Peyronellaea glomerata — A fungus growing within the fibres of the unshorn fleece

Abstract

Fleece wool affected by the fungus Peyronellaea glornerata had dark-coloured tips similar to wool contaminated by grease and dust, but the colour could not be removed with water and detergents or extracted with solvents. Hyphae were found within wool fibres and, where fruiting structures formed, the overlying cortical and cuticular cells were ruptured.

The fungus utilized nitrate, nitrite, ammonium, amide nitrogen, and wool; it grew well and sporulated with glucose, sucrose, lactose, and starch as sole carbon sources. Growth was sparse when cellulose and Wool were the sole carbon sources, but satisfactory with peptone. The fungus grew best on tryptone–glucose extract agar (Difco) at 26°C.

In culture on a mineral medium with wool sterilized by ethylene oxide, only wool fibres from the distal ends of the staple were attacked by the fungus, brush ends being formed, and cortical cells were released into the medium; whereas with wool sterilized by autoclaving, the fibres were attacked throughout their entire length.