LED光质对油茶苗生长和光合特性的影响

目的]探寻适合油茶苗培育的最佳LED光质配比。方法]以2年生长林4号油茶扦插苗为试材,LED白光为对照,研究LED红光、蓝光及其复合光对油茶苗生长和光合特性的影响。结果]表明:L1(红光)处理下,油茶苗高生长量最大,但表观量子效率、光补偿点和胞间CO2浓度最小;L7(蓝光)处理下,油茶苗光补偿点最高,但高生长量、干物质含量、壮苗指数、气孔导度和蒸腾速率最小;L6(10%红光+90%蓝光)处理下,油茶苗地径生长量、干物质含量、壮苗指数、光合色素含量、表观量子效率、最大净光合速率、暗呼吸速率、气孔导度、蒸腾速率、实际光能转换效率和相对电子传递速率均最大;L4(50%红光+50%蓝光)处理下,油茶苗地径生长量、光合色素含量、最大净光合速率、实际光化学效率和相对电子传递速率均最小,且非光化学淬灭系数最大。结论]与对照及其它处理相比,L6(10%红光+90%蓝光)处理更利于长林4号油茶苗生长和光合能力的提高,是培育油茶壮苗较为理想的光质。

Effects of Light Qualities on Growth and Photosynthetic Characteristics of Camellia oleifera Cutting Stocks

Objective] To find the best combination of LED light quality for Camellia oleifera cutting stock. Method] Effects of red LED, blue LED and their composite light on the growth and photosynthetic characteristics of C. oleifera were studied taking two-years-old cutting stocks of Changlin-4 C. oleifera as test materials and white LED as control. Result] Under the irradiation of L1 (red light), the height increment of C. oleifera stocks was the highest, but the apparent quantum efficiency, light compensation point and intercellular CO₂ concentration were the lowest. Treated with L7 (blue light), the C. oleifera stocks had the highest light compensation point, and the lowest height increment, dry matter content, sound stock index, stomatal conductance and transpiration rate. The diameter increment, dry matter content, sound stock index, photosynthetic pigment content, apparent quantum efficiency, maximum net photosynthetic rate, respiration rate, stomatal conductance, transpiration rate, light energy conversion efficiency and relative electron transport rate of C. oleifera were the highest under the irradiation of L6 (10% red lights+90% blue lights). While the diameter increment, photosynthetic pigment content, maximum net photosynthetic rate, light energy conversion efficiency and relative electron transfer rate of which all were the lowest with the treatment of L4 (50% red lights+50% blue lights), furthermore, the non photochemical quenching coefficient was the highest. Conclusion] Compared with the control and other treatments, L6 (10% red lights+90% blue lights) is the ideal light quality to cultivate sound cutting stocks of C. oleifera, which is more conducive to the growth and photosynthetic capacity of Changlin-4 C. oleifera stocks.