Effects of Night Illumination on the Growth of Rice
Twenty rice (Oryza sativa) cultivars in Taiwan were used to study the effect of night supplemental lighting, using high pressure sodium lamp and mercury lamp as light sources, on the growth and heading time. Results showed that night illumination affected plant growth and development. Light supplement in the dark period extended the days required for heading, and photo-sensitivity more obvious in the second crop season than that in the first crop season, and the effects of high pressure sodium lamp on extending heading date was stronger than mercury lamp. The response of growth and heading time to night lighting were significantly different among all test entity. Similar results were found in plant height, leaf number and the upper three leave lengths. Results obtained from this study might provide some useful information for farmers to select suitable cultivars to meet the demand in special cultivated condition.
Key words：Rice, Cultivar, Night illumination,
Accepted for publication:May 9,2011