Growth response and carbohydrate changes in rice seedlings exposed to supplemental UV-B radiation

摘要

The effects of UV-B (0.7Wm~(-2 )) radiation on growth response and leaf carbohydrate mobilization were evaluated in the two rice seedlings (cvs. Woonjangbyeo and Ilpumbyeo)(Fig.2). Immediately after UV-B treatment, the increase of dry matter and leaf area was negatively influenced(Fig.1). Individual growth characteristics including RGR, SLW and SLA were calculated at before and after UV-B treatment. Under without UV-B condition, RGR in cvs. Woonjangbyeo and Ilpumbyeo increased two- and three-fold over that in with-UV-B condition, respectively, SLW and SLA, however, did not show significant differences. After UV-B treatment, leaf soluble sugar in each plant part (cv. Woonjangbyeo) was monitored for several days. In all parts (leaf blade, leaf sheath and growing leaf), soluble sugar contents decreased 3- to 5-fold during UV-B radiation.