铁核桃叶片矿质元素和内源激素含量与雌花芽分化的关系

摘要

以铁核桃(Juglans sigillata Dode)叶片和花芽为材料,采用石蜡切片法确定铁核桃雌花芽生理分化和形态分化期,并采用分光光度法、凯氏定氮法、钼锑抗比色法以及ASS法测定花芽分化期叶片中叶绿素和主要矿物质含量,运用液质联用法(HPLC-MS)对花芽分化期雌花芽、雄花芽和叶片中内源激素含量进行分析,探讨铁核桃叶绿素、矿物质和内源激素含量与雌花芽分化的关系.结果表明:(1)铁核桃叶片中叶绿素a和叶绿素b的含量在雌花芽生理分化前增加,在形态分化期呈现高峰值.(2)从生理分化到形态分化转换期,铁核桃叶片中Ca、Mg含量降低,K含量升高;在花芽分化过程中,叶片中P含量呈持续下降趋势,Fe含量呈先下降后上升趋势,Zn含量呈‘M’型变化.(3)铁核桃叶片、雌花芽和雄花芽中GA4含量在生理分化期急剧下降,而在形态分化期呈现高峰值;雌花芽、雄花芽中ABA和ZR含量在花芽分化过程中均呈‘M’型双峰曲线,而叶片中ZR浓度持续呈现低含量水平,并在雌花芽分化的生理分化期有峰值;形态分化期花芽中IAA浓度较低.4月底～5月中旬是贵州铁核桃雌花芽由生理分化向形态分化转化的关键期;叶片中高含量的叶绿素和雌花芽中低浓度的IAA、GA4利于雌花芽初期发育;雌花芽分化过程中消耗大量P,叶片中高含量的K与雌花芽分化关键期关系密切,而Ca、Mg、Zn与雌花芽形态分化关系密切;雌花芽中高浓度的ABA、ZR对生理和形态分化均有显著作用,高含量的GA4参与花原基的形态建成.%Taking leaves and flower buds of Juglans sigillata as materials,we observed female bud physiological differentiation stage by paraffin method and determined the contents of chlorophyll and essential minerals nutritions in leaves by method of spectrophotometry,kjeldahl,molybdenum antimony colorimetric and ASS.We also analyzed hormones content in leaves,female bud and male bud by HPLC-MS to research the relationship between chlorophyll,mineral nutritions and hormone contents and flower bud differentiation of J.sigillata.The results showed that:(1) The contents of chlorophyll a and chlorophyll b increased before female flower bud physiological differentiation,and present peak at morphological differentiation stage.(2) From physiological differentiation to the morphological differentiation,Ca and Mg contents reduced,K content increased.In the process of flower bud differentiation,P content showed a trend of declining,Fe content increased then fell,Zn content showed ‘M'type.(3) GA4 content in leaves and female flower buds fell sharply at physiological differentiation stage and present peak at morphological differentiation stage.ABA and ZR contents showed bimodal curve ‘M'type in the process of flower bud differentiation.ZR content in the leaves showed a trend of low content continuously,and has a peak at physiological differentiation stage of female flower bud.The content of IAA was low during early morphological differentiation of flower buds.So,it is the critical period of female flower bud that transformed from physiological differentiation to morphological differentiation between the end of April and the middle of May.High content of chlorophyll in leaves and low contents of IAA,GA4 in female flowers bud were beneficial to female buds early develop.A large amount of P was consumed during flower bud differentiation.High content of K is close to the critical period of female flower buds differentiation and Ca,Mg,Zn contents closely associated with female flower buds morphological differentiation.At the same time,the high contents of ABA,ZR in female flower buds have significant effect to both physiological and morphological differentiation,and high content of GA4 involved in formation of flower primordium.