LED红蓝光质比对红叶石楠试管苗生长和抗氧化酶活性的影响

Effects of different light quality ratios of LED red/blue light on growth and antioxidant enzyme activities of Photinia fraseri plantlets in vitro

【目的】研究不同红蓝光质比LED对红叶石楠试管苗生长和抗氧化酶活性的影响,为高品质红叶石楠试管苗的生产提供理论依据。【方法】以红叶石楠试管苗为材料,采用LED光源的红光R(主波长640nm)和蓝光B(主波长464nm)设计5种不同光质配比(100%R、80%R+20%B、70%R+30%B、60%R+40%B、100%B),以普通荧光灯为对照(CK),探究不同光质比对红叶石楠试管苗形态指标、叶绿素、类胡萝卜素、根系活力、可溶性总糖、蔗糖、可溶性蛋白及抗氧化酶活性的影响。【结果】(1)红叶石楠试管苗株高、地下部鲜质量和干质量、总鲜质量在100%R处理下达到最大值;叶数、叶长、叶幅、地上部干物率、总干物率和类胡萝卜素含量在100%B处理下达到最大值;而根数、地上部鲜质量、地上部干质量和总干质量、地下部干物率、叶绿素a、叶绿素b、叶绿素总含量及根系活力在70%R+30%B处理下达到最大值。(2)各处理试管苗的可溶性糖、蔗糖和可溶性蛋白含量均以70%R+30%B处理最高。(3)叶片POD和SOD活性以70%R+30%B处理最高,CAT活性以100%R处理最高,MDA含量以80%R+20%B处理最高。【结论】红蓝光比为7∶3时有利于提高红叶石楠试管苗叶绿素、可溶性总糖、蔗糖、可溶性蛋白含量和根系活力及抗氧化酶活性,进而有效促进红叶石楠试管苗的生长,可以作为红叶石楠植物离体培养的最佳光质比。

【Objective】To provide theoretical basis for the production of high-quality Photinia fraseri plantlets in vitro,the effects of different light quality ratios of LED red/blue light on growth and antioxidant enzyme activities of P.fraseri plantlets in vitro were studied.【Method】Used the red light R(main wavelength 640 nm)and blue light B(main wavelength 464 nm)of LED light source,the P.fraseri plantlets in vitro were cultured under five different LED ratios(100%R,80%R+20%B,70%R+30%B,60%R+40%B,and 100%B)with ordinary fluorescent lamp as CK.Then,the effects of different treatments on morphology,chlorophyll content,carotenoids,root activity,soluble total sugar,sucrose,soluble protein and antioxidant enzyme activities of P.fraseri plantlets in vitro were explored.【Result】(1)The plant height,fresh and dry weight of underground part,and total fresh weight of P.fraseri plantlets in vitro reached maximum under 100%R.The leaf number,leaf length,leaf amplitude,dry matter rate and total dry matter rate of aboveground part,and carotenoid reached maximum under 100%B.The root number,fresh and dry weight of aboveground part,total dry weight,dry matter rate of underground part,chlorophyll a,chlorophyll b,chlorophyll content and root activity reached maximum under 70%R+30%B treatment.(2)The contents of soluble total sugar,sucrose and soluble protein were the highest under 70%R+30%B.(3)The activities of POD and SOD were the highest under 70%R+30%B,the activity of CAT was the highest under 100%R,while MDA content was the highest under 80%R+20%B.【Conclusion】The 70%R+30%B treatment was the best ratio of lightto improve the content of chlorophyll,soluble total sugar,sucrose and soluble protein and the activities of root and antioxidant enzymes in P.fraseri plantlets.