In this study we practiced a joint experiment on tillage methods (PT, RT and NT) and soil types (volcanic L, volcanic SiC and sandy LS) simultaneously throughout the three places (Tokyo, Niiga taand shimane) from April in 1988 to June in 1991. In this paper we report the experimental results on six croppings for three years (crops=dent corn in summer and barley in winter) at volcanic L soil.
1) Significant differences of the grain yield of dent corn were not observed in plots at the third and fifth croppings though they didn't reach to an ordinary yield level because of damages by tornado and hail. The grain yield of barley of NT was the maximum in plots at the second cropping, but it decreased at fourth cropping. It decreased more sharply at the sixth cropping. There were no differences in harvest index of the plots.
2) The quantity of weed of NT at the fourth and sixth croppings were more than those of PT and RT. The dominant species of weed were commonly observed in the plots.
3) Significant differences of soil hardness (penetrating resistance) were observed in depth and plots. Soil hardness of NT were higher than other plots because of passed an half year from the final tillage. In the results of soil hardness changes during one cropping, the hardness of PT and RT increased after one month from the final tillage.
4) Significant differences of soil pH were not observed in depth and plots.
5) From the viewpoint of crop yield, no-tillage farming is profitable to the early cropping, so a renewing tillage to NT become to be important in practical.

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In this study, the authors practiced a joint experiment on tillage methods (PT·RT·NT) and soil types (volcanic L·sandy LS·volcanic SiC) simultaneously at the three places (Tokyo·Shimane·Niigata) from 1988. In this paper, we arranged the experimental results on six croppings at the three places for three years (crops=dent corn in summer and barley in winter), and discussed the adaptability and problems to a practical field in general.
1) Emergence percentage of NT in dent corn was low at all places, but the tendency in barley was different from that in dent corn. In NT, the problem of covering seeds with soil at planting was important.
2) The grain yield in both croppings of dent corn and barley at Tokyo was the highest among the places, but the yield at Shimane was the lowest. There were no differences in dent corn among the plots. In barley, the yield of RT was 97% of that of PT, and the yield of NT was 81% of that of PT. On an average in the places, the yield of barley of NT were the lowest among the plots.
3) In dent corn, the quantity of weed was the most at Tokyo among the places, and that of NT was the most among the plots. In barley, the quantity of weed at Niigata was the most among the places, and that of NT at Tokyo and that of RT at Niigata were the most among the plots.
4) The highest soil hardness (average penetrating resistance in all tested soil layers) was in NT, the middle was in RT and the lowest was in PT. The value at Shimane increased rapidly.
5) In soil three phases, the highest portions were an air% at Tokyo, a liquid% at Niigata and a solid% at Shimane.
6) No-tillage farming had the conspicuous reducing effects on direct energy and labor consumption. Judging from these results, to acquire the effect on advancing a planting date as 10-12 hours per hectare was not difficult by no-tillage farming.
7) We discussed the problem remained in a practical field.

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In this study we practiced a joint experiment on tillage methods (PT, RT and NT) and soil types (volcanic L, volcanic SiC and sandy LS) simultaneously throughout the three places (Tokyo, Niigata and Shimane) from April in 1988 to June in 1991. In this paper we report the experimental results on six cropping for three years (crops=dent corn in summer and barley in winter) at volcanic SiC soil.
1) The emergence rate of NT was higher than other plots, and the rate of RT was lower at barley of fourth cropping. At dent corn of fifth cropping, there was no difference of emergence rate on the field between PT and RT, and the rate of NT was lower excessively than other plots.
2) Significant differences of the grain yield of dent corn were not observed in plots at the third cropping. The grain yield of barley decreased annually in every plots, but the rate of yield reduction of NT was the minimum among three plots. Significant differences of the grain yield among all plots were observed at the sixth cropping.
3) The quantity of weed of NT at the sixth cropping was smaller than those of PT and RT.
4) Significant differences of soil hardness (penetrating resistance) were observed in depth and plots. Soil hardness of NT were higher than other plots because of passed four months from the final tillage. In the results of soil hardness changes during one cropping, the hardness of RT approached the level of NT in depth of 20-30cm after two months from the final tillage, but the hardness of PT kept the effect of tillage untill each harvest.
5) No-tillage farming in continuous barley production at volcanic SiC soil was thought to be an effective system because of higher rate of emergence.

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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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In this study, we practiced a renovation trial by plowing to the continuous no-tillage field passed 11 years. The field seemed to be deteriorated for cultivation judging from the changes of soil condition and crop yield. The renovation trial based on the two-factors experiment with three levels of tillage and three levels of materials for soil improvement was started at April in 1991.
1) Water content of soil in NC (renovation of notillage plot) was equal to that in CC (continuous plowing plot), but soil hardness (penetration resistance) in NC was higher than that in CC.
2) Field efficiency of plowing in NC was higher than that in CC. Depth of tillage in NC was equal to that in CC, but the average value of width of tillage estimated from total width of plowed area and number of furrow in NC was wider than that in CC.
3) Fuel consumption per unit area in NC was 5% higher, and the consumption per unit time in NC was 14% higher than those in CC.
4) Specific resistance of soil estimated from the measured values, such as fuel consumption and traveling speed, in NC was higher by 8% than that in CC.
5) From the result of analysis of variance for dry matter yield of corn, there was the significant difference with 1% level for tillage factor only. When we adopted the value of 100 to crop yield in CC as a standard, the crop yield in NC was 97, that was 67 in NN (continuous no-tillage plot), respectively.
6) From the result of analysis of variance for the quantity of weed, there was the significant difference with 5% level for the tillage factor only. The quantity of weed in NN was much than any other plots.
7) In NN, notable pH drop was observed at the soil layer of 5-10cm in depth. The pH profile in NN at the layer of 0-20cm approached to that in CC which showed an uniform distribution of pH.
8) In spite of the deteriorated field by continuous no-tillage farming for 11 years, the crop yield almost recovered to the yield level in CC by only once tillage as a renovation.

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伝熱型熱量計により, 数種の食品固形成分および水分を含む玄米の比熱とエンタルピを測定した。固形成分の比熱は一般に温度の上昇に伴い微増する傾向がみられた。玄米については, 0～25%wbの水分範囲で, -20～20℃の温度範囲でエンタルピ-水分線図を作成した。

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This paper investigated the saving effect on direct energy input (consumed fuel) from a serial experiments of no-tillage farming (NT) and a conventional tillage farming (CT) for seven years.
1) The NT saved direct energy input per unit area (Ea) of 49% in dent corn, 69% in feed turnip and 61% in barley and wheat in comparison with the CT because of omitting both plowing and harrowing.
2) The order of Ea in the CT were harvesting>plowing>disk harrowing in dent corn, plowing>loading and carrying>disk harrowing in feed turnip, plowing>harvesting>disk harrowing in barley and wheat, so both plowing and harvesting required a lot of energy in the all operations.
3) Disk harrowing required the most energy per unit time (Et) in the all operations.
4) If the estimation of Ea and Et allows the error within 10% in seeding and fertilizing, energy calculation can used the same values of Ea and Et for both CT and NT.
5) We estimated the turning points of profit and loss in energy balance with the everage yield of two crops published in Japan. If the NT attain the only 45% of CT yield in dent corn and the only 33% of CT yield in wheat, the output/input ratio of direct energy in NT was equivalent to that in CT from the result of estimation.

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