Published online by Cambridge University Press: 05 December 2011
The microbial populations on cereal straw at harvest are characteristic of the phylloplane. Incorporation of straw into soil represents an enrichment disturbance and results in a rapid stimulation of soil microbial activity. The dominant fungal colonists of the straw in soil were found to vary with soil water potential over a twenty-eight week period of incorporation. The dominant fungal genera were Penicillium and Mucor, followed by Gliocladium, Fusarium and Trichoderma. Basidiomycetes were only isolated from straw in a wet (−0.1 MPa) soil. Prior inoculation of straw with Gliocladium roseum (Link) Banier resulted in changes in the dominance of these fungi, particularly in a dry soil. In vitro data on spore germination, germ tube extension and growth of these soil fungi on agar media were not correlated with those on unsterile straw leaf sheaths or sterile straw segments.