Visualisation of calcium oxalate crystal macropatterns in plant leaves using an improved fast preparation method

Abstract

Abstract Leaves of the majority of plants contain calcium oxalate (CaOx) crystals or druses which often occur in spectacular distribution patterns. Numerous studies on CaOx in plant tissues across many different plant groups have been published, since it can be visualised readily under a light microscope (LM). However, there is surprisingly limited knowledge on the actual, precise distribution of CaOx in the leaves of quite ordinary plants such as common native and exotic trees. Traditional sample preparation for the documentation of the distribution of CaOx crystals in a given sample – including overall distribution – requires time‐consuming clearing procedures. Here we present a refined fast preparation method to visualise the overall CaOx complement in a sample: The plant material is ashed and the ash viewed under the polarising microscope. This is a rapid method which overcomes many shortcomings of other methods and permits the visualisation of the entire CaOx content in most leaf samples. Pros and cons in comparison with the conventional clearing technique are discussed. Further aspects for CaOx investigations by micro‐CT and scanning electron microscopy are discussed.

Plant phenotyping relevance

葉中のシュウ酸カルシウム結晶の分布を可視化する試料調製法を開発・改良し、従来法と比較しているため、植物形質取得法が中心である。

Code and data availability

The article describes microscopy methods (Pol-LM, incineration, SEM, micro-CT) and plant material from Bonn Botanical Gardens, but contains no public phenotype dataset, image repository, analysis code, or supplement with an authors' deposit URL. No qualifying paper-specific public assets are present.

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