Effect of Zinc Sulfate and Copper Sulfate on Mycelial Growth, Spore Production and Spore Germination of an Entomopathogenic Fungus Beauveria bassiana

Abstract

The effect of heavy metals including zinc sulfate (ZnSO4) and copper sulfate (CuSO4) on the mycelial growth, spore production and spore germination of Beauveria bassiana was investigated in a laboratory experiment. ZnSO4 or CuSO4 concentrations varied from 0.025 to 0.20 M were added to the PDA medium after its sterilization and then were incubated at room temperature (30 ± 2 0C) for 15 days. The results showed that 0.15 and 0.2 M ZnSO4 and all concentrations of CuSO4 could inhibit fungal growth for 100% and spore germination for 98.5-100%. In addition, in those concentration, the fungal spore production was in the range of 1.7-5.5×106 spores mL-1 which was lower than the controlled (8.035 × 108 spores mL-1) significantly (p <0.01). However, 0.025, 0.05 and 0.10 M ZnSO4 could inhibit fungal growth in a range of 39.0 - 84.8% and spore germination around 67.5-80.5%.