芍药不同品种发育过程中花茎细胞壁成分变化

Content changes of cell wall composition during stem development in different varieties of Paeonia lactiflora

花茎挺直是评判芍药切花品质的重要标准之一,但目前影响芍药花茎直立性的因素尚不完全清楚。为明确直立性不同的芍药品种发育过程中花茎细胞壁成分的变化差异,利用花枝夹角指标将6个品种划分为3个直立等级,将现蕾期到花朵盛开的过程划分成S1~S5共5个阶段,观测不同直立等级品种花茎弯曲发生的关键时期及其5个发育阶段细胞壁组分的动态变化。结果表明,切花品种东方少女和杨妃出浴直立性最好,迟粉等3个品种花茎自S2时期起随发育逐渐变弯,晴雯自S4时期起迅速下垂。比较一致的规律是,3个直立等级的品种木质素含量随发育进程均呈升高趋势,水溶性果胶含量自S2时期起呈下降趋势。相关性分析表明,在发育前期花茎直立性和木质素含量极显著正相关;发育中期花茎直立性和木质素含量极显著正相关,和原果胶含量显著负相关;发育后期花茎直立性和半纤维素含量、木质素含量极显著正相关,和水溶性果胶含量显著负相关。研究为切花芍药品种的选育和栽培调控提供了理论依据。

Straight stem is one of the vital standards to judge cut peony.However,the factors affecting stem verticality of Paeonia lactiflora are not clear at present.To clarify the changes of cell wall components in stem characteristics of varieties with different straightness,six varieties were studied,and three levels of straightness were divided based on the angle between flower and plumb line.The process from budding to flower blooming was divided into S1 to S5 stages.Then,the key stage of stem bending in varieties with different straightness and dynamic changes of cell wall components in five stages were studied.The results showed that two cut peonies,Dongfang Shaonv and Yangfei Chuyu had relatively most straight stems.Chifen and other two cultivars bent along with stem development from S2 stage,and Qingwen bent rapidly from S4 stage.Similar trends were found in various cultivars that lignin content increased along with development and water-soluble pectin decreased from S2 stage.Correlation analysis showed that there was a significant positive correlation between stem straightness and lignin content at early development stage.The stem straightness was positively correlated with lignin content and negatively correlated with propectin content in the middle stage of development.The stem straightness was positively correlated with hemicellulose content and lignin content,and negatively correlated with water-soluble pectin content.The result would provide a theoretical basis for breeding and cultivation regulation of cut herbaceous peonies.