木芙蓉花期不同阶段主要器官内源激素含量的变化

Changes of Endogenous Hormone Content in Main Organs of Hibiscus mutabilis Linn During The Flowering Period

为探索非自然方式调控木芙蓉花期的机理,以木芙蓉品种‘锦绣紫’为试验材料,在木芙蓉花芽分化期、花芽分化后期、花蕾期、初花期、盛花期、盛花末期、二次盛花期和末花期采集对应的叶片、花蕾、盛开花和衰败花,采用高效液相色谱法和气谱法检测吲哚乙酸(IAA)、赤霉素(GA_(3))、脱落酸(ABA)、细胞分裂素(CTK)和乙烯(ETH)5种内源激素的含量变化。结果显示,本研究的高效液相色谱法和气谱法检测条件可靠,能够准确检测木芙蓉叶、花中5种内源激素的含量。在花芽分化期,叶片中CTK含量最高,GA_(3)、ABA含量较高,IAA含量最低;花芽分化后期,叶片中GA_(3)、CTK和ABA含量快速降低。在初花期,各器官中IAA处于较高水平,其他内源激素均处于较低水平。随花期推进,花蕾、盛开花、衰败花中内源激素水平变化较大,主要表现为ABA含量高于其余激素;在二次盛花期以后,叶片与花的内源激素变化趋于一致,亦表现出ABA含量最高。木芙蓉‘锦绣紫’有二次盛花的特性,各器官内源激素水平随花期波动变化,ABA含量变幅最大,ETH含量较为稳定。可得结论,在花芽分化期,叶片中较高含量的CTK、GA_(3)和ABA可促进花芽分化;初花期以后,叶片和花中较高含量的GA_(3)、ABA、ETH可促进木芙蓉开花,加速花的衰败。本研究结果可为非自然方式调控花期提供参考。

A Hibiscus mutabilis Linn designated as‘Jinxiuzi’was chosen as the experimental material.The leaves,flower buds,blooming flowers and withered flowers were collected at the flower bud differentiation stage,late flower bud differentiation stage,bud stage,initial flowering stage,full flowering stage,late flowering stage,second full flowering stage and last flowering stage.The contents of IAA,GA_(3),ABA,CTK and ETH were determined by high performance liquid chromatography(HPLC)and gas chromatography(GC).The results showed that the detection conditions of HPLC and GC were reliable,and could accurately detect the contents of the five endogenous hormones in leaves and flowers of Hibiscus mutabilis.At the flower bud differentiation stage,CTK content was the highest,GA_(3) and ABA content was higher,and IAA content was the lowest.At the late flower bud differentiation stage,GA_(3),CTK and ABA content in leaves decreased rapidly.At the initial flowering stage,endogenous hormone levels in all organs were low,while IAA was highest.With the advance of flowering stage,the endogenous hormone levels in buds,blooming flowers and withered flowers changed greatly,mainly manifested in higher ABA content than other hormones.After the second full flowering stage,the changes of endogenous hormones in leaves and flowers tended to be consistent,and ABA content was the highest.With the characteristic of secondary flowering,the levels of endogenous hormones in leaves and flowers of H.mutabilis Linn.‘Jinxiuzi’fluctuated greatly during the whole flowering period.The ABA contents changed sharply,and the ETH contents were relatively stable.In general,higher concentrations of CTK,GA_(3) and ABA in leaves promoted flower bud differentiation during flower bud differentiation;after the initial flowering stage,the higher content of GA_(3),ABA and ETH in leaves and flowers could promote Hibiscus mutabilis Linn flowering and accelerate the decline of flowers.The results can provide a theoretical reference for non-natural regulation of flowering time.