Ph-Related Color Changes in Certain Species of Lazulinospora, Pseudotomentella, and Tomentella

Abstract

SUMMARY The hymenia in basidiocarps of Pseudotomentella atrocyanea (Wakef.) Burds. et M. J. Larsen, Lazulinospora wakefieldii Burds. et M. J. Larsen, L. cyanea (Wakef.) Burds. et M. J. Larsen, Tomentella botryoides (Schw.) Bourd. et Galz., T. griseoviolacea Litsch., and T. ferruginea (Pers. per Pers.: Fr.) Pat., are conspicuous because of a change in wall pigment or diffusate to blue or green when mounted in dilute aqueous KOH. The color change, in buffer solutions ranging from pH 2.6 to 12.6, was related to pH rather than being specific for KOH. The color was most intense at pH 10.0 and 10.7, virtually absent at pH 8.0, and absent at pH 6.8 and below. The color change was reversible. Two specimens of Pseudotomentella atrocyanea (Wakef.) Burds. et M. J. Larsen were recently discovered in Arizona and Lazulinospora wakefieldii Burds. et M. J. Larsen was collected once in central Florida. These fungi and L. cyanea (Wakef.) Burds. et M. J. Larsen (1974) are unusual because of their blue to blue-green basidiocarps and the basidia and basidiospores stain blue in dilute aqueous KOH solution. Basidia and basidiospores of these fungi are microscopically hyaline in distilled H 2O. We postulated that the color reaction in 2% KOH resulted from a high p H, as has been shown for other fungi (Curtin et al., 1940; Sartory and Bainier, 1911; Singer, 1962, p. 94), rather than a specific reaction with KOH. Our tests were designed to determine whether pigments localized in the basidia and spores of P. atrocyanea, L. wakefieldii, and L. cyanea behave as pH indicators. Some tomentelloid fungi are noted for having hyphae or hyphal exudates which turn blue in KOH (Larsen, 1968; 1973) and several have been included.