Further test showed that Nigrospora sp., SH1 and SH2 reduce population growth of A. gossypii, with SH2 provide highest suppression (Figure 1). This was indicated by delaying peak of population growth curve and reducing population density by these fungi treatments. Untreated or control had peak of population growth at 18 days. Population growth curve reached a peak at 18, 20 and 20 days for Nigrospora sp. SH1 and SH2 respectively. Nigrospora sp. SH1 and SH2 suppressed population density at average rate of 29.05%, 40.36% and 54.37% respectively.. Population growth curve reach a peak at 16 and 18 days and suppressing rate of 0.00%and 19.23% for Aspergillus flavus and Coniothyrium sp. respectively. It can be said that Aspergillus and Coniothyrium sp.has minor effect on population growth of A. gossypii, consequently those fungi were not further used in life cycle and fecundity test.