棉花非叶器官的叶绿素荧光异质性研究

【目的】棉花叶片和非叶器官的结构和功能具有异质性,本文针对这一问题通过叶绿素荧光成像技术来研究叶片和非叶器官的光合异质性。【方法】本试验以陆地棉品种新陆早45号为材料,测定了叶绿素含量和叶绿素荧光参数等,以此探讨棉花叶片和非叶器官的光合特性和异质性。【结果】试验结果表明,棉花叶片及非叶器官均存在光合功能的异质性。通过比较不同器官的异质性表明,与叶片相比,非叶器官光合功能的变异程度较大;且不同参数的异质性随光照强度而变化。无论叶片还是非叶器官,与光化学过程相关的参数均随光照强度增加异质性变大,而与非光化学过程相关的参数均表现出随光照强度增加异质性变小的特点。【结论】在研究过程中,如使用普通光纤式叶绿素荧光仪来测定样品(叶片等)的光合性能时,需要对样品的不同部位进行多次测定,才能更好地反映所测定组织的光合性能。而如需要较精确的光化学猝灭或者非光化学猝灭相关的参数时,无论叶片还是非叶器官均需要加大测定的重复数来进行分析,以达到更为准确的目的。

Heterogeneity of Chlorophyll Fluorescence Characteristics of Leaves and Non-Foliar Organs of Cotton

Objective]Cotton leaves and non-foliar organs exhibit heterogeneity in structure and function.Methods] In the study,we used chlorophyll fluorescence imaging techniques to investigate the photosynthetic heterogeneity of leaves and non-foliar organs of upland cotton Xinluzao 45.Results] Our analysis confirmed the existence of photosynthetic heterogeneity in cotton leaves and non-foliar organs.Compared with cotton leaves,non-foliar organs were more photosynthetically heterogeneous.In both leaves and non-foliar organs,the degree of heterogeneity of the different measured parameters changed with light intensity:the heterogeneity of parameters photochemical process-related increased with light intensity,while that of non-photochemical process-related parameters decreased.Conclusion] To better reflect organic photosynthetic performance,different parts of sampled plants should be measured.Increasing the number of measured sitesper organis needed to more precisely determine photochemical and non-photochemical quenching parameters.