摘要
苜蓿叶柄在Ｂ５Ｈ培养基上诱导并继代所形成的是无色、松软的胚性愈伤组织，内含许多有分生能力的细胞团。当Ｂ５Ｈ中的ＫＴ用ＴＤＺ替换时，愈伤组织变绿变硬，出现管状分子和芽原基的分化，其体胚发生能力丧失，而且其乙烯生成和ＰＡＬ活性升高。乙烯形成酶的抑制剂ＣｏＣｌ２可以抑制ＴＤＺ的上述作用，部分地恢复愈伤组织的体胚发生能力。ＴＤＺ对愈伤组织的这些作用可能与其促进乙烯生成有关。
Callus initiation from the petiole,induction and development of the somatic embryos occurred in medium B5H, B5g and SH (hormone--free )with proline 30 mmol/L and (NH4 )2SO4 10 mmol/L respectively.When kinetin in B5H was replaced by TDZ, the colorless, friable and embryogenic callus in B5H become green,campact and nonembryogenic. TDZ increased ethylene production and PAL activity of the callus 3 to 4--fold and 2 fold, respectively, after 3 to 4 week culture. Histological observation revealed that some tracheary elements and their strands were differentiated from the callus with TDZ, but meristem-like structure from control callus.CoCl2, an inhibitor of ethylene forming--enzyme, was found to countereact to the effects of TDZ and the effects of CoCl2 depend on its concentration. The callus can be changedback colorless, friable one, and its capability of undergoing somatic embryogenesis recovered to some extent, but its ethylene production was reduced, or even stopped, by treatment with CoClz2 These results indicated that in this culture system TDZ may favor differentiation of tracheary element and bud formation, but inhibit somatic embryogenesis. The effects of TDZ may involve ethylene biosynthesis.
基金
国家自然科学基金
关键词
苜蓿
愈伤组织
体细胞胚胎发生
乙烯
TDZ
Callus of Alfalfa, somatic embryogenesis, ethylene, phenylalanine ammonia-lyase (PAL), CoCl_2, Thidiazuron
