Wheat is grown because it provides grains for human food and straw that can be fed to ruminants. In recent years, wheat varieties that have shorter, thicker stems for supporting a higher grain yield have been a popular choice by farmers. Straw derived from these wheat varieties has a higher lignin content. Several methods to attempt to improve the nutritional value of wheat straw have been tested without much success, due mainly to the reduced palatability of chemically treated straw, the high cost of the treatments or to the increased labour required to perform the treatment. It has already been shown that some Pleurotus species (white rot fungi of the Basidiomycota) can selectively degrade lignin in wheat straw, making the cellulose and hemi-cellulose move available for digestion by ruminants. Selecting a Pleurotus variety which could be induced to produce edible fruit bodies could result in a profitable enterprise and thus offset the increased costs of a biological treatment. The ability of five strains of Pleurotus to increase the digestibility of wheat straw has been investigated in this study.