Reproductive Terminology of Fungi
- An asexual or mitotic reproductive stage in a pleomorphic life cycle that also includes a
teleomorph or meiotic reproductive stage.
- A nucleus with a chromosome number that is not an exact multiple of the normal haploid
number (2N+1, 2N-1, etc.)
- Fusion of motile gametes that are unequal in size; occurs in some Chytridiomycetes, not in
any plant pathogenic fungi.
- With two alleles for incompatibility; the inbreeding level and outbreeding level in biallelic fungi
are both 50 percent.
- With incompatibility between homokaryons controlled by one pair of alleles; a single
dikaryon gives rise to two different mating types; also referred as unifactorial.
- compatibility type
- A diploid stage that produces compounds that stimulate the development of gametangia in the
other compatibility type; occurs in oomycetes.
- Having the ability to fuse together and give rise to heterokaryons.
- Fusion between non-motile cells that can function as gametes or conidia and specialized
female structures; occurs in ascomycetes.
- Having two types of diploid individuals, some with male gametangia only and some with
female gametangia only; occurs in oomycetes, not in any plant pathogenic fungi.
- A fungal stage in which all cells contain two nuclei; dikaryons may be homokaryotic or
- A fungal stage in which the nuclei contain two genomes (2N). Diploid nuclei maybe
homozygous or heterozygous.
- gametangial contact
- Fusion between an antheridium and an oogonium followed by fertilization of oospheres by
antheridial nuclei; occurs in oomycetes.
- gametangial fusion
- Fusion between morphologically similar gametangia to form a zygote that develops into a
zygospore or an ascus; occurs in zygomycetes and lower ascomycetes.
- A fungal stage in which the nuclei contain one genome (N).
- heterogenic incompatibility
- Limiting of infertility to pairings of homokaryons that bring together like factors; these systems
operate independently of homogenic incompatibility systems.
- A fungal stage that contains nuclei of different genotypes.
- A fungal stage with cytoplasm from different individuals following plasmogamy.
- Self-sterile; a dikaryon or diploid results from fusion of compatible mating types.
- The whole fungus consisting of all mitotic and meiotic stages in the life cycle.
- holomorph diversity
- A paradigm based on the concept that recognizes meiotic, pleomorphic, and mitotic fungal
- homogenic incompatibility
- Limiting of interfertility to pairings of homokaryons that bring together different alleles at the
incompatibility loci (different mating types).
- A fungal stage in which all nuclei are of the same genotype.
- Self-fertile; a dikaryon or diploid develops from single meiospores.
- The level of compatibility between homokaryons derived from one dikaryotic or diploid
parental genotype following meiosis.
- Lacking the ability to undergo fusion and form heterokaryons.
- Fusion of morphologically identical motile gametes; occurs in myxomycetes and
- Fusion of haploid nuclei to form a diploid stage.
- mating type
- A homokaryotic haploid stage that will produce a diploid or dikaryotic stage only after
pairing with a compatible mating type.
- A spore that results directly from karyogamy and meiosis and consequently is characterized
by genetic recombination.
- meiotic holomorph
- A fungus for which the only known reproductive stage is a meiotic or sexual stage.
- A spore that results directly from mitosis and consequently is not characterized by genetic
- mitotic holomorph
- A fungus for which the only known reproductive stage is a mitotic or asexual stage or two or
more mitotic stages.
- monoecious or hermaphroditic
- With both male and female sex structures on the same individual.
- A fungal stage in which all cells contain a single nucleus.
- With a series of alleles at the locus or loci for incompatibility in a heterothallic species;
multiallelic systems restrcit inbreeding and enhance outbreeding and are known in
myxomycetes and basidiomycetes only.
- Fusion of motile sperm and non-motile egg; occurs in some chytridiomycetes, not in any
fungal plant pathogens.
- The level of incompatibility between homokaryons derived from different dikaryotic or
diploid parental genotypes following meiosis.
- parasexual cycle
- A nuclear cycle that results in recombinant haploid genotypes without meiosis; it involves
heterokaryosis, karyogamy to produce heterozygous diploid nuclei, and mitotic crossing over
and/or nondisjunction and aneuploidy.
- Fusion of cells to bring nuclei and cytoplasm from two different individuals together in the
- pleomorphic holomorph
- A fungus with a meiotic or sexual reproductive stage and one or more mitotic or asexual
- primary homothallism
- A condition in which a mating system is operating but two nuclei of compatible mating types
are incorporated in each meiospore; the spores are therefore self fertile.
- A hard vegetative resting structure consisting of thick-walled, usually pigmented, modified
- Fusion of morphologically undifferentiated somatic cells; the method of sexual reproduction in
basidiomycetes except rusts and smuts.
- Fusion of non-motile spermatia with specialized female reproductive structures; occurs in
rusts ans some ascomycetes.
- Term of individual anamorphs of pleomorphic species with two or more anamorphs.
- A sexual or meiotic reproductive stage ina pleomorphic life cycle that also includes one or
more asexual or mitotic reproductive stages.
- With incompatibility controlled by two pairs on non-linked alleles that segregate
independently at meiosis; a single dikaryon gives rise to four different mating types; all
tetrapolar systems are multiallelic and known in basidiomycetes only; also referred as
- universal holomorph
- A paradigm based on the concept that a morphologically expressed sexual or meiotic state
will eventually be found for all fungal species.
- vegetative incompatibility
- Limiting of interfertility to pairings of homokaryotic, diploid, or
dikaryotic vegetative stages that bring together like factors; a type of heterogenic incompatibility.