PRODUCTION AND GERMINATION OF PRIMARY CONIDIA OF NEOZYGITES FLORIDANA(ZYGOMYCETES, ENTOMOPHTHORALES) UNDER CONSTANT TEMPERATURES, HUMIDITIES, AND PHOTOPERIODS

The production and germination of primary conidia of Neozygites florid ana as affected by temperature, humidity, and photoperiod was studied in the laboratory. All tested factors significantly affected the two p rocesses studied. Production increased with increasing temperature bet ween 13 and 23 degrees C, with means of 35.5 and 55.4 conidia, respect ively, discharged from each mummified mite cadaver. No conidia were pr oduced at 28 or 33 degrees C. Conidial production dropped significantl y from 96.1/mummy in a moisture-saturated environment [saturation defi cit (SD) 0] to 33.9/ mummy at SD 0.2. Very few conidia were produced a t SD 0.7 (0.6/mummy) and none at SD 1.2, Significantly fewer conidia w ere produced under continuous light (11.2/mummy) than under continuous darkness (40.1/ mummy) or 12L:12D (46.7/mummy) photoperiods. Between 82 and 100% of the conidia produced under 12L:12D photoperiod were rel eased in the dark phase. Germination of primary conidia started within 2 hr and increased with decreasing temperature between 13 and 28 degr ees C. Percentage germination of 20.1% at 13 degrees C and 17.6% at 18 degrees C was significantly higher than 11.2% at 28 degrees C. There was no germination at 33 degrees C. High humidities (>95%) were necess ary to effect germination. Germination at SD 0 (27.2%) and 0.2 (23.4%) was significantly higher than at SD 0.7 (0.4%), where germination beg an after 6 hr and was observed only at 13, 18, and 23 degrees C. No ge rmination was observed at SD 1.2. There was no germination among conid ia maintained under continuous light. (C) 1996 Academic Press, Inc.