  We develop an unstructured mathematical model describing the growth kinetics
of the Trichoderma fungus and the production of enzymes (cellulase) by
degradation of a substrate (cellulose) in the rhizosphere. We integrate into
this model the hydrolysis step of the organic matter and analyze the asymptotic
behaviour of the obtained system. We show that our system evolves towards a
global attractor consisting of infinite non-hyperbolic equilibria.
