GERMINATION AND VIABILITY OF CAPILLICONIDIA OF NEOZYGITES FLORIDANA (ZYGOMYCETES, ENTOMOPHTHORALES) UNDER CONSTANT-TEMPERATURE, HUMIDITY, AND LIGHT CONDITIONS

The germination of capilliconidia of Neozygites floridana on the cassa va green mite, Mononychellus tanajoa, and the viability of these conid ia collected on glass coverslips were studied at different temperature s, humidities (expressed as saturation deficit (SD), measured in mg Hg ), and light conditions. Germination began within 2 hr of their attach ment to the mites, at which time more than 66.0% of the conidia mainta ined at between 18 and 28 degrees C, at SDs 0 and 0.2, and in the dark produced germ tubes. Percent germination pooled across all factors si gnificantly increased from 15.7% after 2 hr to 28.2% after 6 hr and 45 .0% after 14 hr. Germination at the extreme temperatures tested, 24.5% at 13 degrees C and 14.8% at 33 degrees C, was significantly lower th an 40.0, 47.2, and 36.5% recorded at 18, 23, and 28 degrees C, respect ively, Percent germination increased with increasing humidity from 2.8 % at SD 1.2 to 60.9% at SD O. Although germination was observed when b oth light and dark conditions were tested, the 44.9% germination recor ded under continuous darkness after 6 hr was significantly higher than 20.3% under continuous light, Rate of germination of capilliconidia d eclined with increasing storage time from 93.0% before storage to a po oled mean of 81.0% after 1 day and 3.5% after 10 days. Higher germinat ion rates were maintained at lower temperatures, Whereas germination a fter 7 days did not exceed 8.0% at 28 and 33 degrees C, it was 85.9 at SD 10 in the dark at 18 degrees C. Germination at SD 10 was significa ntly higher (43.3%) than at SDs 6, 2, and 0 (between 31.34 and 34.95%) . Continuous light reduced viability as an average of 47.1% of the con idia maintained in the dark germinated, compared to 23.5% of those in the light. (C) 1996 Academic Press, Inc.