Studies on the Effect of the Relative Humidity of the Atmosphere on the Growth and Physiology of Rice Plants : Effects of ambient humidity in the dark period on the growth and the translocation of 13C-labelled photosynthetic products

Japanese Journal of Crop Science

Genichi HIRAI¹  Shiro TAKEUCHI¹  Hiroyoshi CHUJO¹  Osamu TANAKA¹  Toshikatsu OKUMURA¹ 

关键词: ^13CO2 feeding study;    暗条件;    Photosynthetic product;    光合成産物の転流;    Relative humidity;    光合成量;    Rice;    重炭素トレーサ法;    Translocation.;    水稲;    大気湿度.;   

DOI  :  10.1626/jcs.67.216

学科分类：农业科学（综合）

来源: Nihon Sakumotsu Gakkai / Crop Science Society of Japan

【 摘 要 】

Rice seedlings(age in leaf number of 3)were grown for 10 days at 75% relative humidity in the light period(12-hr)and at 60, 75, or 90% humidity in the dark period(12-hr)Dry matter production of the plants grown under higher humidity in the dark period was higher than that of the plants grown under lower humidity.High humidity in the dark period also increased the leaf area, heightened the plant length and accelerated leaf emergence.Then, the effects of humidity in the dark period on the 13C-labelled CO2 assimilation, translocation of 13C-labelled photosynthetic products, water content and respiration were examined.The amount of 13C assimilated by plants grown under high humidity in the dark period was greater than that by plants grown under low humidity in the dark period.High humidity in the dark period brought about a greater transfer of 13C-labelled photosynthetic product to the youngest(late-emerging)leaf than low humidity.High humidity in the dark period also induced an increase in water content, which resulted in the promotion of photosynthesis.Respiration in the dark was not influenced by humidity.Therefore, the promotion of increased leaf area, increased plant height and accelerated leaf emergence, which were observed in plants grown under high humidity in the dark period, is due to increased photosynthesis and the translocation of photosynthetic product to the late-emerging leaves in the plants.These results indicate that humidity in the dark period plays an important role in the growth and development of rice seedlings.

【 授权许可】

Unknown