2个果梅品种雌蕊分化进程及相关生化指标分析

Analyses on pistil differentiation process and related biochemical indexes of two cultivars of Prunus mume

为了解果梅(Prunus mume Sieb.et Zucc.)雌蕊分化进程及其败育机制,采用石蜡切片法观察了不同时期果梅品种‘龙眼’(‘Longyan’)和‘大嵌蒂’(‘Daqiandi’)花芽纵切面的解剖结构,并对2个品种不同时期花器官发育状况、花芽百分率、花芽纵径和横径以及花芽中的可溶性糖、可溶性蛋白质和淀粉含量进行了测定分析。结果显示:雌蕊分化期、雌蕊分化末期及盛花期,品种‘龙眼’的不完全花比例均显著小于品种‘大嵌蒂’,其中,盛花期‘龙眼’不完全花比例仅为5.0%,而‘大嵌蒂’不完全花比例高达76.3%。品种‘龙眼’雌蕊分化过程经历未分化期、分化初期、分化期及分化末期4个阶段,且最终有95.0%的花芽在分化末期能顺利形成完全花;品种‘大嵌蒂’雌蕊分化过程则包含未分化期、分化初期、分化期、解体期、解体后修复期和分化末期6个阶段,且仅有23.7%的花芽能形成完全花。雌蕊分化的不同阶段2个品种花芽纵径和横径的变化与其分化进程基本一致。品种‘龙眼’完全花的可溶性糖和可溶性蛋白质含量均高于品种‘大嵌蒂’的完全花和不完全花、淀粉含量则低于后两者;品种‘大嵌蒂’不完全花的可溶性糖和可溶性蛋白质含量最低、淀粉含量则最高,与2个品种的完全花有显著差异。综合分析结果表明:品种‘大嵌蒂’的花芽在12月中上旬停止伸长生长、雌蕊分化停滞直至逐渐解体,这一时期即为品种‘大嵌蒂’雌蕊败育的关键时期;导致果梅雌蕊选择性败育的原因可能与花芽中大分子营养物质的分解代谢有关。

In order to understand the pistil differentiation process of Prunus mume Sieb.et Zucc.and its abortion mechanism,the anatomical structure of longitudinal section of flower bud of two cultivars ＇Longyan＇ and ＇Daqiandi＇ of P.mume at different stages was observed by paraffin method.The development state of flower organ,percentage of flower bud,longitudinal and horizontal diameters of flower bud at different stages,and contents of soluble sugar,soluble protein and starch in flower bud of two cultivars were determined and analyzed.The results show that imperfect flower rate of cultivar ＇Longyan＇ is significantly lower than that of cultivar ＇Daqiandi＇ at pistil differentiation,late differentiation and full flowering stages,in which,that of cultivar ＇Longyan＇ is only 5.0% while that of cultivar ＇Daqiandi＇ is up to 76.3% at full flowering stage.The pistil differentiation process of cultivar ＇Longyan＇ goes through four stages including pre-differentiation,early differentiation,differentiation and late differentiation stages,and finally,95.0% flower buds can smoothly form perfect flower at late differentiation stage.That of cultivar ＇Daqiandi＇ goes through six stages including pre-differentiation,early differentiation,differentiation,disintegration,repair after disintegration and late differentiation stages,and only 23.7% flower buds can form perfect flower.At different stages of pistil differentiation,the change of longitudinal and horizontal diameters of flower buds of two cultivars is basically consistent with pistil differentiation process.Contents of soluble sugar and soluble protein in perfect flower of cultivar ＇Longyan＇ are higher than those in perfect and imperfect flowers of cultivar ＇Daqiandi＇,and its starch content is lower than that of the latter two flowers.While contents of soluble sugar and soluble protein in imperfect flowers of cultivar ＇Daqiandi＇ all are the lowest and its starch content is the highest with significant difference to those in perfect flower of two cultivars.Comprehensive analysis results indicate that during the first and second ten days of December,flower bud of cultivar ＇Daqiandi＇ does not continue to elongate,its pistil differentiation stagnates until gradual disintegration,which is the key stage of pistil abortion of cultivar ＇Daqiandi＇.The factors leading to selective abortion of P.mume pistil may relate to catabolism of macromolecule nutrients in flower bud.