银杏种子后熟生理与内源激素变化的研究

Study on the After-Ripening Physiology and Endogenous Hormones of Ginkgo biloba Seeds

研究银杏种子后熟期间的生理变化以及内源激素对种子休眠与萌发过程的调控作用。结果表明:银杏种胚分化不完全、发育不充分是种子休眠的主要原因,银杏种子的后熟过程实质上是种胚不断分化生长的过程。在此过程中,物质代谢、酶活性的变化均有利于种胚发育和种子发芽,种子内部经历了一系列生理生化变化去调整内源激素平衡、完成种胚发育。研究发现,内源激素在银杏种子休眠与萌发过程中起着重要的作用:GA1+3是银杏种胚后熟的关键物质;ZRs对银杏种子生长起重要的促进作用;GA1+3ABA及ZRsABA相对比例的变化对种子发育、胚的后熟及种子萌发均有重要的影响。

The after-ripening physiology and roles of endogenous hormones of Ginkgo （ Ginkgo biloba） seeds were studied in this paper. The results showed that seed embryo uncompleted differentiation and uncompleted development were the main reasons for Ginkgo seeds dormancy; the after-ripening was a process of embryo differentiation and growth of Ginkgo seeds. After morphological ripening, the seeds must go through a series of physiological and biochemical changes in order to finish embryo development and endogenous hormones balances. Some plant endogenous hormones such as ABA, GA and ZRs acted an important role in the every stage of seed dormancy and germination. GA1 ＋ 3 had a decisive role during dormancy and germination of Ginkgo seeds. ZRs could induce the growth of fruits, but was not the necessitate factor of dormancy and germination. The relative ratio of GA1＋3/ABA and ZRs/ABA may play a more important role than their absolute level during the seed development and embryo after-ripening.