An in-block, light microscope viewing procedure for botanical materials in plastic embedments; with emphasis on location and selection of host cell–microbe encounter sites

A generalized procedure for direct, in-block, light microscopic viewing of plastic embedded botanical specimens has been developed that allows users to: (i) quickly and economically survey large numbers of specimens in embedment blocks, (ii) remove unwanted tissue and cell types from viewing areas with little risk of artifact development, (iii) map and photograph locations of desired sectioning sites before block trimming, (iv) view desired sectioning sites during the trimming process, and (v) perform either thick sectioning or ultramicrotomy on specimen blocks manipulated during the procedure.