Morphological features of the development of epicuticular waxes and stomatal complexes of leaves in a clone of satsuma mandarin (Citrus unshiuMarc) were examined by scanning electron microscopy. By the early stages of stomatal development the epicuticular waxes in the form of sand or rodlet had already been excreted sporadically on the surface of epidermal walls. The waxes were then crystallized as amorphous platelets on the surface and thereafter the crystalline portion increased with leaf age. The solitary large-sized stomata (giant stomata), surrounded by a number of normal-sized ones were found at intervals over the surface. The density of stomata was lowest at the base of leaf, greatest at the middle, and intermediate at the tip. The substomatal chamber was continuous with the intercellular spaces in the spongy parenchyma. Several pores were observed in the bottom cell wall of the substomatal chamber.

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NFT system of strawberry with semi-forcing culture were tried in three types of beds. Generally, there are very few differences in quality and quantity between soil culture and NFT of strawberry with forcing culture. But, on average, we could yield more than 600 g per each plant which is twice as much as the yield of soil culture.
Observing the state of plant growth carefully, pH and EC of nutrient solution were controlled very differently from those of usual NFT culture. And by comparing the plant growth of each beds, it was cleared that the space between planting panels and surface of nutrient solution had very significant meanings. Namely, forms of rooting were different diffinitely according to the spaces. The spaces of several ten millimeters were considered very effective for primary rooting. But the spaces had a tendency to cause ill-balances between vegetative and reproductive growth. So cultivation with well-balanced forms of primary and secondary rooting are demanded.

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The function of the elected pneumatophores of two mangrove species, Avicennia marinaand Sonneratia alba, was investigated. Experiments were carried out with detached samples from the habitat in order to clarify that the photosynthetic reaction takes place at the surface of the pneumatophore and plays an important role in the gas exchange between the pneumatophore and the root in the subsoil.
As a result, the gross photosynthetic rates of the pneumatophores ofA. marinaandS. albawere 3 and 11 mgCO₂/dm²/hr, respectively, at the light intensity of 0.45 cal/cm²/min. Their light compensating points were at 0.02-0.03 cal/cm²/min and similar to that of a shaded leaf. The diffusion rates of O₂from the pneumatophores to the roots in the light condition were higher than those in the dark condition. In addition, O₂diffusion rates increased when the pneumatophores were supplied with CO₂through their cut surfaces.
These facts show that O₂is produced by the photosynthetic reaction in the pneumatophores during daytime. Then O₂diffuses to the root in the subsoil where it is used for the root respiration. In addition, the respiratory induced CO₂diffuses to the pneumatophore and is used for the photosynthesis in the pneumatophore.

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The function of the elected pneumatophores of two mangrove species, A vicennia officinalis andSonneratia alba, was investigated in Thailand. In order to clarify that the photosynthetic reaction takes place in the pneumatophore and that the O₂produced by this reaction diffuses to the root in the subsoil, the CO₂exchange rate through the surface of the pneumatophore and the O₂concentration in the root were measured in situ.
As a result, gross photosynthetic rates of pneumatophores ofA. officinalisandS. albawere 0.8-1.2 mgCO₂/cm²/hr and 1.0-2.8 mgCO₂/dm²/hr, respectively. The O₂concentration in the root increased from 13.9% to 16.7% when the solar radiation increased from 0.7 calf cm²/min to 1.2 cal/cm²/min. This concentration decreased rapidly when the pneumatophore was shaded.
In conclusion, it was proved that the elected pneumatophore actually produced O₂by the photosynthetic reaction and that such O₂diffused to the root in the subsoil.

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This paper reports the method to measure the stem diameter variation of vine tree (Kyoho) by using a strain-gauge type micro-displacement detector and its application to analyze water content in plant tissue. Our purpose is to establish how to control soil moisture conditions for the restricted root sphere cultivation of Kyoho tree. The results of this study are as following.
(1) The optimal measuring portion of stem diameter variation were the cane.
(2) The relationship between stem shrinkage and water potential in stem tissue were expressed as linear regression lines with high coefficient of correlation.
(3) The water deficit of the tested vine trees were easily analyzed by the stem diameter measurement.
(4) The water content variation was mainly affected by the irradiation intensity and secondarily by matering to the soil.

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Cultivating support system is designed and examined based on the CICS (Computer Integrated Cultivation System), system of which has the computer network composed of both usual micro-computer for environmental control of crops and the special computer for the artificial intelligence. In the system, four sub-systems are prepared; these are“LAN”, “Identification and Control”, “Expert System”and“Agricultural Strategies”.“LAN”and“Identification and Control”are usually engineering problem. On the contrary, “Expert System”is more biological and use of AT computer is inevitable. Whole cultivating process of the crop is supported by these sub-systems. In the important stage through the whole cultivating term, the status of the crop is able to be discriminated based on the AT computer. Thus the adequate set-point of the environmental control could be decided based on the status of the crop. Finally, the sub-system for“Agricultural Strategies”is expected as CIM in agriculture, in other words, as the high-level decision from the point of management view. In this paper, the tomato cultivating support system is discussed, where an expert system is designed for the adjustment of EC'set-point in the NFT. As the results, it seems evident that the expert system may be reasonable and that CICS proposed in this paper should be the most reasonable system.

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In order to develop the environmental control system based on plant responses, the bioelectric potential transition patterns on Spinach lamina in response to light-on were measured as an useful plant physiological information.
The obtained results are summarized as follows;
1) This Bioelectric potential transition patterns when light on were changed by air temperature, relative humidity, CO₂concentration, light intensity, plant growth and dying process.
2) One specific peak of this pattern was related with the rate of photosynthesis.
3) This peak related with photosynthesis was similar to photoelectric potential pattern on spinach chlorophyll in response to CO₂concentration.
4) A vibration of the bioelectric potential appeared in photoperiod, and the ampritude and cycle time of this vibration were increased by decrease of CO₂concentration or increase of light intensity.
5) Therefore, it is possible to hypothesize that the bioelectric potential on lamina is superposition of bioelectric potentials on chlorophyll due to the photosynthesis and respiration.

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Photographs taken from a balloon were utilized in the description of a vegetation map of mangrove forests in Chantabri and Phang-nga, Thailand.
The use of satellite data has presented an entirely new development for observing vegetation and landscape patterns in ecological studies. However, while the satellite technique is suitable for research on large-scale ecological systems, it does not provide the detailed information needed for projects such as vegetation mapping surveys.
For obtaining detailed vegetation maps of certain mangrove forests, a balloon-mounted aerial photographic system was produced. The balloon system is a simple mechanism which offers ease of operation as well as economical production costs. It is thus especially useful for field survey applications in South-east Asia.
The functional characteristics of the system are as follows.
1) It is easy to discriminate mangrove species by observing the difference in color of the forest crowns in the aerial photographs taken from the balloon.
2) Detailed vegetation maps can be efficiently drawn up by combining aerial photographs and ground surveys.
3) The vegetation map was described using an image-analyzing computer. Although the number of sphere extractions was reduced to half in comparison with visual classification methods, this analyzing method is adequate for describing the main canopy composition of the forest.

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The changes of both chlorophyll concentration in the leaves and sugar concentration (Brix %) in the fruits were measured periodically for melon during its maturing stage. Whereas the chlorophyll concentration remained nearly the same level in the top leaves, it gradually decreased in the leaves closest to the melon fruits. The ratio of the latter chlorophyll concentration to the former was closely related to the sugar concentration in the melon fruits. The sugar concentration linearly increased as the ratio decreased; it stopped increasing after the ratio decreased below 0.36. This result suggests that it should be possible to judge the maturity of netted melons by monitoring the changes in leaf color.

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The leaf color of netted Melon plant was periodically measured using the color computer during its maturing stage. The color difference between the green upper leaf and the lower closest leaf to the fruit was measured. The upper leaves remained the same color, but the lower leaves turned their color. The daily course of the sugar concentration was measured.
The result showed that the color difference indicated the optimum harvest time of the fruits and the increased sugar concentration of the fruits.

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