Microfluorometry of pectic materials in the dehiscence zone of almond (Prunus dulcis [Mill.] DA Webb) fruits.

We examined the middle lamella and the primary and secondary walls in almond pericarp dehiscence zone cells using a fluorescent cytochemical method which permitted specific, quantitative detection of pectic cell wall materials. Glycol methacrylate-embedded sections were stained with coriphosphine and pectin-specific fluorescent emissions at 630 nm were quantified using green excitation (546 nm). Examination of sectioned material extracted with purified pecto-lytic enzyme preparations was used to demonstrate the relative specificity of the staining reaction for pectic substances.