Biological control of Fusarium salani (Mart) Sacc. and Macrophomina phaseolina (Tassi) Goid causing wilt and charcoal rot diseases of Sesame (Sesamum indicum Linn) was studied in vitro as well as under pot conditions. Culture technique showed that the addition of intact Nostoc sp SAG2306 or its sonicate inhibited the radial mycelial growth of the test pathogens. Application of Nostoc sonicates resulted in the lowest infection percentage (11.11 % and 17.78 % of Fusarium and Macrophomina respectively) whereas in the control it was 95.55%. Under pot conditions, plant height, fresh and dry weight of plants was found to increase significantly as a result of the inhibition of fungal by Nostoc. Similar results were observed in chlorophyll (ch.la&ch.lb) content of the treated plants. Infection enhanced proline accumulation that was lowered upon Nostoc addition; indicating alleviation of infection ascribed stress.