ibclogo XVI International Botanical Congess

Abstract Number: 6154
Poster No. = 2546


EFFECTS OF PH AND TEMPERATURE ON GROWTH, PHYSIOLOGY AND MORPHOLOGY OF FIVE STRAINS OF ASPERGILLUS FLAVUS


M. Klich and R. Garber, USDA/ARS.SRRC, 1100 Robert E. Lee Blvd. New Orleans, LA 70124-4305, and Xavier Univ., New Orleans, LA


Agar media with pH adjusted to 3, 5, or 7 was inoculated with A. flavus and incubated for 7 days 25, 30, 35, or 40 C. At pH7 colony diameters were consistent at all temperatures, but at other pH levels diameter was influenced by temperature. Percentage of biseriate aspergilla was consistent over all 4 temperatures at pH7, but at pH3 the maximum percentage of biseriate aspergilla was at 25C. At 25C-pH7 only one strain produced sclerotia at pH5 and others at pH7. Afltoxin B1 production was consistently highest at pH5. Temperature yielding the highest afatoxin levels varied with strain. We conclude that there are strain/pH/temperature interactions within this species.

HTML-Version made 7. July 1999 by Kurt Stüber