Using the data of determining test of recommended variety of rice, the author tried to classify the plain part of baisin area in Yamagata prefecture into several groups from the yield of variety cline. Result of this investigation is following 1. The coefficient of rank correlation, the repeatability and the interaction of VP were applied to the yields data, however 10 places could not be classified clearly by those statistical methods. 2. Generally, this is due to the fact that the yield of variety (line) is very variable, by place and year, and the relative yield of variety is remarkably instability. 3. On the breeding area, it will be necessary to consider about both the point of yield and the ecological point.

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Each one clone of orchadgraes, perennial ryegrass and timothy was grown under some combination of air-and soil-temperatures. Greatest growth, in terms of dry matter production, plant height, leaf number, leaf size and tiller number, was obtained under 17-24°C and 24-17°C conditions associated with less DM% and less LB/LS+stem ratio. It may be effective for the promotion of growth to raise or drop soil-temperature by some managemental way when air-temperature is unfavorable for the growth.

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Plant height and no. of leaves of main-stem were progressivly greater as the temperature raised except the no. of branches which was less affected by the treatments. In general, the growth in terms of plant height, no. of branches, no. and size of leaves, and fresh- and dry-matter production was promoted by lowering or raising soil-temperature when air-temperature was higher or lower than the optimum, respectively. The greatest growth was obtained in both legumes under 28°-20°C and 23°-17°C coditions.

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The following results were obtained from the experiments to get high yield on sugar beet cultivation carried out at Furumaki Branch, Aomori Agricultural Experiment Station from 1962 to 1967. 1) The yield increased by transplanting cultivation was on or about 15% increase than that of direct sowing, though its effec iveness were subjected to change slightly by the yearly differences of climate. 2) The effectiveness of soil improvement by the heavy dose of phosphate (as applied by the shape of fused phosphate) was about 10 to 20% increase of the yield. The yield of sugar beet was closely correlated with the amount of exchangeable base and saturation degree of cation exchange capacity of the soil. 3) New varieties of "Tsukisappu", "E-5" and "Polyrave" gave higher yield about 10 to 15% than that of existing variety of "Donyu No.2". 4) By the combination of about mentioned facts, the yield of sugar beet increaser more than 55 tonnes per hectar and it was higher about 40% than that of direct sowing of "Donyu No. 2".

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