Soluble solids content (SSC), titratable acid and sugar composition (fructose, glucose and sucrone) in different portions of `Okitsu wase' satsuma mandarin (C. unshiu Marc.) fruit were determined at harvest. Increasing gradients in SSC and sugar content were noted from the stem end toward the stylar end, and from the central portion toward the outer portion. The sucrose content in different portions of fruit was higher than hexose. The sucrose/hexose ratio was the lowest in the middle portion of the equator. The acid content was higher in the equator than in the stylar and stem ends. Moreover, the content was lower in the outer portion than the central and middle portions. The SSC/acid ratio was highest in the stylar end, followed by the stem end and the equator. The higher the SSC in the stylar end, the greater the difference in SSC between the stylar end and the stem end. Likewise, the higher the acid content in the equator, the greater the difference in acid content between the equator and the stylar end. Regression coefficients of SSC, acid content and SSC/acid ratio with their respective means in the different portions of fruit were relatively high in the equator portion. In conclusion, this means that the equator is a reliable portion for non-destructive evaluation of fruit quality with infrared sensors.

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The purposes of this paper is to clarify the soil temperature characteristics of pots in glasshouses. For this purpose, three different pot conditions were prepared using Wagner pots (1/2000a). The diurnal variation of theoretical direct solar radiation on the pot wall varied according to the directions of the pot wall. The rise of the temperature of pot soil without the presence of a plant at a certain elapsed time after sunrise was assumed to he proportional to the amount of solar radiation. The effects of the plant canopy on the diurnal variation of the pot soil temperature in a glasshouse and in a climatoron were smaller than those observed in the field. In the daytime, the plant canopy significantly affected the deviation of the pot soil temperature at each point in a pot, but at night, plant and other environmental factors did not. The deviation of soil moisture in the pot differed in relation to the presence of a plant, its position in the pot and the pots position inside or outside of the glasshouses.

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In china, most of the harvested raw paddy is dried by sun drying. However, because the optimum condition for the sun drying is not clarified, a lot of crack grain is generated frequently, leading to the serious grain loss. Therefore, the characteristics of sun drying were investigated using four varieties of paddy from the viewpoints of both drying efficiency and crack rate. The influences of the thickness of paddy layer, frequency of stirring, ground condition, finishing moisture content and shading during drying were considered. The thickness of the paddy layer had the biggest influence on the drying rate. For sun drying on a clear day in September, the proper thickness was about 5cm. The stirring operation is very effective to get a high drying rate and to prevent cracking. Excessive drying leads to so much cracking, so the grain moisture meter should be introduced to manage the drying process.

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The method for mass propagation by cutting of Lathyrus latifolius L. was investigated and the following results were obtained: 1. The rate of difference for rooting and shoot growth was small among soil mix, rockwool and perlite used as a medium for cutting. 2. The rate of rooting and shoot growth at 22℃ was better than that at 15℃ or 8℃. 3. The rooting and shoot growth of a plant under an 8-hr photoperiod was more suitable than that of a 16-hr photoperiod. 4. IBA treatment concentration at 16 or 40ppm was more effective for rooting and shoot growth. 5. No difference between 7 years old and 2 years old stock plant of cuttings was on rooting and shoot growth.

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An automatic coating machine with a simple balance was developed in order to obtain homogenized coating rice seeds by an oxygen supplier of direct sowing rice to a paddy field, and to avoid fling in all directions of the oxygen supplier. It is able to coat and spray automatically both oxygen supplier and water to 3 to 8kg of rice seed. The main feature is a simple balance for the measurement oxygen supplier and use of a rotating drum on the market. The time required to coat rice seeds was from 20 to 39 minutes.

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The purpose of this report is to find the characteristics of fruit and vegetable wholesale markets in China. We studied the changes of the rural traditional market, the developing of the circulation of agricultural products and the investigation into the actual conditions of the wholesale markets presently. We think that the circulation system of China is in its beginning stage and is insufficient in displaying the public effect on society, assuring the stable supply to the consumers. So it is very important to make the rules for the standard management of the wholesale market, and it is necessary to fortify the public effect and order.

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In China, there is a high occurrence of broken rice during the processing stage, husking and milling, which is one of the big causes of grain loss. Measuring the broken rice ratio in the Province of Sichuan, China, that of the hybrid type rice is higher than that of the ordinary type rice. The characteristics of occurrence of broken rice in the husking and milling processes were then investigated for both types of rice. The following conclusions were obtained; i) The broken rice ratio in the husking process is in proportion to the crack ratio of the paddy before the husking. So, it is important to inhibit the crack ratio during the harvesting and drying stage. ii) It is necessary to set the rubber roll clearance as long as a sufficient husking ratio can be obtained. iii) Though the crack ratio of paddy is the same, the broken rice ratio of the hybrid type rice is higher than that of ordinary type rice in both the husking and milling processes. iv) Using an abrasive type rice mill can inhibit the broken rice ratio. v) The broken rice ratio of short rice produced in Japan (Hatsushimo)is very low in comparison with rice of China.

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The objectives of this research were to determine the concentrations of chemicals and physiological activities (CO_2 and C_2H_4 production) in fruits of cherry tomato (Lycopersicon esculentum var. cerasforme Alef. ) cultivar `Petit' at three ripening stages (pale green, Pg. ; partially ripe, Pr. ; table-ripe, Tr. ) and to study the effects of holding period on the physiological response to physical stress. The titratable acid (TA) and free amino acid (AA) concentrations of jelly part were higher than those of pulp part and reducing sugar (RS) concentrations of jelly part were lower than those of pulp part in all fruits at picking time. The TA of both parts in Tr. fruit were the lowest concentration and AA and RS concentrations of those were the highest at picking time. The TA of both parts in Pr. decreased and AA of those increased during holding at 20℃. The CO_2 production of Tr. fruit showed less change, and the CO_2 productions in Pr. and Pg. fruits showed the peak during holding. The C_2H_4 productions in Pr. and Tr. fruits increased and reached the peak on the first day of holding and were followed by decreasing. The C_2H_4 production in Pg. fruit at picking time increased gradually during holding. In all ripeness stages at picking time, CO_2 production increased immediately after physical treatment and showed a steady level for one day. In all fruits held at 20℃, CO_2 production of treated fruits did not show marked increasing after physical treatment, but showed great increasing after one day holding. The C_2H_4 productions in all fruits treated at picking time and held at 20℃ showed great increasing after one day holding.

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The effects of winter mulching on the sprouting and shoot growth of the first crop were studied in a matured tea field that was planted in north-to-south rows and framed in an arc-shape. Mulch treatments and mulching materials influenced the growth of new shoots in different ways. Particularly, the straw mulch treatments (the straw mulch and the cut-straw mulch covered with the transparent plastic film) were superior to other film mulch treatments in the growth of shoots and the yield. Furthermore, it was observed that both the straw mulch treatments could improve the unevenness in the growth of shoots between the western side and the eastern side of canopy surface.

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This paper describes the development of an autonomous steering rice transplanter which utilizes an image processing technique for self-guidance in paddy fields. The rice transplanter was equipped with a red target board and a wireless modem. The host computer, which has a color image processing board that detects the board on the rice transplanter, was set on the end of the row. The result of the experiments show that the rice transplanter was able to move straight along the desired courses, 15 m at the first row and turn into the second row without an operator. The author made a camera following system. Therefore, it was able to follow the sight of the rice transplanter which moved along a crossing line of the camera sight.

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Forty-three tree peony (Paeonia suffruticosa) cultivars were investigated to evaluate the effect of forcing culture on flower coloration and petal pigmentation. Depending on color differences among flowers, cultivars are classified into two specific groups as the insignificantly changed flower color group (19 cultivars) and the significantly changed flower color group (24 cultivars). When forced, b^* values on CIELAB (International Commission on Illumination) color coordinates for the petals of Japanese cultivars decreased but L^* values (lightness) increased. L^* values in the petals of Chinese cultivars did not significantly changes, however, a^* values increased but b^* values decreased on CIELAB color coordinates. Concerning pigmentation, the proportion of peonidin 3,5-di-O-glucoside (Pn3G5G) in the Japanese and Chinese cultivars increased when forced. Total anthocyanins (TA) decreased in both Japanese and Chinese cultivars, thus causing flower coloration to be paler. It is suggested that accumulation of anthocyanins by supplemental artificial light could stabilize the vividness of flower colors.

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