油茶花芽分化形态结构及内源激素变化

以普通油茶(Camellia oleifera) 4个无性系为材料，结合油茶成花的动态观察和花芽分化过程的石蜡切片形态观察，采用酶联免疫吸附分析法测定花芽中玉米素核苷(ZR)、脱落酸(ABA)、生长素(IAA)、赤霉素(GA) 4种内源激素含量，探讨油茶花芽分化与内源激素的关系。油茶花芽分化过程可分为6个时期：前分化期(10 d)、萼片形成期(20 d)、花瓣形成期(30 d)、雌雄蕊形成期(20 d)、子房与花药形成期(10 d)和雌雄蕊成熟期(20 d)，历时3～4个月。油茶不同无性系的花芽分化时间略有不同。油茶花芽中ZR含量相对较低(5.102～16.412 ng·g–1 FW)，ABA含量相对较高(76.815～137.648 ng·g–1 FW)。其中，粤华5号和湘林8号的ZR、ABA含量变化趋势一致，岑软3号和岑软2号含量变化趋势一致。油茶花芽中IAA含量相对较高，为49.072～135.622 ng·g–1 FW，随着花芽分化进程，IAA含量均呈先升后降再升的变化趋势。GA含量相对较低，为5.616～13.720 ng·g–1 FW，随时间变化，呈现出不断降低的趋势。其中，不同无性系的IAA、GA含量变化趋势一致，而ZR、ABA含量变化趋势有所差异。ZR有利于花器官形成；高浓度IAA促进油茶花芽分化，低浓度IAA有利于开花；花芽中IAA与ABA存在明显的颉颃作用；GA抑制花芽分化。

Flower Bud Differentiation and Endogenous Hormones Changes of Camellia oleifera

In order to explore the relationship between endogenous hormones and flowering process of Camellia oleifera, changes of endogenous hormone contents during flower bud differentiation were studied in four C. oleifera clone. Combined with the dynamic observation of C. oleifera flower formation and the morphological observation of paraffin sections in flower bud, the contents of zeatin nucleoside (ZR), abscisic acid (ABA), auxin (IAA) and gibberellin (GA) in Camellia flower bud were determined by enzyme-linked immunosorbent assay. Camellia flower bud differentiation process passed through the pre-differentiation stage (10 d), sepals formation stage (20 d), petal formation stage (30 d), pistil and stamens formation stage (20 d), ovary and florist formation stage (10 d), and pistil and stamens maturation stage (20 d) during 3—4 months. The time of flower bud differentiation was slightly different in different C. oleifera clones. ZR content in Camellia flower bud was relatively low with 5.102—16.412 ng·g–1 FW, but ABA content was relatively high with 76.815—137.648 ng·g–1 FW. Among them, the ZR, ABA content changes of ‘Yuehua 5’ and ‘Xianglin 8’ were similar, and the content changes of ‘Cenruan 3’ and ‘Cenruan 2’ were similar. The content of IAA was relatively high with 49.072—135.622 ng·g–1 FW, they all showed the changing trend of rising slowly, then decreasing and recovering. The GA content was relatively low with 5.616—13.720 ng·g–1 FW. Among them, the trend of IAA, GA content of different Camellia clones were consistent, but the trend of ZR, ABA content was different. ZR was conducive to the formation of flower organs; high concentration of IAA promoted flower bud differentiation, low concentration of IAA favored flowering; IAA and ABA had antagonistic effects obviously; GA inhibited flower bud differentiation.