Fungal growth rate and the formation of ethylene in soil.

The rates of ethylene production per unit mass of Mucor hiemalis are highest at low specific growth rates. Thus this fungus probably produces more ethylene in the soil, where growth rates are low, than would have been predicted by laboratory batch culture, where growth rates are high. The rate of utilization of energyyielding substrate by Mucor hiemalisincreases logarithmically with growth rate. This contrasts with the data obtained for Penicillium digitatum and Aspergillus nidulans; it is discussed in terms of the success of Mucor hiemalis as a primary saprophytic sugar fungus.