This presentation has been designed to give the foundation of taxonomy in general and Plant Taxonomy in particular as a matter of pleasure to explore the diversity of the plant world.

1. INTRODUCTION TO PLANT TAXONOMY
A presentation by
Dr. N.Sannigrahi,
Associate Professor, Department of Botany
Nistarini College, Purulia(W.B) India

2. PLANTS-AESOME BEAUTY OF NATURE
 The plant kingdom comprises up thousands of plants from the tiniest mosses to the tallest trees,
 From unicellular to multicelluar with high complex organization with degree of uniqueness,
 Distributed in diverse habitats from dry desert Tundra to arctic zone with a little bit cosmopolitan in
distribution,
 Broadly classified into algae, bryophytes, pteridophytes, gymnosperms & angiosperms,
 Species of all the living organisms are mainly classified into five main categories- Monera, Protista,
fungi, Plantae and Animalia
 Plantae constitute about 2, 79,000 species ,
 Mosses & liverworts have 15000 species, Ferns & their allies of 10000, Gymnosperms of 820 species
& angiosperms of 3,69,000 species,
 Angiosperms are broadly made of monocotyledons and dicotyledons,
 Number of monocotyledons species are--- and dicotyledons are –
 The beauty of plant diversity is a pleasure of appetite to all nature lovers and naturalists.

3. ARISTATOLE-THE GREAT PHIOSOPHER

4. TAXONOMY
• Taxonomy is the science that explores, describes, names, and classifies all organisms. In this
slide, I will highlight the major steps in the elaboration of this science that provides baseline data
for all fields of biology and plays a vital role for society but is also an independent, complex, and
sound hypothesis-driven scientific discipline.
• Theophrastus(372-287 B.C) is considered as the “Father of Botany”, C. Linnaeus is regarded as
the “Father of Modern Botany”,
• A.P. de Candolle (1813) used the term ‘Taxonomy’ in his famous book, Theorie elementaire de la
botanique. Here ‘Taxonomy’ comes from the word ‘taxis’ means ‘arrangement’ and ‘nomos ’
means ‘rules’ or ‘laws’.
• Plant taxonomy is the science that finds, describes, identifies, classifies, and names plants. The
term Systematics is applied to the study or description of variations among organisms in order to
formulate a classification system. Organisms thus arranged into groups enable a large population
to be categorized and understood. Plant taxonomy or Sytematics has undergone through four
major approaches of study. These could be summarized as:
• 1) Pioneer or Alpha: This phase was early periods that involved explorations and discovery of
new plants.
• 2) Consolidation: In this phase, the large amount of data collected was organized to understand

5. CAROLUS LINNEAUS(1007-1778)-Father of Binomial System

6. WHAT IS TAXONOMY
• 3)Synthesis: During this phase, the consolidated data and adequate plant material collected was
classified principally based on morphological characters. It attained its peak by late 1800’s and to
some extent still continues.
• 4) Experimental: Using different scientific tools and modern technology, the vast amount of
collected data interpreted in evolutionary or phylogenetic terms is being currently analyzed. This
phase is still evolving.
• OBJECTIVES
• i) to provide a convenient method for identification and communication;
• ii) to produce a coherent and universal system of classification;
• iii) to provide a single Latin “scientific” name to every plant and groups of plants in the world,
both living and fossil.
• iv) to maintain inventory of the world flora; and
• v) to demonstrate the evolutionary implications of plant diversity; There are four important
steps in taxonomy:

7. TAXONOMY-THE EPIC OF THE PLANT WORLD

8. STEPS OF TAXONOMY
• There are four important steps in taxonomy:
• 1. CHARACTERISATION ,
• 2. IDENTIFICATION ,
• 3. CLASSIFICATION ,
• 4. NOMENCLATURE .
• These are the primary activities of a taxonomist. Characterization is the basic requirement for
understanding the different parts of the organism. It is thus a description of the characters. By
comparing the characters of two or more organisms, it becomes possible to differentiate them.
This leads to identification. When two or more organisms have been differentiated (identified) by
their characters, it becomes necessary to group them into categories. This is essentially what
taxonomists do when they classify organisms. Once the identified organisms have been classified,
it becomes necessary to name them. Thus the process of taxonomy is a logical sequence of
knowing (1) the characters of the organisms; (2) identifying them on the basis of an understanding
of their characters; (3) classifying them into groups; and (4) providing them name.

9. ALPHA, BETAAND GAMMA TAXONOMY
• Taxonomy is basically a fundamental science but with the passage of time, it has been diversified
and categorically classified under the following headings:
• Alpha taxonomy:
 The alpha (α) classification is an analytical step in which species are identified, characterized, and
named following classical approach based on morphological observations.
 When new species are discovered at this level, they are named after the Linnaean taxonomy of the
binomial nomenclature.
 The person who publishes his work first is given priority.
 All kinds of issues are dealt with here.
• Beta taxonomy:
 Beta (β) classification refers to the placement of species in a natural system of hierarchical categories.
 This is based on the evaluation of common structural features and numerous features that are easily
observable.
 Therefore, the beta classification method refers to the search for a natural classification system.

10. ALPHA, BETAAND GAMMA TAXONOMY
• Therefore, each taxon has its own diagnostic function with reference to the basic parameters of natural
classification.
• Gamma taxonomy:
 The gamma (Ƴ) classification method refers to the analysis of intra-specific variability and the study
of evolution.
 Much attention has been paid to the causal interpretation of organic diversity, and the study of
speciation.
 But in reality, they overlap and integrate, making it very difficult to separate them.
 Few groups of animals have classifications that extend to gamma levels. Otherwise, the work is still in
alpha and beta levels in most groups.
• Omega Taxonomy:
• It is the ultimate perfect system that comprises the different aspects to bring all the components of
taxonomy under one umbrella to have the fragrance of taxonomy in the real sense.

11. HOW TO IDENTIFY THESE PLANTS?

12. IDENTIFICATION
• It is the determination of the group to which a specimen belongs. The process usually includes a
direct comparison of an unknown specimen with the already classified, circumscribed, and named
taxa.The process includes the use of keys-of various types, computer based methods and variety
of polyclave species. It is done by the following methods:
• i. The determination of the similarities and differences between two specimens,
• ii. The direct comparison of the features of a specimen in hand with those in keys in order to
arrive at a name,
• iii. The assignment of an unidentified taxon to a correct class in an established system of
classification,
• iv. The determination of a name for a particular specimen in relation to an established system of
classification,
• Mostly the morphological characters along with anatomy, phytochemistry, cytology, palynology
and molecular data are involved for the proper identification of the unknown specimen.

13. HOW TO NAME THESE PLANTS?

14. NOMENCLATURE
• Nomenclature is a very important constituent of plant taxonomy. It can be defined as the system
of naming an object particularly that of biological origin. We are aware that man has been
interested in plants since prehistoric times. The plants have been given names by tribes in their
own languages. These are called common or vernacular names.
• Arrangement of definite names to plants is called nomenclature & it involves the principles
governed by rules formulated and adopted by ICBN listed formally in a code .The major goal of
ICBN is to provide one correct name for each taxon-the unit of taxonomy.
• Although a number of rules are addressed in the nomenclature of plants but the binomial system is
based on C. Linnaeus(1707-1778), the Swedish naturalist in the first edition-Species Plantarum.
• The name comprises two parts-
• Generic name
• & Specific epithet following some rules.
• e.g. Oryza sativa L. of Rice

15. HOW TO CLASSIFY THESE PLANTS?

16. CLASSIFICATION
• Classification always follows identification. Thus when two or more groups of plants have been
differentiated (identified) from their characters, it becomes necessary to recognize their
relationships. This leads to placing the groups in defined categories. The end result of this leads to
the synthesis of a system of classification.
• Kingdom : Plantae Division : Magnoliophyta Class : Asteropsida Order : Asterales Family :
Asteraceae Genus : Helianthus Species : annuus. Classification is the arrangement of organisms
into groups having common characteristics. These groups are then arranged according to a
system. For example similar species of flowering plants are placed into a genus (plural, genera);
similar genera are grouped into families; families with common features are arranged into orders,
orders into classes and classes into divisions. Classification results in the placing of organisms
into a hierarchy of ranks or categories such as species, genera, and families and so on. Indeed,
classification is both, an information storage and retrieval system without which scientific
communication would be impossible.

17. PLANT KINGDOM-AT A GLANCE

18. SOME ACRONYMS USED IN TAXONOMY
• ICBN- International Code of Botanical Nomenclature
• ICNB- International Code of the Nomenclature of Bacteria
• ICVCN- International Code for Virus classification and Nomenclature
• ICZN- International Code of Zoological nomenclature
• IAPT- International association of plant taxonomists
• ICNCP- International code of the Nomenclature of Cultivated plants
• OTU- Operational taxonomic Unit
• NT- Numerical Taxonomy
• CNH- Central National herbarium

19. ACKNOWLEDGEMENT
• REFERENCES
• Google for images
• Advanced Plant Taxonomy by A. K. Mondal
• A text book of Botany- Hait, Bhattacharya & Ghosh
• Plant Taxonomy –O. P. Sharma
• Plant Systematics- Chittaranjan Mohanty
• Disclaimer: This presentation has been developed for the enrichment of online
learning resources without any financial interest. The author is grateful for all for
having the pleasure of uses of the content used in this presentation.

20. HOPE, YOU HAVE THE FLAVOR.THANKS A LOT.