DOI: 10.5061/dryad.sk35h
title: Data from: Sexual reproduction in Aspergillus flavus sclerotia: acquisition of novel alleles from soil populations and uniparental mitochondrial inheritance

description: 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.
description: Table 1 Raw
 DataContains the raw data
 for Table 1. "Sexual reproduction in A. flavus sclerotia from single
 strains of one mating type when incubated on sterile soil and on soil
 containing natural fungal populations." Includes number of sclerotia
 examined and percent fertile sclerotia for each replicate soil cup of each
 single strain and statistics for comparing the strains.Table 3 Raw
 DataContains the raw data
 for Table 3. "Reciprocal crosses in A. flavus in which single-strain
 sclerotia were incubated on sterilized soil inoculated with conidia."
 Includes number of sclerotia examined and percent fertile sclerotia for
 each replicate soil cup of each cross and statistics for comparing the
 strains.Table 4 Raw
 DataContains the raw data
 for Table 4. "Sexual reproduction in A. flavus sclerotia obtained
 from crosses and incubated under laboratory conditions." Includes
 number of sclerotia examined and percent fertile sclerotia for each
 replicate of each single strain and statistics for comparing the
 strains.Table 6 Raw
 DataContains the raw data
 for Table 6. "Soil populations of Aspergillus section Flavi species
 (CFU/g) in fields prior to application of A. flavus sclerotia.."
 Includes concentrations (CFU/g) for each species examined from five soil
 samples taken from Field A, Field B, and Field C and statistics for
 comparing the concentrations for each field.Table S1 Raw
 DataContains the raw data
 for S1 Table. "Weather conditions at three fields (2013-2014) where
 single-strain and fertilized sclerotia of A. flavus were applied."
 Includes the daily minimum, maximum, and mean temperature for Field A,
 Field B, and Field C from August 16th, 2013 til August 15th, 2014.
 Contains ANOVA results for comparison between the Fields for minimum,
 maximum, and mean temperatures from each month.NRRL29537_and_NRRL29536_progeny_AF-MIT-1Fasta file containing the aligned sequences that distinguish mitochondrial inheritance in the progeny of NRRL 29537 and NRRL 29536. Corresponds to the primer pair AF-MIT-1 (F: TGAAGCAACTGGATTATTCGCA, R: AAACCACATTCAAAAGCGCT).NRRL29507_and_NRRL21882_progeny_AF-MIT-3Fasta file containing the aligned sequences that distinguish mitochondrial inheritance in the progeny of NRRL 29507 and NRRL 21882. Corresponds to the primer pair AF-MIT-3 (F: AGCAGAGGGTTCTGCGTTT, R: GCAGATCAACCTGCTAATAATATTCC).NRRL29473_and_AF36_progeny_AF-MIT-4Fasta file containing the aligned sequences that distinguish mitochondrial inheritance in the progeny of NRRL 29473 and AF36. Corresponds to the primer pair AF-MIT-4 (F: GCTAAAGTTATAGGAGGTGAAGT, R: GCAACCTTTAGCTTCAATAAACCC).