Plant stomata are an essential route for bacterial pathogens to entry inside host tissue and cause diseases. As an important defense mechanism, plant stomata can actively restrict bacterial invasion by dynamically regulating the opening, closing, and reopening of stomatal guard cells. Therefore, accurately measuring the stomatal aperture size during the bacterial pathogenesis is an important approach to study the stomata related immunity. Several methods have been developed for stomatal aperture measurement. Here, we described a detailed protocol of using clear nail polish to make Arabidopsis epidermal impressions for investigate the change of stomatal aperture size in plant immune response. The application of this approach can instantly fix the status of stomatal guard cells, and provides clear, stable, and almost permanent slides of epidermal impressions for measurement of stomatal aperture size.
Keywords: Arabidopsis thaliana; Epidermal impressions; Nail polish; Stomatal guard cell.