Reproductive systems: Sex and the single lichen

  title={Reproductive systems: Sex and the single lichen},
  author={Gareth J. Murtagh and Paul S. Dyer and Peter D. Crittenden},
Most lichenized fungi produce abundant sexual structures, and in many species sexual spores seem to provide the only means of dispersal. For example, 90% of lichens found in Great Britain and Ireland produce ascomata (fruit bodies) containing sexually derived ascospores, whereas only 29% form symbiotic vegetative propagules. Sex in lichenized fungi has been assumed to equate with outcrossing, but failure to induce sexuality in vitro has prevented experimental investigation of their breeding… 
Twenty-seven modes of reproduction in the obligate lichen symbiosis
A new conceptual framework describing reproductive modes in lichens is presented that includes sexual and asexual processes as well as accommodating the possibility of parasexual reproduction, allowing for a greater plurality of reproductive processes than previously acknowledged in lichenized fungi.
Induction of the Sexual Cycle in Filamentous Ascomycetes
Methods to induce a sexual cycle in various filamentous fungi, including the use of mating-type gene diagnostics to identify compatible mating types in heterothallic ascomycete species, are described and ways in which the sexual cycle can be exploited are covered.
Sex and the Imperfect Fungi.
It is suggested that, although rare, imperfect fungi may genuinely be present in nature and that certain human activities, combined with the genetic flexibility that is a hallmark of the fungal kingdom, might favor the evolution of asexuality under certain conditions.
Multiple Mating Events and Spermatia-Mediated Gene Flow in the Lichen-Forming Fungus Lobaria pulmonaria
Results show that spermatia are an important source of gene flow with dispersal distances in the same order of magnitude as vegetative and sexual diaspores and confirms a heterothallic mating system in L. pulmonaria.
Molecular evidence for limited dispersal of vegetative propagules in the epiphytic lichen Lobaria pulmonaria.
  • J. Walser
  • Environmental Science, Biology
    American journal of botany
  • 2004
The genetic structure of three Lobaria pulmonaria (Lobariaceae) populations from Switzerland was investigated based on the observed variation at six microsatellite loci and the restricted occurrences of common genotypes as well as the clustered distributions are evidence for a limited dispersal of vegetative propagules in L. pul monaria.
Recombination and clonal propagation in different populations of the lichen Lobaria pulmonaria
High genetic diversity within all 12 investigated populations and evidence of recombination, from various tests, indicated that L. pulmonaria is a predominantly outcrossing species, but the presence of recurring multilocus genotypes influenced the spatial genetic structure only within low-density populations.
A review of existing whole genome data suggests lichen mycelia may be haploid or diploid
New whole genome assemblies from seven unrelated lichens are presented and metagenome samples indicate that two are likely haploid or highly homozygous diploid as a result of clonal mating whereas the remaining two yielded highly skewed allelic ratios that warrant further study.
Population genetics of lichen-forming fungi – a review
The literature available on the genetic structure of lichen fungi is reviewed to show general trends, and some fascinating examples are discussed, and directions for future research are pointed out.
Breeding systems in the lichen-forming fungal genus Cladonia.
The plot thickens: haploid and triploid-like thalli, hybridization, and biased mating type ratios in Letharia
It is proposed that Letharia fungi are heterothallic and typically haploid, and evidence that triploid-like individuals are rare hybrids between L. lupina and an unknown Letharia lineage is provided, reconciling classic systematic and genetic studies with recent genomic observations.


The Evolution of the Selfing Rate in Functionally Hermaphrodite Plants and Animals
The occurrence of selfing and mechanisms for its avoidance, in functionally hermaphrodite animal and plants and theories for the advantages and disadvantages are reviewed.
Physiological Ecology of Lichens
The lichen environment: temperature, moisture, and ionic criteria; the interaction between net photosynthesis, light and temperature; and phoneotypic plasticity and differential strategies.
Reproductive Modes of Lichens in Stressful Environments in Central Ellesmere Island, Canadian High Arctic
Abstract Lichens of the most highly stressful habitats in Sverdrup Pass, Ellesmere Island, Northwest Territories, Canada, were examined for reproductive structures, as were lichens of less extreme
Use of Randomly Amplified Polymorphic Dna Markers as a Tool to Study Variation in Lichen-Forming Fungi
RAPD-PCR fingerprints of Graphis scripta, G. elegans and Phacographis dendritica were successfully generated using this protocol and individual isolates could be identified on the basis of differences in banding patterns produced.
Evolution of sex
The Economy of Nature and the Evolution of Sex*. By Michael T. Ghiselin. Pp. xii + 346. (University of California: Berkeley, Los Angeles and London, December 1974.) $12.05; £7.10.
DNA Fingerprinting in Plants and Fungi
A comparison of Methods for Detecting Genetic Variation and Applications of DNA Fingerprinting in Plants and Fungi and the Spectrum of DNA Typing Strategies is presented.
Plant Breeding Systems
This illustrated book attempts to provide a unified and comprehensive coverage of plant breeding systems, a subject vital to plant geneticists, plant breeders, taxonomists, evolutionists and