APPLICATIONS OF KOH-ANILINE BLUE FLUORESCENCE IN THE STUDY OF PLANT-FUNGAL INTERACTIONS

A KOH-aniline blue technique for fluorescent staining of fungi in asso ciation with plant tissues was developed. The technique provided rapid , simple, and effective documentation of plant-fungal interactions wit h specimens representing the Deuteromycotina, Ascomycotina, Basidiomyc otina, and Mastigomycotina. Applications of the technique were investi gated, including documentation of host-penetration events, characteris tics of host colonization, fungal reproduction, acid detection of inoc ulum. In the standard KOH-aniline blue procedure, fresh specimens were autoclaved for 15 min at 121 degrees C in 50 ml of 1 M KOH, rinsed in deionized water, mounted in the stain solution, and examined with ult raviolet fluorescence. The stain solution was prepared as 0.05% anilin e blue dye (CI #42755 or CI #42780) in 0.067 M K2HPO4 at pH 9.0. Modif ications of the standard procedure also were tested, including use of variously preserved specimens, alteration of the KOH treatment, and mo derate variation of the stain solution. The technique produced a high degree of resolution and contrast between hyphae and host-plant tissue s. The resulting documentation supported previous observations and, in some cases, provided new information about the nature of specific hos t-pathogen interactions.