Regional differences in production of aflatoxin B1 and cyclopiazonic acid by soil isolates of Aspergillus flavus along a transect within the United States.
HORN, B.W. and DORNER, J.W.
Applied and Environmental Microbiology 65 : 1444-1449.
1999
บทคัดย่อ
Soil isolates of Aspergillus flavus from a transect extending from eastern New Mexico through Georgia to eastern Virginia were examined for the production of AFB1 and CPA in a liquid medium. Peanut fields from major peanut-growing regions were sampled, and fields with other crops were sampled in regions where peanuts are not commonly grown. The A. flavus isolates were identified as members of either the L strain which produces sclerotia that are >400mm in diameter, or the S strain which produces numerous small sclerotia that are >400 mM in diameter. The S strain isolates generally produced high levels of AFB1, whereas the L strain isolates were more variable in aflatoxin production; variation in CPA production also was greater in the L strain than in the S strain. Significant differences in production of AFB1and CPA by the L strain isolates were detected among regions. In the western half of Texas and the peanut-growing region of Georgia and Alabama, 62-94% of the isolates produced AFB1at>10 mg/L. The percentages of isolates producing >10 mg/L ranged from 0 to 52% in the remaining regions of the transect; other isolates were often nonaflatoxigenic.