The effect of reduced light intensities i.e., 35, 50 and 70 per cent of normal sunlight (250-300 cal/day) on leaf chlorophyll content, photosynthesis and photorespi-ration was studied with two rice cultivars, Vijaya (shade tolerant) and IR. 8 (shade susceptible). The influence of blue and red light on photosynthesis of the above cultivars was also assessed. The results indicated that Vijaya was efficient under low light because of higher chlorophyll content mostly chl ‘b’ fraction, greater photosynthesis especially under blue light and lower photorespiration- In general, the efficiency in photosynthesis under blue light might indicate the relative adaptability of rice varieties to low light intensity.
