Biological Classification
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BÅSÏDÏØMÝÇËTËS
1.
Includes mushrooms, bracket fungi or puffballs. (AIPMT 2007)
2.
They grow in soil, on logs and tree stumps and in living plant bodies as
parasites (e.g., rusts and smuts).
3.
The mycelium is branched and septate.
4.
The asexual spores are generally not found, but
vegetative reproduction by fragmentation is common.
5.
The sex organs are absent, but plasmogamy occurs
by fusion of two vegetative or somatic cells of different
strains or genotypes.
6.
The resultant structure is dikaryotic which gives rise
to basidium. Karyogamy and meiosis take place in
basidium producing four basidiospores. Basidiospores are exogenously
produced on the basidium. Basidia are arranged in fruiting bodies
(basidiocarps). E.g. Agaricus (mushroom), Ustilago (smut) and Puccinia
(rust fungus).
DËÜTËRØMÝÇËTËS
1
2
When the perfect (sexual) stages of these fungi were
discovered they were moved into other classes (often to
ascomycetes and basidiomycetes)
Commonly known as imperfect fungi because only the
asexual or vegetative phases of these fungi are known.
(AIPMT 2015)
3
4
They reproduce only by asexual spores (conidia).
It is also possible that asexual and vegetative stage have
been given one name (and placed under deuteromycetes)
and the sexual stage another (and placed under another
class). When the linkages were established, the fungi were
correctly identified and moved out of deuteromycetes
5
6
Some are saprophytes or parasites. Majority are
decomposers of litter and help in mineral cycling.
E.g. Alternaria, Colletotrichum and Trichoderma.
The mycelium is septate and branched.