Rice Seeds Coated with the Calper were sown in the soil filled in a plastic container. A part of nitrogenous fertilizer was top dressed at different growing stages. The top dressing started from 2 months prior to the expected heading date at 5 day intervals.
The following conclusions were drawn from this experiment:
1) The maximum weight of paddy was obtained from a treatment with an application of top dressing 33 days prior to the heading date.
2) The maximum number of grains per panicle was obtained from a treatment with an application of top dressing 28 day prior to the heading date.
3) The more, lengthes of panicle, stem and leaf, the more, the number of grains per panicle.
4) The number of grains per panicle can be roughly estimated from the distribution density of the number of greater than 90 grains per panicle and less than 40 grains per panicle.
5) The stem density (Kanchomitudo) which is defined as the total length of stem of rice plant populated in unit area can be used as a parameter effective to yield prediction after heading.

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To improve the working environment of farmers, the spray test of liquid pesticide was made in a testing greenhouse. TPN (75% wettable powder) diluted 800-fold was sprayed under the various spray conditions, and the change of aerial concentration and sticking amount to a filter paper were measured.
And the generation amount of secondary droplets which generate from the target was also measured.
The experimental results are summarized as follows.
1. The aerial concentration increased with the rise of spray pressure, and this increase greatly depended on the increase of coarse particles more than7μm.
2. The humidity in the greenhouse greatly influenced the aerial concentration. When the pesticide was sprayed in a high humidity atmosphere, the aerial concentration become smaller because of the evident decrease of respirable particles less than 7μm.
3. The sticking amount increased with the spray pressure rise.
4. The generation amount of secondary droplets increased linearly with the spray pressure rise. However, with the increase of nozzle number and low pressure spray, the generation amount could be obviously decreased without reduction of the flow rate. The generation rates of secondary droplets were 13-20%. On the basis of this result, it was proved that about 20% of pesticide sprayed in a cultivating field scatters in the air.

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The research study was intended to clarify the actual situation of pesticide exposure of farmers following citrus fruit cultivation in greenhouse. The aerial concentration and the dermal exposure amount were measured for Kelthane, Salithion, and DMTP sprayed by power sprayer. These were 33%, 25%, and 40% wettable powder respectively. The cycle of pesticide spraying, the sorts of pesticides, and the working hours in greenhouse were also investigated.
It was summarized as follows;
1. The aerial concentration around the operator was estimated a little small. And that was about 30μg/m³ for Kelthane whose available component was diluted 3030-fold, and about 140μg/m³ for 4000-fold diluted Salithion. The evaporability of Salithion was remarkable, and its aerial concentration was considerably higher than that of others during spraying and after.
2. The dermal exposure amount was verry large. This exposure amount at face was about 0.05μg/cm²·min for 3030-fold diluted Kelthane and about 0.02μg/cm²·min for 3800-4000-fold diluted Salithion or DMTP.
3. Pesticide was sprayed once a month, and the total number of spraying was 5-7 through eight months cultivation. About 10 kinds of pesticide were used. The working hours in greenhouse was about 10 hours per ten ares in ten days for a man and about 3 hours for a woman. Compared with a case of vegetable cultivation, this working hours was so small that the exposure to pesticide residues was estimated verry small.

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A solid manure injection system is a benifical method which reduces undesirable order and pollution problems from runoff. This system design consists of two basic units which are furrow opener and auger conveyer of manure.
The manure tested first on the auger unit was bark of broadleaved tree. This material did not work into auger unit easily by stopping at the feed inlet port of auger unit. To solve this problem the tests were trid with lieqid (moisture content 78%) and dry (moisture content 13%) conditions of bark manure.
The test results were as follows:
(1) The bark manure on dry condition could not allow the revolution speed of auger shaft to work when the area of feed inlet port of auger unit was relatively small and the revolution speed of auger shaft was relatively high.
(2) The injection volume of manure on liqid condition was much as compared with dry condtion on the same revolution speed and angle of auger shaft, but poor in the ingredient of mamure, because of water content of 78%.
(3) The required torque of auger shaft on liqid condtion of manure was large with large revolution speed. The manure of liqid condition was dropped down by itself on 60° in the angle of auger shaft. Therefore, it was hard to control the volume of manure by the revolution of auger shaft.
(4) The injection volume per required torque of auger shaft on liquied condition of manure, was much as compared with dry condition when the revolution speed and the angle of auger shaft were relatively small, and was less when they were large, The efficiency of injector was high on liqid condition when the area of feed inlet port was relatively small.
(5) The solid manure injector that was attached the auger conveyer to furrow opener of shovel with the angle of 45° from above results, was tried to test on field. From the results, it could easily cotrol the injection volume of manure by changing the revolution speed of auger shaft.
In realization, 2 or 3 drills of this device will be located at the front end of a box type manure spreader, in which the travel drection of the web will be reversed to bring the manure to the front. The device should inject the manure at a spacing which corresponds to row crop spacing and if it could use at the same time with seeding divice, a considerable reduction of production cost would be realized.

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We analysed the both direct and indirect energy input to the field with the data of fuel consumption and crop yield from a serial experiments on successive no-tillage farming for seven years.
1) The average yield of dent corn in no-tillage plot(NT) was about 88% of that in conventional tillage plot(CT). The yield of turnip in NT was almost as same as that in CT. The both yield of barley and wheat in NT after six years were extreamly poorer then those in CT.
2) From the yieid of dent corn, the duration of six years was thought as practical successive limits in no-tillage farming.
3) The ratio of energy output/direct energy input was calculated with the yield obtained from our experiments for seven years. The average ratio for three crops in NT were 2-3 times as large as those in CT.
4) As production energy of herbicide was generally large, energy input in NT was equivalent to 64% of that in CT for the processes before seeding, and 84% of that in CT for all processes, respectively.
The difference of energy input between CT and NT including both direct and indirect energy was smaller than that including direct energy only.

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