Three native isolates of Trichoderma viride (I1, I2 and I3) were obtained from the rhizosphere regions of rice fallow blackgram of Karaikal district, U.T. of Pondicherry, The native isolates were tested for their efficacy against Macrophomina phaseolina using three different methods viz. seed. soil and seed+soil application under rice fallow condition. Among the three methods of application, integration of seed and soil application of T. viride (13) recorded increased rhizosphere population of T. viride with reduced population of M. phaseolina leading to reduced percentage disease incidence throughout the crop growth under field conditions.