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The Seed setting in haploid plant of rice is rarely observed in general. The grains of 320 were obtained from the haploid plants of 773 derived by the anther culture. The grains of 294 germinated, and the grains of 261 grew up to the plants that were not haploid in appearence. Almost these plants had good fructification, and wese like diploidy. Only one plant, however, hardly fructificated. This reasons were concluded as follows : The natural doubling in the haploid plant of rice lead to the self-pollination by the diplontic gamate. The cross-pollination was originated in the pollen coming from the neighbouring plants.

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[in Japanese]

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[in Japanese]

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The effect of different plant densities on growth and yield components was investigated with using the cultivar Koshihikari in case of transplanting and direct planting cultures. Plant densities of transplanting were 30, 40 and 50 hills and those of direct planting 60, 80 and 100 hills per m^2. The time of additional fertilizer application to deeper layer was about 30 days before heading. Yields tended to increase at higher plant densities. Higher yields depended on increasing number of paddy rice per m^2. Moreover it was suggested to be necessary to increase number of paddy rice per ear rather than number of ear per m^2 owing to increasing number of paddy rice per m^2.

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"Shiranekomugi" is a soft red winter wheat develped in 1986 at the Nagano Agricultural Experiment Station. It was selected in the F_4 generation from the cross Hokuriku 49/Tokai 80 by bulk method. registered as Wheat Norin 131 by the Ministry of Agriculture, Forestry and Fisheries, and released as a recommended variety in Tochigi Prefecture in 1986 and Nagano Prefecture in 1987. Shiranekomugi has several good characteristics such as winter hardiness, lodging resistance, high yielding ability and good quality for making Japanese noodles.

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The experiments were conducted to investigate the relation among a sowing time of barlay (Hordeum vulgare L. cv. Minorimugi), its growth before a snow cover, and its snow endurance There was a close relation between the top dry matter weight just before the snow cover and the snow endurance of barley, which was measured by a ratio of alive stem numbers after/before the snow cover. When the top dry matter weight just before the snow cover was more than 0.5g, which were sowed before October 15, more than 30% of stem survived against 108 days of the snow cover. When it was less than 0.1g, which were sowed after Octorber 30, they could not survive. When it was between 0.08g and 0.57g, being sowed between October 15 and 30. the later sowing time, the lower snow endurance. And its snow endurance was highly and positively correlated with the top dry matter weight just before the snow cover, The top dry matter content just before the snow cover affected its snow endurance bo. The top dressing of nitrogen decreased the top dry matter content and its snow endurance. The lower top dry matter content, the lower snow endurance.

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[in Japanese]

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