Abstract:

Heat-tolerance experiments were conducted among Beauveria bassiana isolates collected from Drosicha corpulenta Kuwana in Yantai City to examine the high temperature influence on the germination rates of conidia. Germination of conidia was assessed after 1, 2, 3, 4, 5 h of incubation at 37, 38, 39 or 40℃. The germination rates of conidia, from 65% to 98%, were not markedly influenced after isolates being exposed to 37℃ for 1, 2, 3, 4 or 5 h. While the germination rates of conidia, ranging 4% to 90% were markedly declined with increasing exposure temperature (38, 39, or 40℃) and time (1, 2, 3, 4 or 5 h). CYT5 and CYT10 isolates displayed higher the germination rates of conidia (86%-90%) than other isolates after 1 h of incubation at 40℃. The results showed that CYT5 and CYT10 were the most-tolerant isolates. In general, the germination of conidia was restrained by high temperature.