Adaptive Regulation of Photosynthesis in Rice Plant to Weak Light Condition and the Contribution of Root Activity to Regulation Mechanism

Japanese Journal of Crop Science

Yukindo TSUNO¹  Takeshi YAMAGUCHI¹ 

关键词: Dark respiration;    暗呼吸速度;    Dry matter production;    乾物生産量;    Nitrogen absorption;    光合成能力;    Photosynthesis;    遮光;    Rice plant;    水稲;    Root respiration;    窒素吸収量;    Shading;    根の呼吸速度;   

DOI  :  10.1626/jcs.58.74

学科分类：农业科学（综合）

来源: Nihon Sakumotsu Gakkai / Crop Science Society of Japan

【 摘 要 】

Three cultivars of rice plants were grown in pots in a shading frame of 50% light intensity and on shadowed place at high altitude of 303m in hillside during the different period from tillering to early ripening stage in order to compare the photosynthetic activity, root respiration and nitrogen absorption with those of control plants. After the period of tiller number determined, the shading-treatment promoted leaf area developing through the both ways of increase in leaf length and specific leaf area; it could contribute to enhancement of the photosynthesis per plant. Also photosynthetic rate per leaf area in the treated plant was higher than in the control plant due to higher N% in the leaf. Dry matter production was more depressed than nitrogen absorption by the shading, i.e., decreased rates of the former and the latter in average were 30.3% and 3.7%, respectively. The result of a multiple regression analysis for dark respiration of plant per leaf area (r^-) showed that r^- had a high positive correlation to N% in leaf and high negative correlation to C/F ratio (C: Stem weight, F: Leaf area), therefore, r^- of treated plants did not increase owing to the low C/F value. Multiple regression analysis between root respiration and two factors, N% in root and C/F ratio, showed high correlation coefficient as R=0.817**: the root respiration of the shaded plant had higher rate than that of control. The amount of nitrogen absorbed during treated period was sustained with the root respiration and the dry matter production.

【 授权许可】

Unknown