In order to ascertain the effects that a coating method of rice seeds with calcium peroxide have influence on the properties of the coated seeds, a mass ratio of atomized water to calcium peroxide was investigated, using two kinds of calcium peroxide. The test results show that, in order to have uniform coated rice seeds and a balanced coating process, a mass ratio of atomized water to calcium peroxide of 22.8% was necessary. The correlation between the mass of the coated rice seed and its cubic volume or hardness was very linear, and the germination rate of coated rice seeds was low due to their high level of hardness. As a result, the germination rate of coated rice seed was restricted by its mass to below 80mg with "Calper A" calcium peroxide, and to below 90mgwith "Calper 16", and a hardness of 9.6N.

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The method for mass propagation of one-year-old 'Nanko' mume (Prunus mume Sieb. et Zucc.) seedlings for rootstocks was investigated using tissue culture, and the following results were obtained: 1. The shoot growth on a WP basal medium was more suitable than that on MS or B5 basal media. 2. 6-benzyladenine (BA) at 5 or 10μM was most effective for shoot proliferation, whereas zeatin and N^6-(2-isopentenyl)adenine (2iP) were less effective at the same concentrations. 3. IBA or NAA treatment was more effective than IAA treatment on the number of roots and rooting percentages. 4. Rooted plantlets could be easily acclimatized under a mist condition.

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The goal of this research is to determine the optimum pF value that controlls the growth of cherry tomatoes in a water irrigation biomass bark bed. The changes of the transpiration flow rate, the stalk diameter, and the pF value of the bed, in response to changes in light intensity were measured. The response times for the three parameters due to the changes in the light intensity were 10, 9-18 and 8-10 min, respectively. The transpiration flow rates and the pF value were not affected by the latter. The response time of the stalk diameter however, increased with an pF value. The transpiration flow rate decreased with an increase in the pF value. The pF value in the irrigated bark bed should be less than 1.6-1.7 in regards to the growth of cherrv tomatoes.

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The possibilities of bruise detection on fruits by color images were analyzed by using two kinds of apples (Fuji and Oorin). Six kinds of colorimetric systems {RGB, HIS, Lab, xy, rg and U^*V^*W^*) were calculated by the tristimulus color theory on a camera after measuring the spectral reflections on apples. The bruises on Oorin apples could be easily classified by using RGB, XYZ, HIS, Lab, rg or U^*V^*W^*. On the other hand, it was difficult to detect the bruises on the Fuji apples.

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In this paper, the issues in regard to structural, price and income support policies in the New Basic Law on Food, Agriculture and Farming Villages (tentative name ), were analyzed. The following topics were examined : (1) the policy objectives in regard to food, agriculture and farming villages in the above legislation; (2) the questions involved in helping farmers, and the price and income support policies needed to stabilize farm managements; (3) the income support policies needed for farm management in farming villages with economic ploblems; (4) the perspectives and limitation of farm management and agricultural areas in regard to the requisite price and income support policies.

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The main purposes of this paper are: 1) to estimate cost functions and 2) to determine the optimal business intensity and size for turf grass producing farms. The results of this analysis were that the cost functions in the short and long run as well as the correlation between farm business size and turfgrass production could be estimated by a linear function. In other words, the average production cost decreased as turfgrass production increased in the short run and as the size of the business in guestion expanded in the long run. However, optimal business intensity and size could not be determined in this case study, because none of the farms that were analyzed in this study were large enough in regards to business intensity and size in order to show a decreasing return to scale.

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An RC-helicopter that can be controlled easily may be required for the use of farm work in the future. In this paper, a four-rotor type RC-helicopter was made for experiment and the results of its performance tests were reported. The trial RC-helicopter had four rotors which were driven by DC motors. The pitch angle was fixed, and the rotational speed of each motor was controlled by way of PWM (pulse width modulation). They rotated in the opposite direction of each other in order to defeat the reaction torque of the body caused by the rotation of rotors. The test results were as follows: 1. The horizontal adjustment effect of free gyroscope installed on the trial RC-helicopter was good when the tilt angles were -10 to 10 degrees. 2. The maximum lifting force of the trial RC-helicopter was 38.66N when the pitch angle of the rotor was 12 degrees and the rotational speed of the rotor was 1312 rpm. The lifting force of all four rotors was 2.3 times larger than one rotor.

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Rockwool was placed in soil ridges in order to create sufficient aerial spaces in soil for better tuberous root development of sweetpotato. The rockwool was either mixed (the Mixture treatment) or not mixed with soil (the Mass treatment). The water depth between the ridges was kept at 20 mm throughout the growing period in order to imitate the wet soil conditions in lowlands. The growth characteristics and yield of sweetpotato grown in the Mixture and Mass treatments were compared with those grown in a conventional control. The fresh and dry weights of the total phytomass per plant were greater in the Mixture and Mass treatments than in the control. The fresh and dry weights of the sub-ground parts in the Mixture treatment were 2.1 and 2.4 times greater, respectively, than those in the control. Higher fresh and dry weights of the tuberous roots were obtained in the Mixture treatment. The Mixture treatment showed approximately 3 and 2 times greater, respectively, fresh and dry weights of the tuberous roots than in the control. The maximum tuberous root diameter in the Mixture and Mass treatments were 1.5 and 1.3 times greater, respectively, than that in the control. The shoot/root ratio was lower in the Mixture treatment followed by the Mass treatment and a higher shoot/root ratio was obtained in the control. A higher edible biomass index was obtained in the Mixture treatment followed by the Mass treatment and was the lower in the control.

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It is the object of this study to find a method of high quality drying by far-infrared ray. This paper clarified the relationship between the chromatic properties of surface and the qualities on the dried lavers. The dried lavers had a high correlation between the grading and the chromatic properties of surface in the hue and luster values. Therefore, it was considered that the values of hue and luster can be used for the grading of dried lavers. A drying apparatus with the bar heater of far-infrared ray, was prepared for this experiment and the effects of the drying factors were analyzed. The surface temperatures of far-infrared heater and the air flow on the laver surface are the important factors for producing high quality lavers, and their combinations of drying conditions were clarified by this research.

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