Understanding Reproduction in Chytridiomycota
Martha J. PowellThe University of Alabama
But mostly asexually
How do They Do It?
Asexual Reproduction in Chytridiomycota
Asexual reproduction
zoospores in sporangiaautospores in sporangiafragmentation- polycentrics and
resting spores
Some resting spores (resting sporangia) my arise asexually
Vegetative stage is haploid
Asexual Life Cycle
Pollen
Zoospores
Septosperma sp. Resting Spores
Fragmentation
Powell & Blackwell 1991
Inoperculate Discharge
1% Toluidine Blue
Powell 1976
“Operculomyces sp.” JEL 223
Operculate Discharge
Sexual Reproduction in Chytridiomycota
Recombination has been reported via multiple techniques
Oogamous with motile spermPlanogametic copulationSomatogamy = rhizoidal fusionGametangial contact & copulation
Verification more limited
Meiosis is zygotic
Resting Spores Arise Asexually and Sexually
Thick Wall
Lipids
Glycogen
Reduced hydration
Germination typically prosporangium
Monoblepharis
MonoblepharidomycetesOogamous with motile sperm
Sparrow 1933 Shanor 1942
Marek 1984
ChytridiomycetesSomatogamy = rhizoidal fusion
Chytriomyces hyalinus MP004
Chytriomyces hyalinusMP 004
> 7 days
> Viewed on PmTg agar
> 10X and 20 X
CT
Resting spores are small
Can also form asexually
SomatogamyChytriomyces hyalinus
Moore and Miller 1973
Miller 1977
Polyphagus euglenae
Gametangial contact
Wager 1913
Polyphagus euglenae
Gametangial copulation
Canter 1967
Doggett and Porter 1996
Zygorhizidium planktonicum
Concepts
• Individuals – asexual versus sexual
• Nutritional stress
• Survival strategysizehydration (hydrolytic enzymes)storage
Thanks to National Science Foundation
• PEET Award #0529694Phylogenetic and Monographic Research on Spizellomycetalean Chytrids (Chytridiomycota)
• PEET Award #9978094 Monographic Research on the Zoosporic Fungi, Chytridiomycetes