One of the important issues of interest to companies producing biological fungicides is the abilityto market and commercialize such compounds. According to the conducted research, increasingthe efficiency and stability of such compounds is one of the important influencing factors in theirmarketability and commercialization. In this research, sodium nitrate osmotic stabilizer was usedin order to increase the stability of Talaromyces flavus antagonist fungus in liquid formulationprepared with fermenter. First, sodium nitrate was added to the liquid formulation containingT. flavus based on the amount of supplements added to the culture media (ten milliliters of thesupplement solution at the rate of ۲۰ grams per liter for ۲۵۰ grams of each media). To determinethe stability percentage of ascospores of T. flavus fungus, ۹ ml of sterile distilled water was addedto one gram of each formulation and the ascospores in one ml of the obtained suspension werecounted by slide hemocytometer. Then, a suspension with a concentration of ۱۰ ascospores permilliliter was prepared and one milliliter of the prepared suspension was spread on the surface ofeach of the three Petri dishes containing the selected culture medium. Petri dishes were kept in anincubator at ۳۰ degrees Celsius for three to five days. By observing the yellow cells formed on thesurface of the Petri dishes, the percentage of active ascospores of T. flavus in each replicate wasdetermined by calculating the average percentage of spores grown in three Petri dishes. The resultsof previous research had shown that the stability of at least fifty percent of the T. flavus sporespopulation in the liquid formulation containing T. flavus was up to six months after production.The results of this study showed that with the use of sodium nitrate in the liquid formulation ofT. flavus carrier, the stability time has increased up to one year.
