Relative merits and demerits of major systems
of classification: Takhtajan , Bassaey ,
Hutchinson
Presented by : Panchal Rita C.
M.sc sem : 2
Department of Life sciences,
H.N.G.U., Patan

Content
Takhtajan Systems Of Classification.
Bassaey Systems Of Classification.
Hutchinson Systems Of Classification.

Takhtajan Systems Of Classification
Takhtajan ( 1910 to 2009 ) proposed
evolutionary system of classification in "
system and phylogeny of Flowering Plants
(1966)" and revised in 1987.
The latest revised edition of his classification
published in " Diversity and Classification of
Flowering Plants ( 1997)".
His latest classification is according to ICBN.

Merits
Dicots discussed prior to monocots.
Dicots begin with most primitive living
angiosperm Magnoliales.
The families are small and homogeneous units
made up of closely related genera.
Cyperaceae and Gramineae are placed under
separate orders.

Demerits
The main demerits is extremely narrowly
defined taxa , that has resulted in the un
warranted splitting of the related groups.
For example Papaveraceae kept away from
order Capparales.
Malvales have 10 orders , but based on
palynology , embryology these can be
divided into two orders Malvales and
Tiliales.

Bassaey Systems Of Classification
Bassaey ( 1845 - 1915 ) a student of Asa
Gray was the first American Taxonomist to
introduce phylognetic system of
classification.

Merits
The Gymnosperm which stand between the dicots and
Monocots in Bentham and Hooker's system have not
been considered.
Order Asismatales among monocots and Ranales among
dicots are placed at the base , because these two orders
have been regarded as most primitive.
Similarly Orchidaceae and Composite have been placed
at the top , because of their being most advanced
among monocots and dicots respectively.

Demerits
Placing of monocots before dicots is not justified.
Inclusion of families are Typhaceae ,
Sparganiaceae, Pandanaceae in Alismatales is not
sound , as these families are supposed to be
derived from Liliaceous ancestors.
Similarly Najadaceae is placed under Tiliales.The
family is more allied to Helobiales rather than
Liliales.

Hutchinson Systems Of Classification
He proposed a phylogenetic system of
classification in his " The Families of
Flowering Plants.”
He published his revised classification in "
British Flowering Plants."

Merits
It is most phylogenetic system of classification
based on natural characteristic of Plants.
Cytological, anatomical, paleobotanical ,
studies have been considered for treatment of
families.
Placing of gymnosperm before angiosperm in
Flowering plants.
Many Families have been raised to the rank of
orders legumiosae family raised to order
Leguminales.

Demerits
It is based on habit only and Lamiaceae and
Verbenaceae are placed away from each other.
There is no hypothesis for pro angiosperms.
Magnoliaceae mentioned as most primitive family
and according to other authors Winteraceae is the
most primitive family which vessel less.
In herbaceae , Lamiaceae is regarded advanced over
Asteraceae . Infact Asteraceae have been treated as
most advanced family of dicotyledons.

Reference
Text book of Botany Angiosperms by:
B.P.Pandey
https:// en.m.wikipedia.org
https://www.slideshare.net

Thank You