INTRODUCTION TO MYCOLOGY 1.1

Sexual

involves fusion of compatible nuclei from 2 parent cells

antheridium

male gametangia

oogonium

female gametangia

plasmogamy

karyogamy

meiosis

3 phases of sexual reproduction

plasmogamy

fusion of protoplasm

karyogamy

fusion of nucleus

meiosis

reductional nuclear division; diploid nucleus reduced to 4 haploid nucleus

gametic copulation

gamete-gametangial copulation

gametangial copulation

spermatization

4 various methods by which compatible nuclei are brought together in plasmogamy some are:

planogametic copulation

• motile gametes are called planogametes. The fusion of two gametes, one or both of which are called this.

isogamy

anisogamy

heterogamy/oogamy

3 types of planogametic copulation

isogamy

morphologically similar but compatible type of gametes unite to form a motile zygote

anisogamy

union of one larger gamete with another smaller gamete. The resultant zygote is motile.

The zygote resulting from isogamous or anisogamous planogametic copulation forms a ‘resting sporangium’

heterogamy/oogamy

non-motile female gamete is fertilized by a motile male gamete. This results in the formation of oospores, a resistant structure and resting spore

gametangial contact

in this methof the male gamete (antheridium) and the female gamete (oogonium) come in contact and one or more nuclei from the male gamete enter the female gamete, oogonium dissolved in the intervening wall through a pore or through a fertilization tube

gametangial copulation

a process of fusion of entire contents of the two mating gametangia

anisogametangial copulation

isogamous copulation

2 types of gamtangial copulation

anisogametangial copulation

fusion between unequal gametangia. the zygote forms a resting sporangium

isogamous copulation

two morphologically similar gametangial hyphae come in contact, the wall at the point of contact dissolves and the contents mix in the cell thus formed

spermitization

• some fungi rusts bear numerous minute non-motile uninucleate, male cells called spermatia

• spermatia are produced in spiral receptacles called spermagonia

• carried by insects, wind or water to the female gametangium, which is usually a special receptive hypha

• a pore develops at the point of contact and the contents of spermatium pass into the particular respective hyphae

trichogyne

a special receptive hypha

somatogamy

no sex organs are produced and somatic cells function as gametes. it is common in Asomycota and Basidiomycota fungi

Ascopores

Basidiospores

Zygospore

Oospores

4 types of sexual spores

Ascospores

non-meiotic spores produced inside specials sacs called asci; produced by members of ascomycota

Basidiospores

non-motile meiospore formed on short outgrowths of club-shaped structures called basidium

Zygospore

large, thick-walled spores formed at the tips of 2 sexually compatible hyphae; produced by members of zygomycota

oospores

spores formed within a specialized female structure after fertilization of eggs by male gametes formed in an antheridium