亳菊试管嫁接苗褐变生理机制研究

Study on physiological mechanism of browning in vitro grafting of Dendranthema morifolium(Ramat.)Tzvel 'Boju'cv.Nov.

[目的]揭示亳菊试管微嫁接过程中组培苗发生褐变的生理机制。[方法]本研究以亳菊外植体为研究材料,使用福林酚法和多酚氧化酶活性测定法,对发生褐变的亳菊微嫁接苗总酚含量、多酚氧化酶活性以及褐变指数进行测定。[结果]亳菊微嫁接苗褐变级数越高,发生褐变的情况越严重,4级褐变率(89.7%)显著高于其他褐变级数;随着褐变级数的增大,亳菊试管微嫁接苗组织内总酚含量降低,多酚氧化酶活性增强,即褐变级数与外植体总酚含量成负相关,与多酚氧化酶活性成正相关。[结论]本研究为提高亳菊试管微嫁接效率提供了理论依据。

[Objective]To reveal the mechanism of browning in the process of micro-graft in vitro in Dendranthema morifolium （Ramat.） Tzvel ＇ Bojucv. Nov. [Methods]The Dendrantherna morifolium （Ramat.） Tzvel ＇ Boju＇ cv. Nov. was used as explant, and the total phenolic content, polyphenol oxidase activity and browning index of in vitro browned grafts were detected by Folin Method and Polyphenol oxidase Method. [Results]The results showed that with the increasing of browning series, the browning situation was more serious. The browning ratio of series 4（89.7%） was significantly greater than other browning series. The greater the browning series was, the total phenolic content was decreasing, meanwhile the polyphenol oxidase activity in the in vitro grafts was increased. There was a linear neg- ative correlation between the browning series and the explant total phenolic content, and there was a linear positive cor- relation between the browning series and the polyphenol oxidase activity. [Conclusion]This study providing the theory basis for increasing the efficiency of Dendranthema morifolium （Ramat.） Tzvel ＇Boju＇cv. Nov. in vitro grafts.