over-all heat transmission coefficient (K) larger.
4) By means of modified heat transfer model, the estimation formula was obtained, showing room temperature as a function of sky temperature, ambient temperature, soil temperature and heat flux emitted from spraying water.
5) The relation between the water flow rate and the room temperature was given as an exponential curve. At the optimum water flow rate range of 6-12 liter/m²hr, the ratio of 1.4-4.5 liter m^-2hr^-1/°C was obtained.

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The effect of dry wilting of petals and leaves on the sporulation ofBotrytis cinerea, the pathogen of gray mold disease, was examined using cucumber, eggplant and strawberry.
Sporulation on petals and leaves was accelerated by lyophilization or air-drying, but it was reduced on those dried at moist chamber and room temperature for 3 days. The increase in the numbers of conidia formed in response to drying was smaller on the petals than on the leaves.
Analysis of the free sugars and amino acids in eggplant petals and leaves revealed no difference between air-dried and non-dried plants, but showed a decrease in the sugar content and qualitative and quantitative changes in the amino acid composition after drying at room temperature for 3 days. The amino acids which decreased during 3 days drying promoted sporulation more than those not decreased by the drying, in the medium containing both amino acids and glucose. Sporulation was promoted at 0.5% more than 0.1% alanine, proline, glutamate, aspartate or methionine.
Judging from these results, the decrease in water content accompanying with the drying of petals and leaves is presumed to enhance sporulation by increasing the concentration of amino acids in the plant cells. After drying for 3 days, the amino acids which promote sporulation decreased metabolically, and then this fact might result in lower sporulation.

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Continuous and nondestructive measurement of plant growth in weight is considered to be one of the fundamental techniques used in studying mutual relations between plant growth and its environment. In the previous paper, a method of weighing growth of plant cultivated in water culture by the use of cantilever beam sensors was reported. In single cultivation, this method had some merits on measuring weight growth of a plant such as was not affected by changes of plant's posture, whereas in community state had demerits such as more channels for measurement and complicated operations were required.
In this paper, developing new measurement system of plant growth in community state was reported. The system was composed of two parts. The one was four load sensors and the other a loading plate. The former was the cantilever beam sensors developed in the previous paper and the latter, supported by the former above a water culture tank, was provided for the purpose of holding plants in community. The net weight of plant in community state could be measured by summing up the outputs of four load sensors and subtracting the weight of the loading plate.
By using these measurement systems and setting light condition showed in Fig. 7, an experiment was carried out for 35 days, in order to measure weight growth ofChrysanthemum coronariumin community state cultivated in water culture. The result was shown in Fig. 9 and the difference between weight measured by the loading plate and by a balance was about 1.5% of total plant weight in community state.

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