Studies on the Effect of the Relative Humidity of the Atmosphere on the Growth and Physiology of Rice Plants : VIII. Effect of ambient humidity on dry matter production and nitrogen absorption at various temperatures

[摘要] The effect of relative humidity (RH) on the dry matter production and nitrogen absorption of rice seedlings (age in leaf mumber of 5) was investigated. Plants were grown for 4 days under 60 or 90% RH at 12-hr day/12-hr night temperatures of 24/20, 28/24, 32/28 and 36/32°C. 1. Dry matter increase of leaves and roots in the plants grown at 90% RH was higher at 24/20 and 28/24°C, but lower at 32/28 and 36/32°C than that of the plants grown in 60% RH. 2. Nitrogen absorption and content of heavy nitrogen of leaves and roots in the plants grown at 90% RH were also higher at 24/20 and 28/24°C, but lower at 32/28 and 36/32°C than those of the plants grown in 60% RH. These results indicate that dry matter increase and nitrogen absorption of rice seedlings are affected by humidity and temperature, with highly significant correlations.

[学科分类] 农业科学（综合）

[关键词] Dry matter production;乾物増加量;Heavy nitrogen;水稲;Nitrogen absorption;相対湿度;Relative humidity;窒素吸収;Rice.;標識窒素.