浙北地区红美人杂柑成花过程及其生理生化特征

Flower bud formation and physiological biochemistry characteristics of Hongmeiren citrus hybrid in northern Zhejiang,China

研究红美人杂柑不同结果母枝花芽分化规律和生理生化特征,为红美人成花调控和栽培管理技术提供理论依据。以6年生红美人杂柑为材料,采用冷冻切片技术对花芽的形态特征进行观察,分别用液相色谱质谱联用和元素分析仪测定花芽内源激素[脱落酸(ABA)、玉米素核苷(ZR)、赤霉素(GA)、生长素(IAA)]和叶片碳氮含量。红美人花芽分化过程可分为6个时期,分别为未分化期、分化初期、萼片分化期、花瓣分化期、雄蕊分化期和雌蕊分化期。各种类型结果母枝均为前端梢较中、后端梢花芽分化进程快、成花能力强。成花能力强的枝梢,碳氮比(C/N)、ABA/GA、ZR/GA、IAA/GA高,即三次梢的秋梢高于夏梢和春梢,二次梢(春夏梢)的夏梢高于春梢,二次梢(春秋梢)的秋梢高于春梢。花瓣分化期之前,GA含量高,ABA和ZR含量、ABA/GA、ZR/GA均处于较低水平;进入雄蕊分化期和雌蕊分化期后,ABA和ZR含量、ABA/GA、ZR/GA均快速上升。红美人杂柑不同类型结果母枝前端梢成花能力强,中、后端梢成花能力弱,这与花芽分化进程、营养物质积累、内源激素水平的差异有关,其中激素起主要调控作用。浙北地区设施条件下,雄蕊分化期前后(2月5日到2月20日)是花芽分化的关键时期。因此,红美人杂柑在众多的栽培管理过程中,要特别重视不同类型结果母枝的合理配置,以及夏、秋梢摘心及其放梢时间节点的把握,并尝试利用激素调控花芽分化。

In order to reveal the flower bud differentiation rules and physiological biochemistry characteristics of different female branches of Hongmeiren citrus hybrid,and provide theoretical basis for the regulation of flowering and cultivation management.6-year-old Hongmeiren citrus hybrid trees were used as materials.The frozen section technology was used to observe the morphological characteristics.In addition,endogenous hormones[abscisic acid(ABA),trans-zeatin-riboside(ZR),gibberellin(GA)and indole-3-acetic acid(IAA)]were determined by LC-MS and the leaves were dried for total carbon and nitrogen content determination.The morphological differentiation of flower buds was divided into 6 stages,including undifferentiated stage,initial differentiation stage,sepal differentiation stage,petal differentiation stage,stamen differentiation stage and pistil differentiation stage.The general trend was that the flower bud differentiation process of the front end shoots was faster than that of the middle and rear end shoots,and the proportion of flower bud in the pistil differentiation stage was higher.In three shoots,the carbon/nitrogen ratio(C/N),ABA/GA,ZR/GA,IAA/GA of autumn shoot in spring shoot and summer shoot and autumn shoot(SSA-AU)were higher than that of summer shoot in spring shoot and summer shoot and autumn shoot(SSA-SU)and spring shoot in spring shoot and summer shoot and autumn shoot(SSA-SP),while the C/N,ABA/GA,ZR/GA,IAA/GA of summer shoot in spring shoot and summer shoot(SS-SU)were higher than that of spring shoot in spring shoot and summer shoot(SS-SP),and the C/N,ABA/GA,ZR/GA,IAA/GA of autumn shoot in spring shoot and autumn shoot(SA-AU)were higher than that of spring shoot in spring shoot and autumn shoot(SA-SP).Before petal differentiation stage,GA content was high,ABA content,ZR content,ABA/GA and ZR/GA were all at low levels;after entering stamen differentiation stage and pistil differentiation stage,ABA content,ZR content,ABA/GA and ZR/GA all increased rapidly.Flower formation of the front end shoots was better,and the flower formation ability of middle and rear end shoots were weak,which was related to the difference in flower bud differentiation process,nutrient accumulation and endogenous hormone levels,and the hormones played a major regulatory role.The stamen differentiation stage(February 5 to February 20)was the critical period.Therefore,in the process of cultivation and management,special attention should be paid to the rational allocation of different types of female branches,the timing of topping and shoot release in summer and autumn,and trying to use hormones to regulate flower bud differentiation.