Page Banner

United States Department of Agriculture

Agricultural Research Service

Research Project: CONTROL MECHANISMS FOR MYCOTOXIN PREVENTION IN PEANUTS AND THEIR ROTATION CROPS

Location: Peanut Research

Title: Sexual Reproduction in Aflatoxin-Producing Aspergillus nomius

Authors
item Horn, Bruce
item Moore, Geromy -
item Carbone, Ignazio -

Submitted to: Mycological International Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: June 28, 2010
Publication Date: N/A

Interpretive Summary: none required.

Technical Abstract: Aflatoxins are fungal secondary metabolites that exhibit carcinogenic, hepatotoxic and immunosuppressive properties. Aspergillus nomius is a potent producer of aflatoxins and was formerly considered to be strictly asexual in reproduction. In this research, mating-type genes MAT1-1 and MAT1-2 were identified and crosses were made between sexually compatible strains. An incubation period of 5 to 10 months resulted in the formation of multiple nonostiolate ascocarps within stromata, which places the teleomorph in the genus Petromyces. Ascocarp and ascospore morphology in Petromyces nomius were similar to that of P. flavus and P. parasiticus and differences between teleomorphs were insufficient for species separation. Formation of mature ascocarps was infrequent, with only 24% of the 83 crosses producing viable ascospores. The majority of P. nomius strains were either MAT1-1 or MAT1-2, but several strains contained both genes. MAT1-1/MAT1-2 strains were self sterile and capable of mating with both MAT1-1 and MAT1-2 strains; hence, P. nomius appears to be functionally heterothallic.

Last Modified: 7/30/2014
Footer Content Back to Top of Page