@article{molo_white_cornish_gell_baars_singh_carbone_isakeit_wise_woloshuk_et al._2022, title={Asymmetrical lineage introgression and recombination in populations of Aspergillus flavus: Implications for biological control}, volume={17}, ISSN={["1932-6203"]}, url={https://doi.org/10.1371/journal.pone.0276556}, DOI={10.1371/journal.pone.0276556}, abstractNote={Aspergillus flavus is an agriculturally important fungus that causes ear rot of maize and produces aflatoxins, of which B 1 is the most carcinogenic naturally-produced compound. In the US, the management of aflatoxins includes the deployment of biological control agents that comprise two nonaflatoxigenic A . flavus strains, either Afla-Guard (member of lineage IB) or AF36 (lineage IC). We used genotyping-by-sequencing to examine the influence of both biocontrol agents on native populations of A . flavus in cornfields in Texas, North Carolina, Arkansas, and Indiana. This study examined up to 27,529 single-nucleotide polymorphisms (SNPs) in a total of 815 A . flavus isolates, and 353 genome-wide haplotypes sampled before biocontrol application, three months after biocontrol application, and up to three years after initial application. Here, we report that the two distinct A . flavus evolutionary lineages IB and IC differ significantly in their frequency distributions across states. We provide evidence of increased unidirectional gene flow from lineage IB into IC, inferred to be due to the applied Afla-Guard biocontrol strain. Genetic exchange and recombination of biocontrol strains with native strains was detected in as little as three months after biocontrol application and up to one and three years later. There was limited inter-lineage migration in the untreated fields. These findings suggest that biocontrol products that include strains from lineage IB offer the greatest potential for sustained reductions in aflatoxin levels over several years. This knowledge has important implications for developing new biocontrol strategies.}, number={10}, journal={PLOS ONE}, author={Molo, Megan S. and White, James B. and Cornish, Vicki and Gell, Richard M. and Baars, Oliver and Singh, Rakhi and Carbone, Mary Anna and Isakeit, Thomas and Wise, Kiersten A. and Woloshuk, Charles P. and et al.}, editor={Nierman, William C.Editor}, year={2022}, month={Oct} }
 @article{gell_carbone_2019, title={HPLC quantitation of aflatoxin B1 from fungal mycelium culture}, volume={158}, ISSN={0167-7012}, url={http://dx.doi.org/10.1016/j.mimet.2019.01.008}, DOI={10.1016/j.mimet.2019.01.008}, abstractNote={Aflatoxins are mycotoxins that contaminate agricultural products when infected by toxigenic Aspergillus flavus. Methods for quantifying aflatoxin from culture using chromatography are available but are not optimized for population studies. We provide details of a method for preparation and quantitation of aflatoxin B1 from fungal cultures that satisfy those needs.}, journal={Journal of Microbiological Methods}, publisher={Elsevier BV}, author={Gell, Richard M. and Carbone, Ignazio}, year={2019}, month={Mar}, pages={14–17} }
 @article{horn_gell_singh_sorensen_carbone_2016, title={Sexual Reproduction in Aspergillus flavus Sclerotia: Acquisition of Novel Alleles from Soil Populations and Uniparental Mitochondrial Inheritance}, volume={11}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0146169}, abstractNote={Aspergillus flavus colonizes agricultural commodities worldwide and contaminates them with carcinogenic aflatoxins. The high genetic diversity of A. flavus populations is largely due to sexual reproduction characterized by the formation of ascospore-bearing ascocarps embedded within sclerotia. A. flavus is heterothallic and laboratory crosses between strains of the opposite mating type produce progeny showing genetic recombination. Sclerotia formed in crops are dispersed onto the soil surface at harvest and are predominantly produced by single strains of one mating type. Less commonly, sclerotia may be fertilized during co-infection of crops with sexually compatible strains. In this study, laboratory and field experiments were performed to examine sexual reproduction in single-strain and fertilized sclerotia following exposure of sclerotia to natural fungal populations in soil. Female and male roles and mitochondrial inheritance in A. flavus were also examined through reciprocal crosses between sclerotia and conidia. Single-strain sclerotia produced ascospores on soil and progeny showed biparental inheritance that included novel alleles originating from fertilization by native soil strains. Sclerotia fertilized in the laboratory and applied to soil before ascocarp formation also produced ascospores with evidence of recombination in progeny, but only known parental alleles were detected. In reciprocal crosses, sclerotia and conidia from both strains functioned as female and male, respectively, indicating A. flavus is hermaphroditic, although the degree of fertility depended upon the parental sources of sclerotia and conidia. All progeny showed maternal inheritance of mitochondria from the sclerotia. Compared to A. flavus populations in crops, soil populations would provide a higher likelihood of exposure of sclerotia to sexually compatible strains and a more diverse source of genetic material for outcrossing.}, number={1}, journal={PLOS ONE}, author={Horn, Bruce W. and Gell, Richard M. and Singh, Rakhi and Sorensen, Ronald B. and Carbone, Ignazio}, year={2016}, month={Jan} }