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Initial resting spore germination for two isolates (RF 150 and RF 250) of Entomophaga calopteni (Bessey) Humber [=Entomophaga grylli (Fresenius) Batko, pathotype 2], a fungal pathogen of grasshoppers (Acrididae), was recorded for five different buffer systems: orthophosphate (OPHO), citrate-phosphate (CPHO), tris (hydroxymethyl) aminomethane (THMM), glycine-NaOH (GLYC), and tris-maleate (TMAL). For each buffer system, eight pH levels were tested ranging from 4 to 11. GLYC at pH 7–9 supported the highest germination percentages compared with the other combinations tested. In general, highest germination levels for all buffer systems occurred in the pH range of 6–8, although they were skewed toward the basic side of the pH scale in OPHO, THMM, and GLYC for isolate RF 150. THMM supported germination better than any other buffer system under highly alkaline conditions. Soil pH may be an important factor in disease transmission under natural conditions. The combined effects of temperature, photoperiod, pH, and buffer medium should be considered when reporting and comparing spore germination levels.