| 摘要: |
| 【目的】探索温度与西红花花芽分化的关系，以及顶芽中内源激素随温度变化的动态变化，为制定西红花开花期间的室内环境条件标准化方案奠定基础。【方法】以西红花球茎为材料，观测顶芽在自然温度和恒温（15，20，25和30 ℃）条件下的花芽分化进程、花芽分化比例等，测定花芽分化进程中内源激素IAA、IBA和GA3含量的变化。【结果】自然温度下，花芽分化时间从7月下旬至9月上旬，整个分化过程持续45~50 d，属于向心型发育；在25 ℃恒温下，花芽分化时间从7月中旬至8月中旬，历经30~40 d。同时，在15 ℃和30 ℃下没有花芽分化，在20和25 ℃下，花芽分化的比例分别为55%和96%。ABA和IAA含量从休眠期至花芽分化初期持续降低，花芽分化期略有升高，且花芽中的ABA和IAA含量低于叶芽。GA3含量从休眠期至雄蕊分化期持续升高，之后略有降低，且花芽中的GA3含量高于叶芽。同时，在花芽分化期ABA/GA3、IAA/GA3保持低水平，花芽低于叶芽，但均呈整体下降趋势。叶芽中ABA/IAA在顶芽分化前升高，之后降低;而花芽中在分化初期降低，分化过程中略有升高。【结论】温度能显著影响西红花花芽分化的起始和持续长短。低水平的IAA和ABA有助于顶芽向生殖生长转变，GA3是顶芽休眠解除、花芽分化的促进物。同时，较低的ABA/GA3、IAA/GA3、ABA/IAA有利于西红花顶芽从营养生长向生殖生长的转变。 |
| 关键词: 西红花 花芽分化 温度调控 内源激素 |
| DOI： |
| 分类号: |
| 基金项目:上海市市级农口系统青年人才成长计划项目［沪农青(2018)第1-11号］ |
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| Process of floral bud differentiation and dynamic changes of endogenous hormones under different temperatures in saffron (Crocus sativus L.) |
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WANG Zhen,LI Xin,LI Qingzhu,et al
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| Abstract: |
| 【Objective】This study investigated the correlation between temperature and floral bud differentiation as well as dynamic changes of endogenous hormones in the shoot apex with changing temperature to provide basis for standardization of environmental conditions during flowering period in saffron.【Method】Saffron corms were selected to observe floral bud differentiation process of shoot apex and determine ratio of floral bud differentiation under natural temperature and constant temperatures (15,20,25 and 30 ℃).The changes of endogenous hormones including IAA,IBA and GA3 during floral bud differentiation stage were also determined.【Result】Under natural temperature,floral bud differentiation lasted from late July to early September and the whole differentiation process lasted 45-50 days with the type of centripetal development.At constant temperature of 25 ℃,the time of floral bud differentiation lasted from mid July to mid August with a total of about 30-40 days.There was no floral bud differentiation at 15 and 30 ℃,and the ratios of floral bud differentiation were 55% and 96% at 20 and 25 ℃,respectively.The contents of ABA and IAA decreased continuously from dormant stage to early stage of floral bud differentiation,and then increased slightly.The contents of ABA and IAA in flower bud were lower than those in leaf bud.GA3 content increased continuously from dormant stage to stamen differentiation stage,then decreased slightly,and its content in flower bud was higher than in leaf bud.ABA/GA3 and IAA/GA3 remained at low levels during floral bud differentiation stage,and the ratios of ABA/GA3 and IAA/GA3 in flower bud were lower than those in the leaf bud with downward trend.ABA/IAA in leaf bud increased before the differentiation of terminal bud and then decreased,while ABA/IAA in flower bud decreased at initial stage of floral bud differentiation and slightly increased during differentiation stage.【Conclusion】Temperature could significantly affect floral bud initiation and duration of floral bud differentiation in saffron.Low levels of IAA and ABA were beneficial to transition to reproductive growth of shoot apex,and GA3 promoted dormancy breaking and floral bud differentiation.Low levels of ABA/GA3,IAA/GA3 and ABA/IAA were favorable for transition from vegetative growth to reproductive growth of terminal bud in saffron. |
| Key words: saffron (Crocus sativus L.) floral bud differentiation temperature regulation endogenous hormones |
