2. 2
INDEX
PAGE NO.
INTRODUCTION 3
THE VALUE OF HERBARIA FOR PLANT CONSERVATION 4-5
PURPOSES OF HERBARIA 6-7
USES OF HERBARIA IN EDUCATION & TRAINING 7
SOME OF THE IMPORTANT HERBARIA 7-8
(BOTH NATIONAL AND INTERNATIONAL)
CONCLUSION 9
REFERENCES 10
3. 3
INTRODUCTION
A herbarium is a museum of preserved plants that are used
for botanical research. Each herbarium specimen is made up of a
dried plant, mounted on archival paper, and affixed with a label
providing descriptive data. Herbaria across the globe provide a
permanent record of the diversity of the Earth's flora.
About 1550,Cesalpini and his co-workers began quite
definitely to preserve the materials they studied , and since then
herbarium making became a great and interesting feature of
botanical work. All civilized Countries posses their own plant
collections (herbaria).The greatest herbarium of the world is at the
Royal Botanic gardens, Kew England, possessing about six million
specimens. A few herbaria are their in our country, The biggest
herbarium of our country is at the Indian Botanic Garden, Calcutta,
possessing about one million specimens.
Herberia is a source of knowledge about the flora of a
region or a locality or a country. It is very much useful in the study of
cytology, in studying the structure of DNA, chemotaxonomy,
numerical taxonomy, etc. It is also used as a reservoir of gene pool
studies. It provides the important materials for the anatomical
studies. It is also used as a data store which gives us a lot of
information about the various details about plants. The type
specimens present in the herbaria help in the correct identification
of plants. The morphological characters of pollens which are stored
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in the herbaria remain unchanged even up to 200 years. These are
the various uses and importance of herbaria.
The Value of Herbaria for Plant
Conservation
An often repeated statement is that “you must know what
you have before you can conserve it” …but how do you know what
you have in the first place? Field biologists have been working on
this question for literally hundreds of years by conducting
inventories, from general natural history inventories to small, highly
detailed plot studies of flora and fauna. These inventories result in
preserved specimens, which in the case of plants, are placed into
herbaria along with their associated original locality information.
Herbarium specimens then serve as documented proof of a plant’s
occurrence at a specific time and place. Herbaria have the
advantage over living collections that if well cared for, can last for
hundreds of years if not longer. Although living collections are
valuable for many purposes, they are expensive and difficult to
maintain in cultivation for long periods of time. It is the vast number
of preserved plants and their longevity in storage that make them
ideally suited for the purpose of archiving a host of information on
plants and their habitats.
Worldwide, herbaria contain approximately 300 million
specimens, nearly all with labels that include collection locality
information. The labels may also contain a variety of information,
such as ecology, flowering time, ethnobotany, geology, pollination,
fragrances, and dispersal. Other information can be gleaned from
herbarium labels such as which plants grew where over time and
when did a particular invasive plant invade a particular region.
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Herbarium label information is most often summarized and
published in floras and monographs, though its real potential of
biodiversity mapping is being realized through the accumulation of
its data on computers in combination with global information
systems. One of the most valuable outcomes of this type of work is
the ability to determine which areas are the most species-diverse or
rich in endemic-species, allowing them to be given higher
conservation priorities. A great challenge for herbaria, though, and
the biological sciences in general, is capturing plant label information
electronically so that it can be made widely available for
conservation purposes.
Perhaps of greatest importance, herbaria are potential
repositories of genetic information for every species of plant known
to science. Techniques are continually being refined to extract DNA
and other chemical information from plants preserved decades or
even centuries ago. Newer techniques of DNA extraction,
particularly amplification, allow for smaller and smaller pieces of
herbarium material to be required for genetic analysis, thus
preserving the herbarium specimens for other types of studies.
Recognizing that some traditional preservation techniques may
hinder the future extraction of DNA, herbaria and botanical gardens
are adapting and placing more emphasis on the collection of
materials in silica gel and cryopreservation of seeds and tissues.
Herbarium and herbarium taxonomists have contributed so
significantly to our understanding of Natural History that there is no
need to defend their existence. There is an urgent need to undertake
extensive and intensive explorations of all parts of the country. This
is possible and could be carried out very effectively if the Universities
start taking an interest in developing Herbaria.
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PURPOSES OF HERBARIA
Drying the specimens:
A twig with leaves and inflorescence or flowers is taken from a shrub
or from a tree while the specimen taken from an herb should contain
both the vegetative and reproductive parts. The specimen to be
dried is kept in between the folds of old news papers. The news
papers should be periodically changed until the specimen is
completely dried. The specimen is dried in a plant press. A plant
press consists of two boards tightened with straps with the news
papers containing specimens inside them. Thus the specimen is well
dried.
Mounting of specimens:
The dried specimens are pasted on herbarium sheets of size 41 cm x
29 cm. The process of attaching the dried specimens to the
herbarium sheets is called mounting of specimens. The mounted
specimens are sprayed with a fungicide like 0.1% of silver chloride. It
is protected from insects with the help of pesticides like naphthalene
and carbon disulphide. The heavy parts of plants like fruits and seeds
are put in packets and are attached to the herbarium sheets.
Type Specimen:
When a new name is given or suggested to a species, then the same
specimens of that type are deposited in a recognized herbarium.
These specimens are called type specimens. The family name is given
based on the type genus. These specimens are the most valuable
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part of a herbarium and hence they are handled with special care.
These specimens are stored in fire-proof cabinets.
If the herbarium specimens are stored with special care, then the
specimen can be in a good condition for a long time. The specimen
should be preserved from the attack of insects and fungi. Hence, the
specimens are treated usually with chemicals that can repel the
insects from the specimens. The herbarium specimens are always
accompanied with a label in which the description about the plant,
the botanical name of the plant, family name of the plant, habit,
place and date of collection of the plant and the name of the person
who collected the specimen are given.
Uses of Herbaria in Education & Training
1) provide material for teaching (botany, taxonomy, field botany,
plant communities;ethnobotany;
2) agriculture; dendrology,forestry);
3) promote appreciation of botanical diversity by making specimens
available for viewing by students,
4) researchers,and the public.
5) provide internship and job opportunities for undergraduate and
graduate students
6) provide opportunities for students and young scientists to meet
more established scientists;
7) expose students to systematic research;
8) train local volunteers for specimenhandling, scanning, and
databasing etc.;
9) run education courses for the public (e.g. local plant families);
Some of the important Herbaria (Both national and international)
Herbarium of Royal Botanical Garden – Kew, London in England
- More than 60,00,000 specimens
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Herbarium of Indian Botanical Garden- Kolkata, India - More
than 10,00,000 specimens
Botanical Survey of India - Coimbatore, Tamil Nadu- More than
1,90,000 specimens
Presidency College Herbarium - Chennai, Tamil Nadu - More
than 10,000 specimens
Rapinat Herbarium - Trichy, Tamil Nadu - More than 12,000
specimens
Kew garden Herbarium Library
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CONCLUSION
Herbaria are essential for the study of plant taxonomy, the
study of geographic distributions, and the stabilizing of
nomenclature. Thus, it is desirable to include in a specimen as much
of the plant as possible (e.g., flowers, stems, leaves, seed, and fruit).
Linnaeus's herbarium now belongs to the Linnean Society in England.
Specimens housed in herbaria may be used to catalogue or
identify the flora of an area. A large collection from a single area is
used in writing a field guide or manual to aid in the identification of
plants that grow there. With more specimens available, the author of
the guide will better understand the variability of form in the plants
and the natural distribution over which the plants grow.
As a fundamental tool for plant taxonomy, herbaria play
other roles in plant conservation efforts. The simple act of correctly
identifying a plant species is necessary for conservation, providing
the language (Latin names) for biologists of far-flung regions and
ethnicities to be able to accurately communicate with each other.
Herbaria facilitate taxonomic studies by enabling collections from
diverse habitats and localities to be studied in one place. Plant
species vary in size and shape across their geographical range, and
this variation can be observed and studied easily in a herbarium.
Herbaria also serve as a place to deposit voucher specimens from
scientific studies where the correct identification of a plant is
essential.
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Considered as relics of the past by some biologists, there is a
renewed appreciation in the vast amount of information stored in
herbaria and its potential to help us understand, and conserve life on
earth.
REFERENCES
1. Pandey,B.P (2009).Taxonomy of Angiosperms: S.Chand &
companyLTD. New Delhi. P.P 76-80
2. http://botany.si.edu/documents/2003_Funk_100Uses.pdf
3. http://www.selby.org/learningandgrowing/articles/value-
herbaria-plant-conservation