不同光质对烟草组培苗生长及生理特性的影响

以‘云烟87号’生根组培苗为试材,以荧光灯为对照(CK),采用LED光源发射的单色光谱红光(R)、蓝光(B)、绿光(G)等不同光质配比组合光照处理,研究光质对烟草组培苗生长和生理特性的影响。结果显示:(1)与CK相比,红蓝绿(RBG)和红蓝白(RBW)组合光质使烟草组培苗植株株高、叶长、叶宽、叶面积、茎粗、根数、根长和干重显著增加,植株叶绿素含量也有提高但差异不显著。(2)RBW组合光质照射的植株可溶性糖含量和C/N比值显著高于其他光质处理,RBG组合光质处理植株的游离氨基酸含量显著高于其他光质处理,且各光质及其组合处理的烟草叶片可溶性蛋白含量显著高于对照,红蓝配光(1RB)使植株可溶性淀粉含量较对照显著提高。(3)各光质及其组合处理的烟草膜脂过氧化物MDA含量较对照均显著降低,而其SOD、POD和CAT活性较对照均显著提高;其中红光处理的植株膜脂过氧化物MDA含量最低,CAT活性最高。研究表明,LED光源不同光质及其组合光照均能够显著降低烟草组培苗的MDA含量,降低膜脂过氧化的伤害,促进烟草组培苗的生长,其主要通过调节抗氧化物酶活性的合成代谢来应对光氧化胁迫;LED光源的RBG和RBW组合光质可作为烟草组培苗生根阶段的最适光质。

Effect of Different Light Qualities on Physiological Characteristics and Growth of Tobacco in vitro under Light Emitting Diodes(LEDs)

By arraying tobacco rooted plantlets with the different wave length and ratio of light emitting diodes(LEDs),with fluorescent lamp(CK) light as control,the effects of light quality on physiological characteristics and growth were investigated.The results showed that:(1)Red-blue-green(RBG) and Red-blue-white(RBW) light enhanced the heights,leaf lengths and leaf widths,leaf area,shoot diameter,root length,number of root and dry weigh of plant,and the contents of chlorophyll were also up-graduated,but those of treatments were no significantly differences.(2)RBW light treatments led to higher content of soluble sugar and C/N ratio,RBG light treatments led to higher content of free amino acid,and significantly higher than that of other treatments;for all light treatments,tobacco leaf soluble protein content is significantly higher than that of CK light treatment,1Red-blue(1RB) light treatment led to higher content of soluble starch,and significantly higher than that of CK light treatment.(3)Fluorescent lamp(CK) light treatments led to higher contents of MDA,and significantly higher than that of other treatments;while decreased activities of SOD,CAT and POD in the leave,and significantly lower than those of other treatments;which red light lowered content of MDA and enhanced activity of POD,and CAT activity is the highest.LED light source can significantly reduce the MDA content of tobacco plantlets,reduce the membrane lipid peroxidation damage,promote the growth of tobacco plantlets,and the main reason lies in its regulation metabolism of the activities of antioxidant enzymes in response to photo-oxidative stress.