title: Molecular characterization of atoxigenic Aspergillus flavus isolates collected in China.
abstract: Aspergillus flavus strains were isolated from peanut fields of Liaoning, Shandong, Hubei and Guangdong Provinces in China, and identified through phenotypic and molecular approaches. Of the 323 A. flavus strains isolated, 76 strains did not produce aflatoxins detectable by UPLC. The incidence of atoxigenic A. flavus strains decreased with increase in temperature and increased with increase in latitude in different geographical locations. Amplification of all the aflatoxin genes in the aflatoxin gene cluster in the atoxigenic isolates showed that there were 25 deletion patterns (A-Y), with 22 deletion patterns identified for the first time. Most of the atoxigenic A. flavus isolates with gene deletions (97%) had deletions in at least one of the four genes (aflT, nor-1, aflR, and hypB), indicating that these four genes could be targeted for rapid identification of atoxigenic strains. The atoxigenic isolates with gene deletions, especially the isolates with large deletions, are potential candidates for aflatoxin control.
authors.affiliation: Institute of Agro-products Processing Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing, 100193, P. R. China.
authors.forename: Dandan
authors.initials: D
authors.lastname: Wei
authors.forename: Lu
authors.initials: L
authors.lastname: Zhou
authors.forename: Jonathan Nimal
authors.initials: JN
authors.lastname: Selvaraj
authors.forename: Chushu
authors.initials: C
authors.lastname: Zhang
authors.forename: Fuguo
authors.initials: F
authors.lastname: Xing
authors.forename: Yueju
authors.initials: Y
authors.lastname: Zhao
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000348:Aflatoxins / Q000235:genetics / Q000378:metabolism*; D010367:Arachis / Q000254:growth & development; D001231:Aspergillus flavus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D002681:China; D004271:DNA, Fungal / Q000235:genetics; D017353:Gene Deletion; D005800:Genes, Fungal; D005838:Genotype; D005843:Geography; D016133:Polymerase Chain Reaction; D013696:Temperature
chemical_list: D000348:Aflatoxins; D004271:DNA, Fungal