水淹胁迫下桃金娘叶片生理及荧光特性研究

Effects of Waterlogging Stress on Chlorophyll Fluorescence and Characteristics of Physiological Resistance of Rhodomyrtus tomentosa Seedlings

为了探究桃金娘的耐涝性,为桃金娘的培育及园林绿化管护提供科学指导,采用双套盆法对其进行不同程度的水淹胁迫处理(重度水淹、轻度水淹、正常条件),研究水淹胁迫对桃金娘幼苗叶绿素荧光特性及抗性生理特征的影响。结果表明,随着水淹胁迫程度的加深,桃金娘幼苗出现了不同程度的叶片发黄、卷曲和变黑及掉落等现象,随着胁迫时间的延长,过氧化氢酶、总氧化物歧化酶、脯氨酸、可溶性糖、丙二醛及电解质的渗透率上升,过氧化物酶及叶绿素含量下降,以重度水淹胁迫下变化幅度最为显著;不同程度水淹胁迫对桃金娘幼苗叶绿素荧光参数均产生影响,其潜在活性和潜在最大光能转换效率光猝灭系数及有效量子产额随胁迫时间的延长而降低,非光猝灭系数则上升。因此,桃金娘具有一定的耐涝性,可应用于滨水景观植物绿化中,主要作为水源湿生植物及岸陆陆生植物种植。

In order to explore the waterlogging tolerance of Rhodomyrtus tomentosa and provide scientific guidance for the cultivation and landscaping management of it,different degrees of flooding stress(se‑vere flooding,mild flooding and normal conditions)were applied to treat its seedlings with the double pot setting method.The effects of waterlogging stress on the chlorophyll fluorescence characteristics and resis‑tance physiological characteristics of R.tomentosa seedlings were studied.The results showed that with the deepening of waterlogging stress,the growth of R.tomentosa seedlings was inhibited,and the leaves turned yellow,curled,blackened and dropped in varying degrees.With the extension of stress time,cata‑lase,total oxide dismutase,proline,soluble sugar,malondialdehyde and electrolyte leakage increased,while peroxidase and chlorophyll content decreased,especially under severe waterlogging stress.The po‑tential activity and potential maximum light energy conversion efficiency of R.tomentosa seedlings de‑creased with the extension of stress time,the light quenching coefficient and effective quantum yield de‑creased,and the non-light quenching coefficient increased.The comprehensive analysis of various indi‑cators shows that R.tomentosa seedlings have certain waterlogging resistance,and it can be planted as one of the waterside landscape species.