higher secondary - first year - botany - Textbooks Online

Fungi
Myxomycota Eumycota
Plasmodio
phoromycetes
Myxomycetes
Traditionally fungi have been regarded as
plants. At one time fungi were given the status of
a class and together with the class algae formed
the division Thallophyta of the Plant Kingdom.
The thallophyta were those plants whose bodies
could be described as thalli. A thallus is a body,
often flat, which is not differentiated into true roots,
stem and leaves and lack a true vascular system.
A modification of the scheme of classification of
fungi proposed by Ainsworth(1973) and adopted
by Webster(1980) is outlined below.
Division Myxomycota: They lack cell wall and
are quite unusual organisms. Possess either a
plasmodium, a mass of naked, multinucleate
protoplasm, which feeds by ingesting particulate
matter and shows amoeboid movement, or
pseudoplasmodium, an aggregation of separate
amoeboid cells. Both are of a slimy consistency,
hence they are also called “Slime moulds”. It
includes three classes.
Division Eumycota: True fungi, all with cell
wall. It is customary to recognize five subdivisions
under this division.
A. Mastigomycotina: These are zoosporic
fungi, many are solely aquatic. Three classes are
included in this, each characterized by their
distinctive type of zoospores.
B. Zygomycotina: Vegetative body
haplophase. Asexual spores are non-motile spores.
Sexual reproduction takes place by the complete
fusion of two multi-nucleate gametangia producing
a zygospore. Because of this the fungi of the class
zygomycetes are also known as conjugation fungi. Cell wall is made up of
chitin and chitosan. It includes two classes. The common black, bread
moulds Rhizopus and Mucor belong to this group. Rhizopus is a very
common saprotroph similar in appearance to Mucor, but more widespread.
Acrasiomycetes
Deuteromycotina
Basidiomycotina
Ascomycotina
Zygomycotina
Mastigomycotina
Fig. 1.12. Classification of Fungi by Ainsworth
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