Basidiomycota - Spore stage chart

Spore Stage #0 — Sorus name

Spermagonium/Pycnium

Spore Stage #1 — Sorus name

Aecium

Spore Stage #2 — Sorus name

Uredinium

Spore Stage #3 — Sorus name

Telium

Spore Stage #0 — Spore name — N, N+N, or 2N

Pycniospores → N

(receptive hyphae + spermatium)

Spore Stage #1 — Spore name — N, N+N, or 2N

Aeciospores → N+N

Spore Stage #2 — Spore name — N, N+N, or 2N

Urediniospores → N+N

Spore Stage #3 — Spore name — N, N+N, or 2N

Teliospores → 2N

Spore Stage #4 — Spore name — N, N+N, or 2N

Basidiospores → N

Pycniospore Function

combine with receptive hyphae in pycnia and result in formation of N+N mycelium (plasmogamy)

Aeciospore Function

infect the primary host

Urediniospore Function

infect the host species on which they are produced (repeating stage)

Teliospore Function

produce N basidiospores (after karyogamy and meiosis) and serve as the survival stage

Basidiospore Function

infect aecial (alternate) host species to form pycnia

Where do the key sexual reproduction events happen:

→ Meiosis

→ Plasmogamy (cell fusion)

→ Karyogamy (nuclear fusion)

Plasmogamy → stage 0 in the pycnium

Karyogamy → stage 3 in the teliospore

Meiosis → stage 3