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Updated: Jul 11, 2026

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Sexual Development and Ascospore Discharge in Fusarium graminearum
Published on: March 29, 2012
Recurring origins of allopolyploid species in asplenium
Abstract:
A large proportion of plant species has originated through allopolyploidy: interspecific hybridization followed by chromosome doubling. Heterozygosity remains fixed in allopolyploids because of nonsegregation of parental chromosomes. Two allotetraploid species of the fern genus Asplenium show allozyme polymorphisms at loci that are polymorphic in their diploid progenitors, indicating that each has originated more than once and implicating continued gene flow from diploids to tetraploids.
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