光质与补光对水稻幼苗生长及光合速率的影响

测定水稻成龄离体叶片在波长380～800nm下的透射率,推算其吸收光谱;在培养室内,观测水稻幼苗在蓝(475±5nm)、黄(585±5nm)、红(660±5nm)色的半导体(LED)和普通日光灯下的生长状况,每天照光12h;同时,在大棚中将刚萌发的水稻幼苗白天自然日照,每晚(18:00～24:00)人工补蓝、红、黄、白光各0、2、4、6h,定期观测其生长情况,在补光50d后测成龄叶片的光合曲线。结果发现:水稻叶片在波长400～500nm之间及680nm附近有较强吸收;在不同光质下进行培养,单波蓝光对水稻幼苗的生长最好;补光对水稻幼苗生长均有促进作用,其中补白光4h效果最明显,其次是补黄光2h;补蓝光2、4h和补白光4h提高植株的光合能力。

Effects of different light quanlities and illumination supplement on growth and photosynthetic rate of rice seedling

The transmissivity of rice leaf under the wavelength of 380～800 nm were measured to reckon the absorb-spectrum. And rice seedlings were cultured under 12 h of continuous illumination with blue light (475±5 nm),yellow light (585±5 nm),red light (660±5 nm) and white light everyday. Meanwhile,the lights were extraordinarily offered to rice seedlings grown under natural conditions in daylight, metering the dynamic growth of the plants during this time and measuring the photosynthetic rates and curves with Li-6400 50 days later. The results showed that the light with wavelength of 400～500 nm or 680 nm was absorbed stronger by rice leaves. When growing under light with different qualities, the seedlings treated by blue light were much stronger than the others. Growth of rice seedlings was obviously enhanced by illumination supplements. Healthy index of seedlings treated by white light 4 h/day was maximal, and the yellow light 2 h/day treatment was the second. In addition,the photosynthetic rates of the blue light 2 h/day treatment,the blue light 4 h/day treatment and the white light 4 h/day treatment were improved.