剑麻不定芽玻璃化过程中的细胞学和生理变化研究

Cytological and Physiological Changes During Hyperhydricity in the Culture of Adventitious Shoots of H.11648

玻璃化问题是植物组织培养过程中的普遍现象,已成为植物组织快速繁殖的瓶颈。本研究以H.11648为材料,分析H.11648不定芽玻璃化过程中气孔形态、DNA含量、叶片含水量、可溶性蛋白含量、丙二醛(MDA)含量以及过氧化氢酶(CAT)、过氧化物酶(POD)、抗坏血酸过氧化物酶(APX)和超氧化物歧化酶(SOD)等防御酶活性变化情况,结果表明:玻璃化后的不定芽叶片保卫细胞膨大,气孔变大。体细胞DNA含量没有变化,但细胞数减少。随着玻璃化程度的增加,叶片含水量显著增加,可溶性蛋白和丙二醛含量明显降低,POD活性显著上升,SOD活性先上升后又略有下降,但均显著高于正常水平,APX活性先明显上升后又恢复到正常水平,CAT活性略有下降但不显著。本研究为揭示剑麻不定芽玻璃化的生理机制提供参考。

Hyperhydricity is a serious problem during in vitro culture of plant, and it is considered as a bottleneck to micropropagation of plants. Stomata form and DNA content, water content, concentrations of soluble protein and malonyldialdehyde, the activities of antioxidative enzymes, e.g. peroxidase（POD）, catalase（CAT）, ascorbate peroxidase（APX） and superoxide dismutase（SOD）, were examined in adventitious shoots of H.11648. The results showed that guard cell expanded and the pore surrounded by the guard cues in hyperhydric leaves were more rounded in contrast to the elliptical pore in normal leaves. The DNA content was not changed while cell number decreased after hyperhydriciting.Hyperhydric shoots had higher water content, lower soluble protein and MDA concentration than normal shoots.The activities of antioxidant enzymes, such as POD and SOD significantly increased in hyperhydric shoots than in healthy shoots. CAT showed a slight decrease in activity in the hyperhydric leaves than in healthy leaves, APX activity significantly increased at H1 stage and then recovered normal levels at H2 stage. The results would provide a reference for revealing the physiological mechnism of hyperhydricity of adventitious shoots of H.11648.