438 Chapter 8.4 SOME PECULIAR OBSERVATION District Tehri Garhwal presents a rich & diverse Pteridophytic because of varying elevations, along with tropical to alpine climate prevailing over the region. During the floristic study of ferns of the study area, Tehri Garhwal, some peculiar characters were observed. Only few of the ferns exhibiting these special characters were observed. These special characters are as follows: a) Froking of fronds b) Insect feeding c) Rooting nature a.) Forking of fronds: During the exhaustive field survey, it was observed that some polymorphic variation were present in two species of ferns, in the study area. This may be due to their adaptability toward unfavourable environment, such as external stress due to wind velocity, soil type, light, elevation, anthropogenic activities etc. Manickam and Rajkumar (1999) has done a lot of work on the fern flora of Western ghats, revealing that the polymorphism could be seen in varied range in the ferns frond. In the present study Forking of frond was observed in Microsorium membranaceum & Lepisorus clathraus. In L. clathratus forking was observed at 1/3 the length of lamina, whereas in case of M. membranacemm, forking observed very close to the tip (Plate 8.4a). b.) Insect feeding: Ferns also exhibits a unique relationship with the insects. Ferns play a vital role in feeding the insect, their shelter and as a site for laying eggs. Insect Phytphagy of ferns was also by many workers (Leeuwen, 1938; Pande & Pande 1991, 2002; Bera et al., 1994, Pande et al. 2009). During the present investigation, ferns-Insect interrelationship was observed in three species, Dryopteris carolihopei, Pseudocyclosorus canus & Tectaria coadunata (Plate 8.4b). Dryopteris carolihopei- On crictical examination, insect feeding was observed on the abaxial surface of the lamina. Sori were completely ingested, making a hole in the Estelar
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438
Chapter 8.4 SOME PECULIAR OBSERVATION
District Tehri Garhwal presents a rich & diverse Pteridophytic because of varying
elevations, along with tropical to alpine climate prevailing over the region. During the
floristic study of ferns of the study area, Tehri Garhwal, some peculiar characters were
observed. Only few of the ferns exhibiting these special characters were observed. These
special characters are as follows:
a) Froking of fronds
b) Insect feeding
c) Rooting nature
a.) Forking of fronds: During the exhaustive field survey, it was observed that
some polymorphic variation were present in two species of ferns, in the study area. This
may be due to their adaptability toward unfavourable environment, such as external stress
due to wind velocity, soil type, light, elevation, anthropogenic activities etc.
Manickam and Rajkumar (1999) has done a lot of work on the fern flora of Western
ghats, revealing that the polymorphism could be seen in varied range in the ferns frond. In
the present study Forking of frond was observed in Microsorium membranaceum &
Lepisorus clathraus. In L. clathratus forking was observed at 1/3 the length of lamina,
whereas in case of M. membranacemm, forking observed very close to the tip (Plate
8.4a).
b.) Insect feeding: Ferns also exhibits a unique relationship with the insects. Ferns
play a vital role in feeding the insect, their shelter and as a site for laying eggs. Insect
Phytphagy of ferns was also by many workers (Leeuwen, 1938; Pande & Pande 1991,
2002; Bera et al., 1994, Pande et al. 2009). During the present investigation, ferns-Insect
interrelationship was observed in three species, Dryopteris carolihopei, Pseudocyclosorus
canus & Tectaria coadunata (Plate 8.4b).
Dryopteris carolihopei- On crictical examination, insect feeding was observed on
the abaxial surface of the lamina. Sori were completely ingested, making a hole in the
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lamina, also leaving a white spider web like structure on the surface of lamina along the
sori: similar structure was reported by Pande & Pande, 1991 in Pronephrium nudatum.
Pseudocyclosorus canus- A similar study of feeding of sori was reported in P.
canus. In this case sori were completely feeded leaving a white structure but there was no
hole in the surface of lamina.
Tectaria coadunata- In Tectaria coadunata insects were observed on the adaxial
surface of lamina. In T. coadunata sori were intact, but there were marks of feeding of
lamina.
c.) Budding nature of ferns: During the study small buds were observed. These
buds were present on the apical region of the fronds, attached terminally or sub terminally
on the rachis, which serves the purpose of vegetative reproduction. Where these buds get
detached from the main plant body, it give rise to a new individual nearly the mother
plant, that is why this group of fern is known as working fern (Plate 8.4c).
Following ferns from the study area, exhibiting budding nature are:
a) Polystichum lentum
b) Woodwardia unigemmata
c) Ampelopteris prolifera
d) Adiantum incisum
e) Adiantum edgeworthii
f) Adiantum philippense
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SUMMARY
Pteridophytes form the conspicuous element of the vegetation of the Himalaya and
provide a link with higher vascular and lower non-vascular plants. During this investigation
a detailed study on the fern-flora of district Tehri Garhwal has been worked out which has
proved to be of very much importance to the flora of Tehri district of Garhwal Himalaya in
particular and North-western Himalaya in general. Tehri Garhwal is one of the western
most mountainous districts of the Uttarakhand State, located on the outer ranges of the mid
Himalayas which comprise low line peaks rising contiguously with the planes of the
northern India. The district lies between the parallels of 30º 03' and 30º 53' north latitude
and 77º 56' and 79º 04' east longitudes.
The plan followed in the present manuscript is the Introduction followed by a short
account of Geographical location, Geology, Soils, Climate, Vegetation, Previous
exploration, Systematic treatment, Ecology and Ethnobotanical notes of the study area. The
present work records 154 species of fern belonging to 55 genera and 28 families,
constituting 15.4% of total fern flora (1000 species cf. Dixit, 1984) of India.
The rock units exposed in various parts of Tehri Garhwal district are classified in
two broad geotectonic zones viz. Central or Higher Himalaya and Lesser Himalaya. The
Central Himalaya lies to the north of Main Central Thrust (MCT) whereas the Lesser
Himalaya occurs to the south of it. Major soil type of the study area is Hilly Soil, developed
from graniteferous biotite, sctics granites, gnesiss, phyllites. These are brown to dark
grayish in color and slightly acidic (pH 5.80 to 6.27) in reaction. The climate in Tehri
Garhwal district varies from cold temperate, tropical to sub-tropical. Mean maximum
temperature of the district is 36.5ºC and mean minimum temperature is 4.6ºC. Relative
Humidity in the area increases rapidly with the onset of monsoon and reaches maximum (85%)
during August, while Relative Humidity is minimum (25%) during May. The average annual
rainfall (AAR) of the district is 1395 mm.
Forest types of Tehri Garhwal is based on Mehra et al. (1971) and arranged
according to Champion and Seth classification of forest type of India (1968). The
vegetation of District Tehri Garhwal is greatly modified due to many natural factors. With
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the change in the forest and its types, the different plants species of different groups also
varies. District Tehri Garhwal harbours Tropical, Subtropical, temperate, subalpine to
alpine type of vegetation. Major forest types of the district are- Chir-Pine forest, Oak mixed
forest and coniferous forest. Diversity of ferns is high in subtropical and temperate forests,
whereas in the tropical and alpine region diversity of ferns is too meager.
The present work deals with the systematic treatment of ferns and is the result of
four year (2008-2012) of continuous exhaustive explorations done in different localities of
District Tehri Garhwal. As per the standard protocol suggested by Jain and Rao (1977),
collection of plant, pressing and herbarium preparation was done. The collected plant
species were identified with the help of taxonomic revisions, monographs and relevant
floristic account and later confirmed by consulting the esteemed herbaria (DD, BSD) of the
region.
Detailed field data such as locality of plant, habit, habitat, size, colour,
frequency of occurrence, ecology, phytogeography and ethnobotany, etc. were recorded
during the survey and collection tours. The details of rhizome, stipe, lamina, sporangia and
spore were also observed. Macroparts and microparts of plant, (rhizome, lamina, stipe,
pinna, pinnule, etc.) were also studied from unmounted duplicate specimens. Surface
sculpture of spore was also worked out with the help of Scanning Electron Microscope
(SEM) for identification of closely allied taxa. A total of 90 illustrated photo plates of its
kind showing details of micro and macro parts of plants were prepared for Indian
Himalayan ferns, about 20 plates of natural photographs of the plants and 5 plates of
scanning electron microscopic photographs were also appended.
In presentation of systematic treatment of fern species, the families are arranged
according to classification of Pichi-Sermolli (1977), with minor modification based on
Ching (1978). Bracketed keys for the identification of families, genera and species have
been prepared. However, the genera within each family and species within a genus is
arranged alphabetically. A detailed description of the taxon along with the correct name,