Regional Differences in Production of Aflatoxin B1 and Cyclopiazonic Acid by Soil Isolates of Aspergillus flavus along a Transect within the United States
AUTOR(ES)
Horn, B. W.
FONTE
American Society for Microbiology
RESUMO
Soil isolates of Aspergillus flavus from a transect extending from eastern New Mexico through Georgia to eastern Virginia were examined for production of aflatoxin B1 and cyclopiazonic acid in a liquid medium. Peanut fields from major peanut-growing regions (western Texas; central Texas; Georgia and Alabama; and Virginia and North Carolina) 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 (n = 774), which produces sclerotia that are >400 μm in diameter, or the S strain (n = 309), which produces numerous small sclerotia that are <400 μm in diameter. The S-strain isolates generally produced high levels of aflatoxin B1, whereas the L-strain isolates were more variable in aflatoxin production; variation in cyclopiazonic acid production also was greater in the L strain than in the S strain. There was a positive correlation between aflatoxin B1 production and cyclopiazonic acid production in both strains, although 12% of the L-strain isolates produced only cyclopiazonic acid. Significant differences in production of aflatoxin B1 and cyclopiazonic acid 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 to 94% of the isolates produced >10 μg of aflatoxin B1 per ml. The percentages of isolates producing >10 μg of aflatoxin B1 per ml ranged from 0 to 52% in the remaining regions of the transect; other isolates were often nonaflatoxigenic. A total of 53 of the 126 L-strain isolates that did not produce aflatoxin B1 or cyclopiazonic acid were placed in 17 vegetative compatibility groups. Several of these groups contained isolates from widely separated regions of the transect.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=91204Documentos Relacionados
- Production of cyclopiazonic acid by Aspergillus flavus Link.
- Production of Aflatoxins B1 and G1 by Aspergillus flavus in a Semisynthetic Medium
- Aflatoxin and cyclopiazonic acid production by a sclerotium-producing Aspergillus tamarii strain.
- Cyclopiazonic acid production by Aspergillus flavus and its effects on broiler chickens.
- Detection of Aflatoxin B1 in Silkworm Larvae Attacked by an Aspergillus flavus Isolate from a Sericultural Farm