LED光质对蓝莓幼苗营养生长的影响

Effects of LED Spectral Composition on the Vegetative Growth of Blueberry Seedlings

摘要:

为探究培育蓝莓壮苗的适宜光质，以4月龄蓝莓幼苗为材料，设置CK对照(白光)、T₁(50%红光+50%蓝光)、T₂(60%红光+40%蓝光)、T₃(70%红光+30%蓝光)、T₄(75%红光+25%蓝光)、T₅(80%红光+20%蓝光)共6种光质处理，综合分析不同光质对蓝莓幼苗生长指标和光合特性的影响。结果表明，T₂、T₃处理显著增加蓝莓单株干重和壮苗指数；T₁、T₂处理能显著增加光合色素含量，T₂处理可溶性糖含量和根系活力显著增加。T₂、T₃处理的净光合速率、气孔传导率及蒸腾速率明显高于对照；胞间CO₂浓度随着红光比例升高而减小，其中T₁、T₂、T₃处理显著高于对照；T₄、T₅处理的水分利用效率显著增加。T₁处理的实际光化学量子效率和电子传递速率显著低于其他红蓝光组合，但与对照差异不显著；T₂、T₃处理的非光化学淬灭系数显著低于对照。综上，T₂处理通过增加光能利用速率、光合色素含量和气体交换参数，提升光合作用能力，产生较高含量的可溶性糖和可溶性蛋白，进而促进蓝莓干重的增加，有利于蓝莓壮苗的培育。

Abstract:

To identify a suitable LED spectral composition for producing high-quality blueberry seedlings, fourmonth-old blueberry seedlings were exposed to six light treatments: CK(white light control), T1(50% red light + 50% blue light), T2(60% red light + 40% blue light), T3(70% red light + 30% blue light), T4(75% red light + 25% blue light) and T5(80% red light + 20% blue light). The effects of the different spectral compositions on the growth traits and photosynthetic characteristics of the blueberry seedlings were comprehensively evaluated. The results showed that T2 and T3 significantly increased plant dry weight and the seedling quality index. T1 and T2 significantly increased photosynthetic pigment content, while T2 significantly increased soluble sugar content and root activity. The net photosynthetic rate, stomatal conductance and transpiration rate under T2 and T3 were significantly higher than those under CK. Intercellular CO₂ concentration decreased as the proportion of red light increased, but the values under T1, T2 and T3 were significantly higher than that under CK. T4 and T5 significantly increased water-use efficiency. The actual photochemical quantum yield and electron transport efficiency under T1 were significantly lower than those under the other red–blue light combinations, although neither differed significantly from CK. The non-photochemical quenching coefficients under T2 and T3 were significantly lower than that under CK. Overall, T2 enhanced photosynthetic capacity by increasing light-use efficiency, photosynthetic pigment content and gas-exchange parameters, thereby promoting the accumulation of soluble sugars and proteins and increasing seedling dry weight. Thus, the T2 treatment is beneficial for producing high-quality blue‐berry seedlings.