Relative merits and demerits of major systems
of classification: Takhtajan , Bassaey ,
Presented by : Panchal Rita C.
M.sc sem : 2
Department of Life sciences,
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.
Dicots discussed prior to monocots.
Dicots begin with most primitive living
The families are small and homogeneous units
made up of closely related genera.
Cyperaceae and Gramineae are placed under
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
Malvales have 10 orders , but based on
palynology , embryology these can be
divided into two orders Malvales and
Bassaey Systems Of Classification
Bassaey ( 1845 - 1915 ) a student of Asa
Gray was the first American Taxonomist to
introduce phylognetic system of
The Gymnosperm which stand between the dicots and
Monocots in Bentham and Hooker's system have not
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.
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
Hutchinson Systems Of Classification
He proposed a phylogenetic system of
classification in his " The Families of
He published his revised classification in "
British Flowering Plants."
It is most phylogenetic system of classification
based on natural characteristic of Plants.
Cytological, anatomical, paleobotanical ,
studies have been considered for treatment of
Placing of gymnosperm before angiosperm in
Many Families have been raised to the rank of
orders legumiosae family raised to order
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.
Text book of Botany Angiosperms by: