The effect of osmotic pressure and salinity of the medium on the growth and sporulation of Aspergillus niger and Paecilomyces lilacinum species.

The effect of osmotic pressure and salinity on the production of conidia and growth of Aspergillus niger and Paecilomyces lilacinum, isolated from the soil, have been studied in this investigation. The maximum production of conidia in both species was observed in the nutrient medium containing 1% NaCl wheras maximum growth was recorded in the nutrient medium containing 3% NaCl. It has been thus observed that the salinity and the osmotic pressure related to it effect the reproductive as well as the vegetative development of both species, and these effects have been observed to be different. The sensitivity of both fungal species to the salt was also investigated. Conidia were not observed in the P. lilacinum species grown in nutrient medium with 5% NaCl whereas conidial development did take place in the case of Aspergillus niger grown in the nutrient medium containing 5% NaCl.