Application of uranine for vital staining of Erysiphe graminis f. sp. hordei.

Abstract

Vital staining by uranine on conidia or mycelia of Erysiphe graminis f. sp hordei was investigated. When conidia blown onto glass-slides or mycelia developed on primary leaves of barley cultivar, Trebi I, were stained, brilliant green fluorescence was observed in both conidia and mycelia under a fluorescent microscope. Cytoplasm in living cells was the site of uranine-accumulation. No inhibitive effect of uranine on spore germination or mycelial growth was observed. Autoclaved conidia and mycelia with disorganized cytoplasm showed dull yellow fluorescence. Fluorescent intensity of uranine in these cells decreased rapidly by 7-8min NUV-irradiation of B-excitation light from the fluorescent microscope and brilliant green fluorescence changed into dull yellow with disorganization of conidial or mycelial cytoplasm for about 5min irradiation. These results suggested that living conidia or mycelia of E. graminis f. sp. hordei showed brilliant green fluorescence in the organized cells and could be distinguished from dead ones showing dull yellow fluorescence. In conclusion, the present method is proved to be available for investigation on vital behavior of parasitic cells in the tissues of host-parasite interaction in vivo.