ao)
a ey. eee ry a
ere = Sie a
Sciex: Soy

*
o

me
¢.
-

ee

Fil EO i

THE BRITISH PTERIDOLOGICAL SOCIE} Pe
Officers and poms? from October 1994

President: ‘Dr ‘EG: Walker 2 ite
President Emeritus: J W. aes MBE

Vice Presidents: 4d Ee ee TAG Crabbe, Dr C. N. Page, M. Hi: Rickard, J R

Honorary General Sec retal ay
SGMDALCHIVISL: 1G a 16 nee Comer Road, Cantey,

_ Membership Secretary ae - | Rade ce nine
_ Editor of the Bulletin: 2 Department of Botany. 1 c he N

Treasurer:

Meetings Secretary:

-

Editors of the Fern Gazette: ey ; ie A. ‘Thomas, J La Crabb :

_ Editor of the Pteridologist:

Committee; Nees we ee RG. Akers, R Coe

*»

_ Spore Exchange Organiser:
Plant Exchange Organisers: = | at i

Booksales Organiser: S.J. Munyard, 234 Harold Resa pasa East su |
Trustees of Greenfield and Centenar y Jig unds: on . Busby, Dr N. th Hards, ‘

The BRITISH PTERIDOLOGICAL SOCIETY \ was founded i in 1891 and today ceinee
enthusiasts. It provides a wide range of information about ferns through the medium of its pu :
available literature. It also organises formal talks, informal discussions, field meetings, ga

exchanges, a spore exchange scheme and fern book sales. The posit has a wide 1 n

Fern Gazette, Pier chit) sid Bulletin, are pibuatcd hee The Fern Gazette ruins mi

of specialist interest on international pteridology, the Pter idologist, topics | of more nae as
Bulletin, serien business and meetings reports. 3 ?

the Fern Gazette £2. 50, }

FERN GAZ. 15(1)1995 l

RARE AND ENDANGERED FERNS OF THE WESTERN GHATS
OF SOUTH INDIA

V.S.MANICKAM
St.Xavier’s College, Palayamkottai-627002, Tamil Nadu, India

Key words: ferns, Western Ghats, India, forests, conservation

ABSTRACT

A general account of the ferns of the Western Ghats is given and reference made to
R.H.Beddome’s records from South India. The major hill-stations in Tamil Nadu and Kerala
south of Palghat Gap and the Nilgiris in Tamil Nadu and their forests are mentioned. The
occurrence of 46 rare and endangered species is described and notes given on their
conservation and ecology.

INTRODUCTION

The Western Ghats lie between 8° 22’ and 20° 40’ North at about 73° 77’ East and cover a
distance of 1600 km from the Tapiti valley in Gujarat State south to Kanyakumari in Tamil Nadu
state. This series of mountain ranges including the Nilgiri Hills, Anamallays Hills and Palni
Hills, run north-south along the West coast traversing the states of Gujarat, Maharashtra, Goa,
Karnataka, Kerala and Tamil Nadu. The otherwise more or less continuous hill ranges have a
major discontinuity at the Palghat Gap, separating the ranges of the Nilgiri Hills from the
Anamallays. The Ghats descend steeply in the west, facing the Arabian sea, whereas they merge
gradually through a series of hills with the Deccan plateau in the East. Anamudi, rising to 2695
m is the highest peak south of the Himalaya. The Western Ghats receive heavy rainfall both from
the south-west and north-east monsoons. The annual rainfall varies from 1000-5000 mm
depending on altitude. Various types of forest such as scrub-forest (200-500 m), moist
deciduous forest (500-900 m) and tropical moist evergreen forest (1200-1500 m) occur on the
hills. A characteristic feature of the Western Ghats is the occurrence of sholas (high altitude
forest with a distinct abrupt boundary and trees with short trunks) above 1500 m. They are found
in patches in hollows and sheltered folds surrounded by rolling downs in the Anamallays,
Nilgiris and Palni hills and in the high ranges of Kerala and Karnataka. The high plateaus above
of 1700-1900 m are covered with savannah with scattered shrubs. A remarkable floristic
diversity is evident from the fact that of about 15,000 species of flowering plants estimated to
occur in India, about 4,000 are found in the Western Ghats. There are 57 endemic genera in the
Western Ghats alone and 84 in the rest of India (Nair & Daniel 1986).

BEDDOME’S RECORD OF FERNS IN THE WESTERN GHATS

The earliest noteworthy work on the ferns of South India by Gustav Kunze (1851), who
recorded and described ferns from the Nilgiris Hills, was followed by the work of Colonel
Richard Henry Beddome (1864), Chief Conservator of forests for the entire Madras region, who
recorded 240 species from South India and 61 from Ceylon. Of the 240 south Indian species,
184 were from Tamil Nadu, 38 from Kerala, 6 from Karnataka and one from Andhra Pradesh.
Beddome also mentioned “ Western side” 11 times with no mention of particular locality. In his
Ferns of Southern India (1864), Beddome mentioned the Anamallays 83 times, Nilgiris 75
times, Palnis 15 times and Coimbatore Hills 11 times. It appears strange that Beddome who
recorded so many ferns from Anamallays and Nilgiris, did not refer to the Tirunelveli Hills from
where the present author has collected about 160 species, of which some are extremely rare in
South India.

The nomenclature used by Beddome was mostly based on that of the early British botanists,

2 FERN GAZETTE: VOLUME 15 PART | (1995)

notably Moore and Hooker, and particularly Baker in Hooker and Baker (1868) who generally
had broader species-concepts than today. According to the late Prof. R.E. Holttum (pers.comm.),
Beddome misapplied names for Indian ferns in quite a number of cases. However Beddome’s
works remain the most comprehensive important reference materials for understanding Indian
ferns today. The most important modern revision of much of Beddome’s work has been that of
Sledge (1956-1982) in various papers concerning Sri Lankan ferns, including a comprehensive
survey (Sledge 1982).

Although the author has been able to find nearly all of the species mentioned by Beddome
he has not seen the following six species which Beddome had recorded from the Western Ghats:
Osmunda collina Sledge, Lygodium circinnatum (Burm. f.) Sw., L. japonicum (Thunb.) Sw.,
Trichomanes bimarginatum v.d.Bosch, Pronephrium thwaitesii (Hook.) Holltum, Anogramma
leptophylla (L.) Link. Most of these species presumably escaped my notice, though it is also
possible that some could have been eliminated by the continuous destruction of primary forests
in the area. Beddome’s specimen of O. collina, however, may well not have originated in India,
but in Sri Lanka (see Sledge 1981:10-11).

THE AUTHOR’S FIELD WORK ON THE WESTERN GHATS

The author first carried out field work in the Palni Hills (from 1969-1975) based on Kodaikanal,
collecting 2,500 numbers consisting of 137 species and 13 so-called varieties (Manickam,
1986). The field work was intensive and extensive, covering practically all the forests on the
high plateau and on the northern, eastern and southern slopes. At that time there were not many
bus routes, and being without a personal vehicle, long distances were covered on foot on bridle-
paths from the high summits to the foothills, to collect ferns. On the high plateau the main
sholas explored were those around Berijam Lake, Kukal, Vembadi peak and the township
reservoir. There are dense sholas on the south western-border of the states of Tamil Nadu and
Kerala at around 2100 m, particularly on the Tamil Nadu side where the author undertook
several trips.

Following this period major field work on the Western Ghats was continued from 1984-87
when the ecology of ferns was particularly studied, inspired by the work of Professor Jan
Kornas. The area studied covered some 18,000 sq.kms south of the Palghat gap over a length
of 450 kms in both Tamil Nadu and Kerala. Altogether 134 days were spent in the field, covering
the area extensively on foot and realizing a total of 4058 collections. Very few primary forests
remain south of Palghat gap in the state of Kerala because of extensive cultivation of
economically useful crops. In the Western Ghats above 1500 m, there are 750 km2 of tea-
cultivation, 1500 km2 of coffee and 825 km2 of cardamon . The only primary forests in Kerala
which the author could explore are the undisturbed riparian forests west of Anamudi peak, a few
sholas north of Munnar, the forests within the Kerala border in Agasthiamalai and the forests
west of the Anamallays where a motor road runs from Valparai town in Tamil Nadu to Chalakudi
in Kerala. Mention should be made of Mackay’s path (36km) between Akkamalai in Tamil Nadu
and Munnar in Kerala. While trekking along this path, many large evergreen forests were
encountered and one very rare species, Vittaria flexuosa Fée, was also collected. The forests on
the way to Sabarimala are also intact from where the rare species Athyrium cumingianum (C.
Pres!) Ching. was collected. No forests were seen along the routes Munnar-Palai, Palai-
Thekkadi and Thekkadi-Allepy. There are still some forests in the Ponmudi hills near
Trivandrum on the western slopes and a few undisturbed sholas on the top.

The author has visitied vast stretches of primary forests in the Western Ghats of Tamil Nadu.
Even though the entire high plateau of the Anamallays, from Akkamalai on the east to Sholayar
Dam on the West, has been entirely converted for tea-plantation, there are still vast dense forests
east of Akkamalai (1800 m), both on the high plateau and on the slopes. Some rare species such
as Leptochilus thwaitesianus Fée, Elaphoglossum nilgiricum Kragina ex Sledge, Asplenium

FERNS OF THE WESTERN GHATS 3

ensiforme Wall. ex Hook. & Grev. and a few other, previously unreported species, were
collected from these forests. Beddome did not explore the Tirunelveli Hills, but the author has
collected about 160 species there, of which some are extremely rare in South India. The
Tirunelveli Hill ranges consist of the Agasthiamalai Range (1800 m), Kothayar Range (1500 m)
and Kalakad Range (1100 m) which are all close to each other. The Kalakad Range is a virgin
area with only a few acres of cardamon cultivation, the Agasthiamalai Range remains totally
undisturbed while there are a few hundred acres of tea cultivation in the Kothayar Range. In all
three there are dense moist forests where numerous fern-species occur luxuriantly. There are
also evergreen forests south of the Tirunelveli ranges and close to the of town Nagercoil around
the villages of Balamore (900 m), Maramalai (700 m) and Korimoni (900 m). Beddome made
a few records of ferns from the well-known tourist-spot, Courtallam, famous for its five-pronged
water-fall.

After a satisfactory survey of the southern parts of the Western Ghats, thorough exploration
was undertaken of the Nilgiris, north of Palghat gap. Field-work began in October 1991 and
ended in March 1992, totalling 65 field-days during which a total of 2200 field- numbers were
collected. The total area of the Nilgiris is 2549 km2, of which 1000 km2 is under cultivation of
tea and other economically useful crop plants. Dodabetta (2638 m) on the eastern summit of the
Nilgiris is the highest point. Nearly all the major forests and most of the small pockets of sholas
were explored in the 216 reserve-forests throughout the Nilgiris. Only Lamb’s Rock Shola, a
reserve-forest near Conoor, is close to areas of major habitation. There are a dozen sholas along
the road running from Ootcamund to Naduvattom (42 km). From this road two other roads
diverge, one leading to Governor Shola and the other to Terrace Estate. All the sholas along
these roads were explored, collecting some very rare species. On the high plateau there is a 203
km long circular road, passing through numerous villages and several sholas where fern-
collection was also carried out. Even though all the major sholas on the Kundha, Kottagiri and
Coonoor ranges were thoroughly explored, the fern diversity was not very high. The northern
slopes of the Nilgiris, where Muthumalai sanctuary is situated, are rather dry with no dense
forests. The high plateau is the wettest part of the Nilgiris and there are numerous fern-species
there. Out of 140 species collected from the Nilgiris, 75 were found in the sholas on the high

plateau.
Fifty five species of ferns were collected from the northern slopes of the moist Gudalur

range (1300 m). From the Nadugani area which is close to Kerala rare species such as
Pronephrium articulatum (Houlst. & Moore) Holttum, Pteris mertensioides Willd. and Pteris
longipes D.Don were collected. Collections were made on the eastern slopes from the top down
to the foothills along four different routes - via Kottagiri, via Coonoor,via Manjoor and via
Droog. Though the author’s fern-collection in the Nilgiris has been thorough, only one species,
Loxogramme parallela Copel., was found which was not collected from the Western Ghats
south of Palghat gap. Certain species rare in the south of India such as Asplenium erectum Bory
ex Wild. Swartz, Belvisia revoluta (Bl.) Copel., Diplazium dilatatum B1., Histiopteris incisa
(Thunb.) J. Smith, Humata repens (L.f.) Diels and Pronephrium thwaitesii (Hook.) Holttum, all
of which Beddome had recorded from the Nilgiris, were not collected again by the present
author. A comparison of the fern floras of the Nilgiris with that of the Palnis, which are similar
in altitude, area and climate would be of interest and will be dealt with in a separate paper.

CONSERVATION
Most fern species, being shade and moisture loving, grow in the interior of sholas and forests.
Any disturbance of the vegetation, even though not directly to the ferns themselves, will affect
the microclimate and lead to the destruction of ferns. When trees are felled, the epiphytes are
automatically destroyed with them. A number of epiphytic and lithophytic ferns on the Palni

4 FERN GAZETTE: VOLUME 15 PART | (1995)

Hills, which the author observed 22 years ago, are to be found no more in the same locations,
or perhaps even destroyed altogether, due to the removal of forest-cover. Ferns growing on
semi-exposed sites disappear when full sunlight is allowed in by cutting trees at the periphery
of forests. In certain riparian forests in the Palnis Diplazium brachylobum has been completely
eradicated due to the removal of trees to make way for banana-cultivation. Today most of the
sholas on the high plateau of the Palnis have been cleared for planting monoculture forests of
Pinus, Acacia, Eucalyptus etc. On the south-western slopes which are the wettest parts of the
Palnis, large areas of forests have been destroyed for cardamon cultivation which is particularly
destructive as, unlike for many other crops, planting occurs even right into the stream-gulleys
where it thrives and destroys these special refuges of ferns. Very rare species such as Diplazium
cognatum (Hieron.) Sledge, Microlepia majuscula (Lowe) T. Moore and Lastreopsis tenera
(R.Br.) Tindale were not found anymore in these areas during the author’s recent field- trips. The
cultivation of coffee, bananas and oranges on the north-eastern slopes has also led to the
elimination of moist deciduous forests there. Diplazium cognatum, a species restricted to Sri
Lanka and South India, and abundant on these slopes 15 years ago, was not found here recently
by the present author.

There are a number of developments that lead to the destruction of forests and, indirectly,
of the fern-flora. Trees are felled for wood-supplies to industry, for constructing multi-purpose
river-valley projects, for road-construction, for rehousing refugees etc. There are hundreds of
dams in the Western Ghats and 631 dams in Maharashtra alone. Ferns preferring semi-aquatic
habitats disappear when dams are constructed. The government spends millions of rupees in its
programmes ostensibly aimed at conserving forest-cover and yet, ironically, also allows big
agencies to fell-forest trees for industry. We have to discover balanced ways of preserving the
integrity of natural resources and of conserving certain key localities properly while working for
human-development and progress.

Many pteridophytes are very sensitive to microclimate changes and hence are of
considerable importance for understanding subtle changes in the environment. In evergreen
forests at medium (1500 m) and high altitudes (2000 m) in the Western Ghats ferns are the
dominant constituent of the ground-flora and hence any disturbance inflicted on them is sure to
affect the biological equilibrium in forest-ecosystems. In the Palni and Nilgiri Hills, where
human interference is enormous, forests are protected by fencing, and forest officers
periodically visit the forests in an attempt to prevent human interference. Apart from conserving
ferns in situ, certain very threatened species should also be preserved ex situ by cultivating and
propagating plants in gardens and green-houses at different altitudinal levels with a view to re-
establishing them in the wild. It is also important that field botanists avoid ruthlessly collecting
rare species and make sure that they leave the bulk of plants to continue to grow and reproduce
in the wild.

RARE AND ENDANGERED SPECIES
In the following list all the records given were collected by the author unless otherwise stated
as the collections represented in major herbaria have not so far been examined and included in
the survey.
1. Adiantum poiretii Wikstr. L.

Collected first under tea-plants at Munnar at 1800 m and later from the Naduvattom-
Gudalur road in the Nilgiris at 1700 m. It occurs in the sheltered parts of road- cuttings under
trees.

Distribution: India (Tamil Nadu and Kerala), Sri Lanka, Central and South America, Africa, East
African Islands. As stated by Sledge (1973: 154), this is the species reported by Beddome as A.
aethiopicum, the S. Indian sheets so- named at Kew being A. poiretii.

FERNS OF THE WESTERN GHATS 5

2. Athyrium cumingianum (C. Presl) Ching.

Three findings in Kerala and Tamil Nadu have been made. It was seen on the roadside at
~ Pamba (Kerala) at 900 m, on the roadside at Sabarimala in (Kerala) and in the Mnamboli range
in the Anamallays in Tamil Nadu at 800 m. In all cases it occurs on fully shaded earth- banks.
The serrate margin and the dark green colour of the simple pinnae are characteristic.
Distribution: India (Assam, South India), Sri Lanka, S. China, S.E. Asia and Japan.

3. Asplenium nidus L.

This is a beautiful epiphytic fern with glossy simple leaves forming a large basket found in
evergreen forests at 600-800 m. It was collected from a shola near Sabarimala, Anakundhi shola
at Top Slip in the Anamallays and at Ellamai valley and Manamboli forest in the Nilgiris.
Distribution: N.E. and S. India, China, Japan, S.E. Asia.

4. Asplenium ensiforme Wall. ex Hook.& Grev.

The only record made by the author is from the shola on the way from Akkamalai to Grass-
hill in the Anamallays at 1800 m. where it was found forming a dense tuft hanging from tree
trunks.

Distribution: Himalaya and S. India, Nepal, Bhutan, Burma, Sri Lanka, S. China, Thailand,
Vietnam.
5. Asplenium crinicaule Hance

A small epiphytic species collected in 1970 from tree trunks at Manalur coffee estate in the
Palnis at 1000 m, but now disappeared from this area. Later collected from Kadambarai forest
in the Anamallays.

Distribution: South India, E. Himalaya, China.

6. Asplenium polydon G.Forster

Collected in 1970 from Palamalai slopes in the Palnis, in 1984 from Kannikatty in the
Tirunelveli Hills and in 1992 from Mnamboli forest in the Anamallays. This species is a low
altitude (700 m), terrestrial or epiphytic fern, only reported by Beddome as A. falcatum Lam.
(See Morton 1967 and Sledge 1982).

Distribution: South India, Sikkim, Sri Lanka, Bangladesh, Malay Peninsula, Indonesia,
Australia, New Zealand, Africa, Polynesia, S. China, the Philippines.
7. Botrychium daucifolium Wall. ex Hook & Grev.

Collected from three different forests in the Palnis (1800 m), from the Kalakad Hills (1100
m) and from the sholas in the Coonoor and Kundha Ranges in the Nilgiris (1800 m). This
species, which had formed a large colony at the locality in the Kalakad hills, has now
disappeared from that site.

Distribution: N.E. India, Myanaung (Burma), S. China, Sri Lanka, Malay Archipelago,
Indonesia, the Philippines, Fiji.
8. Botrychium lanuginosum Wall. ex Hook.& Grev.

From 1969-71 several collections were made in the Palnis but this species is now a rarity as
the forests giving it shelter are mostly denuded. A single specimen was collected from a shaded
stream on the Ootcamund-Naduvattom road in the Nilgiris in 1992.

Distribution: N.W. and N.E. India, Nepal, Sri Lanka, Bhutan, Sumatra, Java, the Philippines,
S.W. China, Fiji.
9. Cheilanthes viridis (Forssk.) Sw.

Seen frequently on exposed roadsides at Upper Kothayar at 1500 m. It can be confused with
Pellaea boivini but, as pointed out by Sledge (1982), the pinna insertions are different in not
being articulated and the segments are more cuneate based.

Distribution: South India, Sri Lanka, Southern Africa, Mauritius, Réunion. Probably an
adventive alien in Sri Lanka and S. India.

6 FERN GAZETTE: VOLUME 15 PART | (1995)

10. Colysis hemionitidea C. Pres}

A species with simple, petiolate fronds and slight elongated sometimes partly confluent sori.
Collected from several forests in the Anamallays from 900 to 1300 m. It is only found on fully
shaded stream-banks.

Distribution: N. India, Nepal, Bhutan, Bangladesh, Malay Islands.
11. Cyathea crinita (Hook.) Copel.

Of the three species of Cyathea in South India, the other two being C. nilgirensis Holttum
and C. gigantea (Wall ex Hooker) Holttum, this is the rarest, growing in streams at 2200 m in
the Palnis and Nilgiris. Also seen in Silent Valley, near Munnar in Kerala. This fern is also
cultivated in the fernery of Sacred Heart College, Kodaikanal, its densely pale-scaley stripe and
rachis making it a most handsome, robust tree-fern, which is capable of surviving frosts.
Distribution: South India, Sri Lanka .

12. Diplazium beddomei C.Chr.

This species with shallow lobes on simple pinnules was collected from two places in Tamil
Nadu; Agasthiamalai (1500 m) and Upper Kothayar (1500 m). In both places it occurs on
completely shaded stream-banks.

Distribution: Endemic to South India and Sri Lanka. Sledge (1962) reported it only from Sir
Lanka.
13. Diplazium cognatum (Hieron.) Sledge

This species was observed on the eastern and southern slopes of the Palnis at 1100 m during
1971 but is now apparently totally absent there. However several plants were recently recorded
in the Sheikal Mudi forests in the Anamallays (1300 m).

Distribution: Endemic to South India and Sri Lanka. Sledge (1962) reported it only from Sri
Lanka.
14. Dryopteris juxtaposita Christ

It occurs on exposed stone-walls and among bushes on the high plateau of the Nilgiris (2300
m), It was collected in 1970 from the periphery of a shola near Munnar at 1800 m. A few plants
were also found growing on stone walls at the entrance of La Providence in Kodaikanal at 2300
m. Fraser-Jenkins (1989), who first recorded it from S. India found it quite commonly west of
Kotagiri in the Nilgiris and near Kodaikanal int he Palnis
Distribution: North India, Nepal, Bhutan, S.E. Tibet, S.W. China, Thailand, Vietnam.

15. Elaphoglossum nilgiricum Krajina ex Sledge

Two plants were collected by the author at Muzhiar in Kerala at 900 m and it grows
abundantly in a shola near T.R.Bazaar in the Nilgiris (2300 m). Two more records were made
from Akkamalai Forests in the Anamallays (1700 m). It is to be noted that this species was
recorded as terrestrial in Muzhiar and as epiphytic in the Nilgiris and Anamallays.
Distribution: Endemic to South India.

16. Grammitis attenuata Kunze

A very small lithophyte seen at the edges of forest streams from 800 m in the Ponmudi Hills,
Kerala, up to 2300 m in the Palnis. This species is likely to disappear from the Western Ghats
as its specialised, highly moist habitat is badly affected by the destruction of sholas.
Distribution: Endemic to South India and Sri Lanka.

17. Glaphyropteridopsis erubescens (Hook.) Ching

Seen in two localities. One was on an exposed stream-bank on the Sholayar-Chalakudi road
in the Anamallays at 1200 m, although these particular plants are likely to be crowded out by
the surrounding quick-growing flowering plants. The second was on a moist but exposed road-
side in the Mahendragiri forest at about 900 m.

Distribution: N. & S. India, Nepal, Bhutan, S.E. Tibet, China, Taiwan, the Malay Peninsula and
Islands.

FERNS OF THE WESTERN GHATS 7

18. Helminthostachys zeylanica (L.) Hook.

Has been observed by the author only in two localities, a Coconut groove in Thruvallam,
_ Trivandrum and at Keeriparai near Nagercoil, Tamil Nadu, at sea level. These two localities are
both in inhabited areas.
Distribution: N. India (from northern Pradesh easwards), Sri Lanka, Malay Peninsula, China,
Japan, the Philippines, Solomon Islands, New Caledonia, New Guinea, Australia.
19. Humata repens (L.f.) Diels

An extremely rare species collected by the author only from two localities, Muzhiar at 900
m and Kothayar at 1500 m. In Muzhiar it was an epiphyte whereas in Kothayar it was a large
colony on a partially exposed rock in the middle of a stream.
Distribution: South-east India, Malay Peninsula, and Islands, Australia, China, Japan,
Mascarene Islands.
20. Hypodematium crenatum (Forsk.) Kuhn subsp. crenatum

A wide spread old-world species, although only two records have been made by the author
in South India: one on an exposed stone wall at the entrance to Pannaikadu, in the Palnis, at
1400 m and another on the roadside at Yercaud Tamil Nadu. Fraser-Jenkins (nos. 9125-9127,
BM) found it more commonly in the Shevaroy Hills below Yercaud in 1978. It prefers a
calcareous substrate and is less common in its absence.
Distribution: C. India, The Himalaya, Nepal, Sri Lanka, S. China, Malay Peninsula, Indonesia,
E. Africa, Mauritius, Madagascar, Cape Verde Islands and Pacific Islands.

21. Hymenophyllum (Mecodium) denticulatum Sw.

Only a single site for this lithophyte is known to the author, on an exposed stream in a dry-
deciduous forest near Chalakudi in Kerala at 500 m. and Sledge (1968) also reported it from
only a single S. Indian collection.

Distribution: India (Meghalaya, Kerala), Bhutan, Myanaung (Burma), Java.
22. Hymenophyllum (Mecodium) javanicum Spreng.

Collected by the author from a single locality at Agasthiamalai (1500 m), growing on the
side of a bridle path in the evergreen forest.
Distribution: N. & S. India, Sri Lanka, Myanaung (Burma), Malay Peninsula, the Philippines,
Mauritius, Réunion, Australia, New Zealand.
23. Lastreopsis tenera (R.Br.) Tindale

Collected by the author in 1969 in the Vellagavi dry deciduous forest at 1100 m on the
southern slopes of the Palnis but not now seen here. However it also occurs abundantly in the
evergreen forest of the Kalakad hills at 1000 m.

Distribution: South India, Sri Lanka, the Phillppines, Indonesia, Taiwan, N. Australia, New
Caledonia, Fiji.
24. Leptochilus thwaitesianus Fée

This species is typically found on well shaded stream-banks in sholas from 1500 to 2000 m.
It was collected by the author from a shola at Devikolam (1500 m) and Grass Hill (1800 m).
Unlike L. decurrens, which occurs gregariously, this species is always solitary or only forms a
small colony. Its distinction from narrower forms of L. decurrens has been expounded in detail
by Sledge (1956).

Distribution: C. & S. India, Sri Lanka, Myanaung (Burma).
25. Lindsaea malabarica (Bedd.) Baker ex C.Chr.

A single plant of this was seen in the Upper Kothayar valley (1500 m). However, it grows
gregariously in a single spot in the Mathikettan shola of the Kolli hills at 1200 m in Tamil Nadu.
It was not seen by the author anywhere else in the Western Ghats.

Distribution: Endemic to South and S.C. India (Madhya Pradesh and Tamil Nadu).

8 FERN GAZETTE: VOLUME 15 PART | (1995)

26. Metathelypteris flaccida (B\.) Ching

The only locality found by the author in the Western Ghats is the Upper Kothayar valley
(1500 m) in the Tirunelveli hills in Tamil Nadu, where it grows on partially shaded stream-
banks.

Distribution: India (South India, Himalaya), Nepal, Sri Lanka, Java, the Philippines, S. China.
27. Microlepia majuscula (Lowe) T. Moore

Beddome (1864) recorded it from the Anamallays. Two new collections have been made
from the Palnis: on a cardamon estate on the southern slopes (1200 m) and at Perumal Peak
shola on the eastern slope. This species is under cultivation in the Sacred Heart College fernery
at Kodaikanal. It was omitted by Dixit (1984).

Distribution: Endemic to South India and Sri Lanka.
28. Microlepia platyphylla (Don) J.Sm.

A beautiful and rare species with large, elongated-triangluar, coarse segments and tall fronds
recorded by the author from two places in the Palnis: Perumal peak shola (1700 m) and
Vellagavi (1200 m).

Distribution: South India, Nepal, Sikhim, Bhutan, Sri Lanka, Myanaung (Burma).
29. Microlepia strigosa (Thunbg.) C. Presl

Occurs sporadically in the dense forests of the Tirunelveli Hills at 1500 m. A single plant
was seen on the stream-bank in Lamb’s Rock shola (1800 m) in the Nilgiris.

Distribution: N. & S. India, Nepal, Bhutan, Sri Lanka, the Malay Peninsula, and Islands,
Polynesia, China, Taiwan, the Philippines, Japan, Korea, Fiji.
30. Oleandra musifolia (B1.) C.Presl

In the Palnis it occurs gregariously and the author has found it almost entirely covering a
huge semi-exposed rock in Tiger shoia (1700 m.). In 1986 he recorded it from Idliar forest in
the Anamallays (1200 m) and more recently in Sheikal Mudi forest in the Anamallays at 1200
m. It was also collected from a rock on a stream-bank by the Naduvattom-Gudalur road in the
Nilgiris. This species prefers partially exposed habitats and may be on the increase since the
forest began being cleared.

Distribution: South India, Sri Lanka, extending to Java.
31. Ophioglossum reticulatum L.

The only record made by the author is from the edge of Berijam lake (2300 m) in the Palnis
where it was seen as a colony among Ptferidum reticulatum (B1.) Nakai, the common bracken of
India. It has been widely mis-reported as being O. vulgatum L., which does not occur in India.
A range of morphology occurs between the present species and O. petiolatum Hook., which is
usually treated as being merely a form of O. reticulatum
Distribution: India (Central India, Himalaya and S India); Nepal, Bhutan etc. pantropical.

32. Osmunda hugeliana C. Presl.

This species was seen as an extensive colony along the tributaries feeding into Kodaikanal
Reservoir (2300 m) although it is now totally eliminated there by the construction of a dam.
Another colony was seen on the Berijam-Munnar road in the Palnis and two further records have
been made in the Anamallays: Nirar dam and Periyakallar (1200 m). In all cases the habitats
are fully exposed. Often reported as O. regalis in error, this more delicate species has smaller,
shorter pinnules and narrower pinnae.

Distribution: S. India, ? S.E. Asia.
33. Cyrtomium caryotideum (Wall. ex Hook. & Grev.) C. Presl.

This species was collected from forests around Top Station in the Palnis (1800 m) in 1969
and later from Gundar shola on the high plateau of the Palnis. A single plant was also collected
from a shola on the Ootcamund-Avalanche road in the Nilgiris (2300 m).

Distribution: N. Pakistan, N. & S. India, Nepal, Bhutan, China, Taiwan, Vietnam, Japan.

FERNS OF THE WESTERN GHATS 9

Fraser-Jenkins (pers. comm. 1995) points out that he collected a distinct species with smaller,
less toothed or auriculate pinnae in the Shevaroy Hills, N.W. of Yercaud, in 1978. He recognises
_ this as C. micropterum (Kunze) Ching., a species near to C. divicola (Mak.) Tag. from Japan and
China; it occurs in S. India, E. Africa, Cameroon and Madagascar.

34. Pleopeltis macrocarpa (Bory ex Willd.) Kaulf.

A high-altitude epiphyte on the high plateau of the Palnis (2300 m). Also observed as an
epiphyte in a shola on the way to Terrace Estate in the Nilgiris.
Distribution: Endemic to South India and Sri Lanka.

35. Polystichum subinerme (Kunze) Fraser-Jenkins

The only locality by the present author is from the shola at the top of Agasthiamalai (1600
m) where it grows on partially shaded stream banks. Fraser-Jenkins (nos. 9037-9041, 9083,
9084, B.M.) found it commonly in the Shevaroy Hills, N.W. of Yercaud in 1978.

Distribution: Endemic to Southern India.
36. Pronephrium triphyllum (Sw.) Holttum

During the author’s survey of the Western Ghats, the only record made was from the Upper
Kothayar hills (1500 m) where it grows under trees and along stream-banks forming a colony.
Distribution: N. & S. India, Bangladesh, Sri Lanka, Myanaung (Burma), Thailand, China,
Taiwan, Japan, Malesia, Queensland (Australia), the Philippines.

37. Pteris geminata Agardh

This species is a large and beautiful fern which the author has seen growing in Kalakad
forest (1100 m) and in the forests between Sholayar Dam and Chalakudi in the Anamallays at
1200 m.

Distribution: Endemic to South India.
38. Pteris mertensioides Willd.

Only two localities for this elegant large species are known to the author: one from forest
between the Sholayar Dam and Chalakudi and the other from Nadugani forest in the Gudalur
range in the Nilgiris at 1200 m.

Distribution: S.India, Sri Lanka, Borneo, the Philippines, Society Islands.
39. Pteris multiaurita Ag.

A single record of this species was made by the author from the Karaiar-Kannikatty road in
a partially exposed site at 600m in the Tirunelveli Hills. In a remarkable research study, Walker
(1958) found that P. multiaurita is fully interfertile with the quite unrelated species, P.
quadriaurita Retz., from Sri Lanka and S. India, the fertile diploid sexual hybrids may be so
numerous as to dominate and crowd out the parents and have been named P. x otaria Bedd., with
intermediate frond morphology.

Distribution: Endemic to South India.
40. Pteris vittata L.

Collected in 1969 from an exposed stream bank at the foot of the northern slope of the
Palnis(400 m) and again from the fully exposed roadside at Upper Kothayar Dam.
Distribution: Ubiquitous throughout the tropics and subtropics of the old world, forming a semi-
cryptic cytological complex of diploids, tetraploids and triploid hybrids.

41. Schizaea digitata (L.) Swartz

The only record made by the author is from a deciduous forest at the tropical Botanical
Garden, Palode; Trivandrum, where it grows as a colony on the forest floor at 700 m.
Distribution: South India, the Malay Peninsula, Philippines, Australia, New Zealand, Polynesia,
the Mascarene Islands, tropical America, the West Indies.

42. Thelypteris confluens (Thunb.) Morton

Beddome recorded this species from Perumalmalai in the Palnis at 1600 m. The present

author collected it from the same locality in 1969, which is now completely overgrown with

10 FERN GAZETTE: VOLUME 15 PART | (1995)

Lantana. However, this species also grows among grasses and sedges at the periphery of
Berijam lake at 2300 m.
Distribution: South India, Thailand, Laos, Malesia, New Zealand, Africa.
43. Vittaria flexuosa Fée

Collected from a tree on the stream-bank of a shola on Mackay’s Path in the Anamallays
(2000 m) and again from Kolli hills at 1200 m. A very rare epiphytic species.
Distribution: N. & S. India, Sri Lanka, Nepal, Bhutan, Thailand.
44. V. microlepis Hieron.

This species was seen at the base of a large tree in the coffee-plantation in Manalur in the
Palnis, at 1100 m. A second record is from the Agasthiamalai forest (1200 m).
Distribution: Endemic to South India and Sri Lanka. Sledge (1982) reported it only from Sri
Lanka.

ACKNOWLEDGEMENTS
I express my sincere thanks to the Department of Science & Technology, Government of India
for financing the first project on the ferns of the Western Ghats. I am deeply grateful to the
Conservators of Forests of Kerala and Tamil Nadu for granting permission to collect ferns in the
Western Ghats. I also thank Mr A.C.Jermy. Natural History Museum, London for making
suggestions for improving the text and Mr C.R. Fraser-Jenkins for detailed and extensive
revision of the paper.

REFERENCES

BEDDOME, R.H. 1864. Ferns of Southern India. Gantz Bros, Madras [reprint 1970, Today &
Tomorrow’s Printers & Publishers, New Delhi].

DIXIT, R.D. 1984. A Census of the Indian Pteridophytes. Botanical Survey of India,
Department of Environment, Howrah.

FRASER-JENKINS, C.R. 1989. A monograph of Dryopteris (Pteridophyta: Dryopteridaceae)
in the India Subcontinent, Bull. Brit. Mus. Nat. Hist., Bot., 18(5): 323-477.

HOOKER, W.J. & BAKER, J.G. 1868. Synopsis Filicum [ed. 1].

KUNZE, G. 1851. Filices Nilagiricae, Linnaea 24: 239

MANICKAM, V.S.1986. Fern Flora of the Palni Hills (South India). Today & Tomorrow’s
Printers & Publishers, New Delhi.

MANICKAM, V.S. & IRUDAYARAJ. V. 1992. Pteridophyte Flora of the Western Ghats-South
India. B.1.Publications, New Delhi.

MORTON, C.V. 1967. Studies of Fern types, 1, Contrib. U.S. Nat. Heb. 38: 29-83.

NAIR, N.C. & DANIEL, P. 1986. The floristic diversity of the Western Ghats and its
conservation: A review. Proc.Indian Acad. Sci. Supplement, 127-163.

SLEDGE, W.A. 1956. The Ceylon species of Leptochilus, Ann.Mag. Nat. Hist. ser. 12, 9: 865-

Bie:

SLEDGE, W.A. 1962. The Athyrioid ferns of Ceylon, Bull. Brit. Mus. Nat. Hist. Bot, 2(11):
Di 323)

SLEDGE, W.A. 1968. The Hymenophyllaceae of Ceylon, J. Linn. Soc., Bot., 60(383): 289-
308.

SLEDGE, W.A. 1973. Native and Naturalised species of Adiantum in Ceylon, Ceylon J. Sci
(Bio. Sci). 10(2): 144-154.

SLEDGE, W.A. 1981. The Ceylon species of Osmunda, Kew, Bull. 36(1): 9-11.

SLEDGE, W.A. 1982. An annotated check-list of the Pteridophyta of Ceylon, Bot. J. Linn. Soc.
84: 1-30.

WALKER, T.G. 1958. Hybridisation in some species of Pteris L., Evolution 12: 82-92.

FERN GAZ. 15(1)1995 7

ON THE ECOLOGY AND POPULATION DYNAMICS OF A DUTCH
POPULATION OF POLYSTICHUM SETIFERUM
(DRYOPTERIDACEAE: PTERIDOPHYTA)

PIET BREMER
Roelingsbeek 1, 8033 BM Zwolle, The Netherlands

Key words: ecology, Noordoostpolder, Netherlands, Polystichum setiferum

ABSTRACT

The ecology and population dynamics of a population of Polystichum setiferum (Forssk.)
Woynar have been surveyed in the Kuinderbos. This area, situated in the Noordoostpolder,
reclaimed from the former Zuiderzee, harbours 95% of the Dutch population. These ferns
grow on calcareous sands on ditch banks under a canopy of Fraxinus excelsior L., Picea
sitchensis (Bong.) Carriére or Fagus sylvatica L. The ecology of the species changed during
15 years in view of exposure and composition of the canopy. At other sites in the
Ijsselmeerpolders, i.e. the areas reclaimed from the Zuiderzee, the species thrives on ditch
banks on clayey soils under deciduous species.

Individuals were mapped and monitored for 15 years. There was an increase in
population, although severe winters reduced survival and growth. The Kuinderbos
population has a high recruitment compared to other populations in the Atlantic region.
Young plants appeared in the spore shadow of adult plants. Polystichum setiferum is able to
colonize newly planted woods between 10 - 15 years after planting.

INTRODUCTION

Polystichum setiferum has only recently become known in the Netherlands. In 1956 material,
named as Polystichum aculeatum (L.)Roth., was collected in the Savelsbos (Limburg), in the
most southern part of the Netherlands. In 1979 the material was revised and correctly identified
(Heukels & de Graaf 1979). In the same year the species was found in the Kuinderbos, one of
the woods laid out in the Noordoostpolder. The Kuinderbos is considered to be the richest area
for ferns in the Netherlands. After 1979 the total number of fern taxa known from this locality
increased to 27, with first records of various taxa (Bremer 1980, 1988). Since 1978, populations
of rare species have been monitored; some of them annually, others less frequently (Bremer
1994).

The question is under which ecological circumstances Polystichum setiferum is able to
grow in the Kuinderbos. A monitoring programme was started at the Kuinderbos to ascertain the
development of this and other rare species. Since many fern species are growing here under - by
Dutch standards - unique circumstances we wondered if these populations would be able to
maintain themselves and we were also interested in the factors influencing the size of the
population. Moreover, we wanted to reconstruct the process of colonization.

THE STUDY AREA

In 1932 the Zuiderzee was closed, and since then four polders were reclaimed:
Wieringmeerpolder (1933), Noordoostpolder (1942), Oostelijk Flevoland (1958) and Zuidelijk
Flevoland (1969). In these polders over 15,000 Ha of woods were planted. These woods were
planted on poor soils in the oldest polders but in both Flevoland polders they were laid out
especially on clayey soils. Various tree species were planted, especially Pinus nigra, Picea
abies, Populus x canadensis, Quercus robur, Fraxinus excelsior, Fagus sylvatica and Acer
pseudoplatanus, depending on substrate, drainage and the forestry management philosophy at
the time.

The Kuinderbos differs from all the other woods in having a “peat erosion area’, where peat
has been partially eroded, and the potholes were filled in with fine-grained sand. Ditches were

12 FERN GAZETTE: VOLUME 15 PART | (1995)

dug with a density of up to 0.7 km per Ha. Their depth ranges from 0.3 to 1.6 metres. The phreatic
level is usually below the bottom of these ditches. On ditch banks the fine-grained, calcareous
sand is exposed (figure |). The ferns of all woods were surveyed between 1979 and 1994.

Figure 2.
| Distribution of Polystichum setiferum in the
= e, Netherlands (1979 - 1993).

Fe Psi

Figure 1. The ditch bank habitat of Polystichum setiferum (Ps) and other rare ferns (As =
Asplenium scolopendrium, Gd = Gymnocarpium dryopteris) in the Kuinderbos (The
Netherlands). Psi = Picea sitchensis, Fe = Fraxinus excelsior, fgs = fine grained sand, sp =
sphagnum peat, pl.s = pleistocene sand, w.l = phreatic level (winter), s.1 = phreatic level
(summer).

METHODS

From 1979 onwards all ferns in the Kuinderbos were mapped. The number of fronds per plant
(n), the number of fertile fronds per plant (ng) and the maximal size of fronds per plant (Lyyax)
were measured annually in two plots at the end of the summer. The whole Kuinderbos
population was surveyed in this way in 1979, 1984, 1990 and 1993. In 1979 and 1993 the habitat
was described in terms of substrate, canopy composition, depth of ditches, exposure and
inclination. Twelve populations were examined in the UK and Belgium in terms of population
structure (n, nf, Lyyax) and habitat. This information had to be used as a reference in view of the
limited age of the Dutch populations.

ECOLOGY OF POLYSTICHUM SETIFERUM
In the Kuinderbos the ferns are linked with ditch banks in the “peat erosion area” (X°=158.9 p<
0.001). They grow on a topsoil of fine calcareous sand overlying peat. Fagus sylvatica and
Picea sitchensis dominated the canopy in 1979, Fraxinus excelsior being more important in
1993 (X°=35.8 , p< 0.001). The ferns are growing in moderately deep ditches (0.5 - | m deep).
In shallow ditches (< 0.5 m) the layer of fine sand is too thin for successful establishment. In
1993, the ditches in which ferns were established were shallower on average than in 1979 (t =
4.6, p<0.05). The ferns are growing over the whole range of the ditch banks. The ferns growing

ECOLOGY OF POLYSTICHUM SETIFERUM 13

on the lower part of the banks are apparently able to survive a short period with a high phreatic
level. There was no difference in relative height between 1979 and 1993 (t = 0.6, n.s). In 1979
- the plants preferred a NE exposure (X°=28.4, p <0.001); no preference was observed in 1993
(X*=3.1, n.s) (table 1).

Kuinderbos 1979 1993
f=59 n=128
substrate fine sand ait 56 128
podzol 27 - -
peat 20 - -
clay 8 3 -
other 14 - -
X"=158.9 X°=284.7
p < 0.001 p < 0.001
canopy Fagus <| 44 36
compostion Fraxinus 19 8 ay
P. sitch. i i! 34
P. abies 25 - l
Quercus 28 - -
Acer ps. 5 - =
other 14 - -
G3=336.6 G3=184.6
p < 0.001 p < 0.001
depth of ditches (cm) 88.2+16.2 JR 5=20:0
(min. - max.) 50-160 30-130
t=4.6
p < 0.05
relative height 0.46+0.16 0.46+0.25
(min. - max.) 0.11-0.88 0-1.0
t=0.6 n.s
exposure NE 50 50 He
SW 50 9 54
X°=28.4 m= 331
p<0.001 n.s

Table 1

The ecology of Polystichum setiferum in the Kuinderbos, the Netherlands, as ascertained in
1979 and 1993. The first column gives the percentages for the Kuinderbos for substrate, canopy
and exposure of ditch banks. relative height = distance from ditch bottom to plant/ depth of ditch.

14 FERN GAZETTE: VOLUME 15 PART | (1995)

Since 1979 Polystichum setiferum has been found on reclaimed soil in five other planted
woods in the province of Flevoland as well (figure 2). The number of individuals ranged from
| - 2 per wood. These were growing on boulder clay (1), sandy clay (2) (Smit 1989), clay (3)
and medium fine sand (1), always of a calcareous nature. The canopy consisted of deciduous
trees, especially Fraxinus excelsior and Populus x canadensis. The plants were linked with ditch
banks, except for one plant on boulder clay.

Elsewhere in the Netherlands solitary plants of this species have been found on a wall at Den
Haag and at a well near the Bunderbos in Z.-Limburg (van der Meijden & Holverda 1991,
pers.comm. A.Koster) (Figure 2).

POPULATION STRUCTURE AND POPULATION DYNAMICS

Kuinderbos
The population in the Kuinderbos varied from 59 plants in 1979 to 128 plants in 1993,

representing 95% of the current Dutch population. Of the 1979 population, only 10% was still
alive in 1993 (figure 3a). The maximum size of fronds increased after 1987 (figure 3b). Of the
1979 population 75% of the plants were concentrated at one site of ca. 3m° (plot 1), the other
plants growing solitary at scattered sites. There were only 8 adult plants. The population was at
a mininum in 1987 (18 plants), but increased from 1989/90 onwards. In 1993 87% of the plants
were growing at five sites in the spore shadow of an adult plant (figure 4). One of these sites
was monitored annually (plot 2, figure 5). Since 1979 the percentage of adult plants increased
(34.4%, table 2).

number of plants

120

100

0 At a Ee oo) eee

maximum length of fronds

0
1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 19921993
years

Figure 3.

a. —.— the number of plants in the surveyed Kuinderbos during 15 years.
—+— the number of plants from the 1979 cohort

b. The maximum size of fronds, all fronds taken into account.

ECOLOGY OF POLYSTICHUM SETIFERUM

5 number of plants

Figure 4.

The distance effect between recruitment and solitary adult (fertile) plants.

npop

n
ants
range
anf+s
range
Jont
fn
almax
range
%j
sub.j

Table 2

Kbos 1979
5

61
4.443.7
1-19
0.85 + 2.1
0-9

9.8 +41.5.
11.8

23.5 = 20:5
2-83
26.8

20

2

Kbos 1993
8

128

6.3 + 4.9

2 - 40
1844.2

0 - 28

S26 255
34.4

[8.5 4 32.2
4-119
13.3

38

4

Dev/Wales
6

395

18+ 6.2

1 - 45

a

0 - 40

54.8 + 42.5
68.6

66.5 + 28.1
2 122

a3

67

Some characters of the populations surveyed.
npop = number of (sub)populations surveyed, Kbos = Kuinderbos, Dev/Wales = populations in

Devonshire/Wales (see appendix). n = number of plants surveyed, an
fronds per plant, anf = average number of fertile fronds per plant, %onf = average percentage of
fertile fronds per plant, fn = percentage of fertile plants, aL;yqgx = average maximum length of

&

distance from fertile plant (m)

N.Ireland
5

176
6.38:472
1-51

3.7 + 6.4
0 - 40
35.0 + 44.4
41.5
49.7+ 41.2
1 - 136
PIR:

80

Belgium
l

54

7.2 + 6.4
3232

5.4 + 6.3

0 - 28
Oka
iss

72.8 + 27.4
6 - 110

1.8

100

average number of

fronds per plant (in cm), %j = percentage of juvenile plants (Lmax < 8 cm), sub.j = percentage
of (sub)population with recruitment.

16 FERN GAZETTE: VOLUME 15 PART | (1995)

At plot | (in deep shadow cast by Fagus sylvatica and Picea sitchensis) the number of plants
decreased since 1978 and even disappeared after 1988. The average of Lmax increased to 34 cm
(4.3 cm per year); no plants reached the adult stage. At plot 2 (lightly shaded by Fraxinus
excelsior) recruitment took place in the spore shadow of an adult plant from 1989 onwards.
Within four years 61% of the plants reached the adult stage. The average of Lmgx increased with
13.1 cm per year.

number of plants max.length of fronds (cm)
aN
N
40 ‘Ni 40
NS
N
N
- S
: SS US
Z p SN NS
Z Z VN
p Z Z NaS
Ae Z N AJ
Zias Z N §
Zunes Z NSN B§
A Zune A N &
Zunes Z Z N S
mam & &B Z N NS
20 ee eee Ze Z Zh abet WN NN 20
Bl Zl ZZ Z N SN &
Z| |Z iZ) iZ| 2 Z N 8 B®
Z Zins a ef Z S S&S S
Z A Z Z Z Z \ SX NS
Bn Be B&B B eZ Z N WN &
ZAI |Z) |Z) |Z) l2) 2 A NWN RR
- gZ Z Z Z ZB Zz Z X NS SS
gZ Zz Zz Z Zz Z Z Z S N N
10 a eee oo Zo a Zee eee BA on eens \~ a SH SS
Zz iZ| (2. Z| 2 IZ 12 Z No SN 70
Z Z Z Z Z Z Z Z Rony SS NY NS
Z Z Z Z Zz Z A Z S&S SS SS S
E Zi SNe cee ces Z SN S BS AR
ZZ 2 2 SZ Zl Zi) 2 A NSN SN BW
Z Zz Z Z cB Zi Z Z Z SWS SX SS SX
Amie &@ & 4 4 Z NS WN BR
A AoA A Be ee eh SNS SN 8) 4

@) A = S .
1978 1980 1982 1984 1986 1988 1990 1992 1994
time

Figure 5.

The number of plants and the average maximum size of fronds (aLmax) for two (cohort)
populations during 17 years.

.___. number of plants 1978 cohort (Plot 1) *—* number of plants 1990 cohort (Plot 2)

aLmax 1990 cohort (Plot 2)

WOH
SS

ZZ aLmax 1978 cohort (Plot 1)

Other populations

The average number of fronds per plant (an) does not differ much between the Kuinderbos
population (1993) and the UK/Belgium populations. The average of Lmax 1s much lower in the
Kuinderbos population (1979/1993) as in the other populations. The correlations between n and
Lmax are always significant, the Kuinderbos (1993) having nearly the same correlation
coefficient as the other populations (table 3). At the Kuinderbos (1979) the percentage of
juvenile plants was higher than in other UK populations, except for those of Northern Ireland.
A concentration of juvenile specimens was observed in some (sub)populations due to
regeneration in the spore shadow of adult plants, but in other (sub)populations there was no
recruitment. Therefore the percentage of populations showing recruitment was lower in the
Kuinderbos than in the other populations examined.

ECOLOGY OF POLYSTICHUM SETIFERUM 17

ie Jong Lmax

I = is 0.70
n Z 0.76 0.43 0.49

3 0.84 0.33 O52

+ 0.87 0.46 0.54
nf l = Bs

2 0.79 0.65

3 0.68 0.65

= O75 0.69
Yon l As

Z 0.76

5 0.69

+ 0.81

Table 3

Correlations between some parameters for the Kuinderbos-population in 1979 (1) and in 1993
(2) and populations of Polystichum setiferum in Devonshire/Wye valley (3) and in Northern
Ireland (4) (see appendix).

n = number of fronds per plant, nf = number of fertile fronds per plant,

%ont = percentage fertile plants, Lyyax = maximum length of frond per plant, — = no correlation
calculated due to skewness of values. All the correlations are significant (p < 0.01).

FERTILITY
The average number of fertile fronds per plant (ang) increased from 0.8 in 1979 to 1.8 in 1993

and is lower than in other examined populations. The percentage of fertile plants increased over
15 years, but is still lower than that found in UK populations. The average percentage of fertile
fronds increased over the same period and equalled that of the populations examined in
Northern Ireland (table 2). A relation exists between fertility and the length of the fronds. At the
Kuinderbos plants with Lyyax of at least 0.7 m were fertile, except for 1979 when few adult
plants were growing in the area. Individuals with Lmax < 0.3 m can be fertile. In the populations
examined in the UK, plants with Lpax < 0.3 m were always found to be sterile and it was
observed that taller plants (Lyax > 0.7 m) can be sterile as well (figure 6).

DISCUSSION
Ecology: Polystichum setiferum is a very rare species in the Netherlands. Living specimens
have established in the woods recently laid out in the Noordoostpolder and Oostelijk Flevoland.
They are correlated with ditches, calcareous substrates and canopies of various tree species.
There was a shift in ecology of the Kuinderbos populations over 15 years with respect to
exposure and canopy composition as currently more plants are growing under specimens of
Fraxinus excelsior. There is more incoming light under Fraxinus excelsior.

In the UK the species mainly occurs in deciduous woodland in river valleys, along the
streambanks, on lanebanks and in hedgerows (Page 1982). It prefers sloping, permanently
slightly moist soil with a pH between 6.5 - 8.0. The Kuinderbos populations fulfil the
requirements of slope, pH and moisture since the subsoil of peat supplies the upper layer of fine-
grained sand with capillary water (figure 1). Its habitat differs in having Picea sitchensis in the
canopy. The species is indicated by Dostdl & Reichstein (1984) to be acidiophilous, but several

18 FERN GAZETTE: VOLUME 15 PART | (1995)

is)
(=)

—t
ee
je)

sy
Oo
i=)

oo
o

percentage fertile plants

) —— =
0 20 40 60 80 100 120 140 160

maximum length (classes)
Figure 6
a. The percentage of fertile plants in relation to classes based on the maximum size of fronds per
plant for the Kuinderbos population
IDS (aS S58). = 1984 (n = 32), —*— = 1990 (n = 42), —-[]— = 1993 (n = 128)
b. The percentage of fertile plants in relation to classes based on the maximum length of frond
per plant.
= = populations in N.-Ireland
—-+—- = populations in South Devonshire/Wye valley (England/Wales)

species which are calcicole at the border of their range and not calcicole in the centre are known
(Hengeveld 1990). This can even be noted within the UK for Polystichum setiferum (Page
1982). Because thousands of Ha of woods have been laid out on clay in Flevoland, the district
comprising the polders reclaimed from the Zuiderzee, new sites with Polystichum setiferum are
to be expected.

Population Structure and Dynamics: In 1979 the Kuinderbos population was young, with
only 8 adult plants. We tried to establish when first colonization had taken place. Under heavy
shade (plot 1) the average Lyyax increased with 4.3 cm per year, under light shade (plot 2) with
13.1 cm per year. Considering the tallest plant in 1979 (83 cm) this plant may have been
between 7 and 19 years old; therefore establishment apparently took place between ca. 10 and
22 years after planting in 1949 - 1951. In Oostelijk Flevoland (Overijsselse Hout) the first
individual was established 10 - 15 years after planting (Smit 1989). Although adult plants have
a high spore production the recruitment level in the Netherlands is low. Most recruitment takes
place in the spore shadow, within 5 m from an adult plant. A high density of spores seems to be
necessary for establishment. Established plants suffer from severe winters. In plot 1 36 % of the
plants died in the severe winter of 1978/79. After 1980 the number of plants declined to a low
level in 1987, negatively influenced by the severe winters of 1984 through 1987, which caused
damage to fronds and probably interfered with recruitment. In the Kuinderbos Polystichum
setiferum is at the northern limit of its mainland European range (Jalas & Suominen 1972), its

ECOLOGY OF POLYSTICHUM SETIFERUM 19

range coinciding with January isotherm of 0°C. It does not imply that Polystichum setiferum can
not tolerate low temperatures for some time, because plants survived temperatures of -23°C in
~ ditches during the winter of 1978/79. Nevertheless in the Netherlands severe winters are found
to cause a lot of frost damage (necrosis) to various fern species, for example Asplenium
scolopendrium.

In the Kuinderbos the plants are smaller than in UK populations due to their more recent
establishment. The average number of fronds per plant is nearly the same, even in population
with little recruitment, indicating that growth is mainly expressed in the size of the fronds. As
Page (1982) stated recruitment in populations in the UK takes place rapidly, often on damp
banks where these are exposed by erosion, as was confirmed in this study. In the Kuinderbos
many km of ditch bank seem appropiate for calcicolous species as Polystichum setiferum due to
erosion. On one hand erosion of ditch banks can be a reason for a low chance of establishment
and at plot | erosion was one of the reasons for the death of plants. On the other hand erosion
produces new microhabitats, which are suitable for establishment. Unlike Polystichum
setiferum, Asplenium scolopendrium had a high recruitment in the Kuinderbos during the last
15 years, establishing itself in microhabitats created by erosion.

Fertility: Fertility can be supressed under heavy shade, as indicated for plot 1. In the
Kuinderbos the fertility of Asp/enium scolopendrium could be shown to be diminished by frost
damage. Fertile individuals may become sterile after a severe winter. This may have played a
role at plot | as well. In the UK a high percentage of larger plants can be sterile, while at the
Kuinderbos these are always fertile. Probably there is more competition in the UK, since there
the species can form stands with up to 4 - 6 adult plants per m* with no plants in between due
to accumulation of died fronds. Up to 1993 such stands have not been formed in the Kuinderbos.

APPENDIX
The surveyed populations in the UK and Belgium.
United Kingdom
Northern Ireland (July 1993)
-Helen’s bay (Crawfordsburn), 5°43’ W 54°39’ N; lane bank under Acer pseudoplatanus.
-Crawfordsburn Park, 5°43’ W 54°39’ N; along rivulet in deciduous woodland.
-Crawfordsburn Park, railway bridge, 54°3’ W 54°39’ N; Acer pseudoplatanus-Fraxinus
excelsior-Tilia woodland.
-Carnalea (Bangor), 5°42’ W 54°41’ N; Alnus glutinosa - Acer pseudoplatanus woodland
along rivulet.
-Holywood, Redburn County Park, 6°50’ W 54°38’ N; mixed deciduous woodland on slope.
Devonshire (July 1994)
-Redbrook, 2°40’ W 51°48’ N; Tilia - Ulmus woodland.
-Tavistock Woodland Estate, 3°40’ W 50°17’ N; Castanea sativa - Acer pseudoplatanus
woodland in reserve.
-Slapton Wood, 3°39’ W 50°18’ N, Acer pseudoplatanus woodland in reserve.
-Slapton, 3°39’ W 50°18’ N; hegdebank between Slapton and Slapton wood.
-Avon, 3°7’ W 50°22’ N; Acer pseudoplatanus - Fraxinus woodland along river.
Wales (July 1994)
-Wye valley, Llandago, 2°42’ W 51°43’ N; Acer pseudoplatanus woodland.
-Wye valley, Llandago, Gleddon Shoots, 2°42’ W 51°43’ N; Acer pseudoplatanus-Fraxinus
excelsior-Tilia woodland.
Belgium (July 1987)
Ardennen, Comblain au Pont, 5°65’ E 50°45’ N; Acer pseudoplatanus-Fraxinus excelsior-Tilia
woodland along Ambléve.

20 FERN GAZETTE: VOLUME 15 PART 1 (1995)

ACKNOWLEDGMENT
I am grateful to Willem Hurkmans who critically reviewed the manuscript.

REFERENCES

BREMER, P., 1980. The ferns (Pteridophyta) of the Kuinderbos (The Netherlands), the
establishment of 23 species in a planted forest. Acta Botanica Neerlandica 29 (5/6): 351
- 357.

BREMER, P., 1988. Veranderingen in de varenflora van het Kuinderbos in tien jaar. De Levende
Natuur 89(3): 74 - 80.

BREMER, P., 1994. On the ecology and population dynamics of a Dutch sporophyte population
of Gymnocarpium dryopteris. The Fern Gazette, 14(8): 289-298.

DOSTAL, J. & Reichstein. S.T. 1984, Polystichum. In: Hegi G. (ed.) ///ustrierte Flora von
Mitteleuropa. Band I, teil 1 (Pteridophyta). Berlin, Hamburg. 3e ed.

HENGEVELD, R., 1990. Dynamic biogeography. Cambridge.

HEUKELS, P., & D.T. DE GRAAF. 1979. Over Polystichum aculeatum (L.) Roth en zijn
voorkomen in Nederland. Natuurhistorisch Maandblad. 68(4): 55 - 62.

JALAS, J & SUOMINEN, J., 1972. Atlas Flora Europaea. Pteridophyta.

MEIJDEN, R. VAN DER & HOLVERDA, W.J., 1991. Nieuwe vondsten van zeldzame planten
in 1988, 1989 en 1990. Gorteria 16: 125 - 147.

PAGE, C.N., 1982. The Ferns of Britain and Ireland. Cambridge.

SMIT, A., 1989. De naaldvarens (Polystichum-soorten) van het Overijssels Hout bij Lelystad.
Gorteria 15: 90 - 94.

FERN GAZ. 15(1)1995 21

THE ECOLOGY AND CYTOLOGY OF BRAINEA
INSIGNIS (BLECHNACEAE: PTERIDOPHYTA)

A. AZIZ BIDIN
Botany Department, Faculty of Life Sciences
Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia.

Key words: Brainea insignis, Malaysia, cytology, ecology

ABSTRACT

A chromosome count of n = 35 is recorded for the Malaysian cytotype of the monotypic
genus Brainea thus providing further information on the cytological position of the genus in
particular and the family (Blechnaceae) in general.

INTRODUCTION

Holttum (1966) grouped Brainea (Hk.) J. Smith together with Blechnum L. and Woodwardia J.
Smith under the Sub-family Blechnoideae of the Dennstaedtiaceae in his treatment of the
Peninsular Malaysia blechnoid ferns. Among the common principal characters of the sub-
family are: rhizome short, stout, erect or nearly so; fronds simply pinnate with unlobed or
rarely lobed pinnae, sterile and fertile pinnae of same shape or the fertile pinnae very narrow;
veins free except for a series of narrow costal areoles in Woodwardia and in fertile fronds of
Blechnum indicum; sori close to the midrib, linear, each protected by an indusium along its
outer side, in Brainea without indusium. However other authors mostly raised the sub-family
rank of all blechnoid ferns into the family level - Blechnaceae - on the ground of (among other
characters) having the unfolding leaves tinged with red due to the presence of 3-
deoxyanthocyanins.

Tryon and Tryon (1982) mentioned nine genera and c. 175 species for Blechnaceae of which
three are Tropical American (Woodwardia, Blechnum and Salpichlaena). Among the genera
shared with the Old World are Blechnum and Woodwardia. Other genera confined to the Old
World but which are absent in Malaysia are Doodia R.Br., Pteridoblechnum Hennipm. and
Sadleria Kaulf. Most of the authors including Tryon and Tryon (1982) and Lovis (1977) placed
Stenochlaena under Blechnaceae, whilst Holttum (1966) grouped it together with Preridium,
Histiopteris, Pteris and Acrostichum under Sub-family Pteridioideae of Dennstaedtiaceae.

Lovis (1977) listed eight genera under the fern family Blechnaceae omitting Diploblechnum
Hayata. These are Blechnum, Salpichlaena, Doodia, Brainea, Sadleria, Woodwardia (incl.
Lorinseria), Pteridoblechnum and Stenochlaena. The chromosome base numbers for these
genera ranged from 28 to 40 with Blechnum showing an extensive aneuploid series in a
sequence from 28 to 36, ie. 28, 29, 31, 32, 34, 36 (and c.37).

DISTRIBUTION AND ECOLOGY

Brainea is a monotypic genus, comprising the single species, Brainea insignis (Hk.) J.Sm.
Holttum (1966) noted that this sole species is distributed from the Khasya hills eastwards to
Southern China and southwards to Tenasserim, Siam, Malaya and Northern Sumatra. He further
noted that the species could only be found in three locations in Peninsular Malaysia, ie. on the
summit of Gunung Terbakar, Cameron Highlands, on rocky headlands of Tanjung Selantai,
Johor and in Pulau Sembilan, Perak. Gunung Terbakar referred to by Holttum might have been
one of the summits found in the Cameron Highlands area of the Main Range, while Pulau
Sembilan are the numerous islets around Pulau Pangkor; the main island being not far from the
coast of Perak State, west of Peninsular Malaysia.

a) FERN GAZETTE: VOLUME 15 PART | (1995)

Figure 1. Brainea insignis on the seaside headland of Tanjung Selantai Johor.

Figure 2. Brainea insignis grown at the UKM Fern Garden.

BRAINEA INSIGNIS:ECOLOGY AND CYTOLOGY 23

Figure 3. Meiosis in Brainea insignis showing 35 bivalents, x1000. Acetocarmine squash

preparation. Plant collected from the only known locality in Malaysia, Tanjung Selantai Johor,
and grown in Universiti Kebangsaan Malaysia Fern Garden, Bangi.

Figure 4. Explanatory diagram of figure 3 showing 35 chromosome pairs in a diploid
specimen.

24 FERN GAZETTE: VOLUME 15 PART | (1995)

Past records kept at the local herbaria in Malaysia, and also botanical studies carried out
extensively by the author in these areas revealed that the species is only found in a small
population in Tanjung Selantai, Johor, on the southeastern coast of Peninsular Malaysia. From
a population of about 50 plants observed in 1985 the number has dwindled down to less than 10
plants, due mainly to casual clearance of the vegetation on the headland. Figure 1 shows. the
locality on the rocky headland of Tanjung Selantai where the species was observed by the author
in 1985. Several plants had been collected in 1988 and brought back to the Universiti
Kebangsaan Malaysia (UKM) Fern Garden in Bangi for conservation purpose and the species
had adapted well (Figure 2).

CYTOLOGY

Cytologically the fern family Blechnaceae shows a wide range of basic chromosome numbers
with 28 being the lowest number found in Blechnum whilst the highest is 40 found in the
Tropical American genus, Salpichlaena. Blechnum shows an array of basic chromosome
numbers in an almost unbroken sequence from 28 to 36. Walker (1973) postulated the primitive
number in Blechnum could be 33 as found in Brainea and Sadleria. Thus, substantial aneuploid
changes occur in the genus. Lovis (1977) also noted Brainea with the base number of 33 and
Woodwardia with two base numbers, te. 34 and 35.

Fixations were made on Brainea insignis grown at the UKM Fern Garden and gave
excellent meiotic preparations, one of which 1s illustrated in Figs. 3 & 4 and showing n = 35
with clarity. Thus, the present study reveals the existence of two base numbers for the
monotypic genus Brainea, ie. 33 (from established earlier records) and 35 through this
investigation.

The locality and morphological attributes for the cytotype (n=33) listed by Lovis (1977) is
not known. It is evident that here at least two different cytotypes exist in B. insignis so far. It
should be pointed out that a better and clearer picture would emerge if more cytotypes from
other geographical areas such as Thailand, Southern China and Sumatra become known.

ACKNOWLEDGEMENTS
The author wishes to thank Mrs Rusea Go for assistance in the laboratory and Dr. T. G. Walker
of Newcastle-upon-Tyne, U.K. for reviewing the manuscript. This work is supported by the
IRPA Grant No. 04-07-03-007 to which the author is indebted.

REFERENCES
HOLTTUM, R.E. 1966. Flora of Malaya IT. Ferns. Govt. Printing Office, Singapore.
LOVIS, J.D. 1977. Evolutionary Patterns and Processes in Ferns. Adv. Bot. Res. 4: 229-415.
TRYON, R.M. & A.F. Tryon. 1982. Ferns and Allied Plants with Special Reference to Tropical
America. Springer Verlag, New York, Heidelberg & Berlin.
WALKER, T.G. 1973. Evidence from cytology in the classification of ferns. In: JERMY, A.C.,
CRABBE, J.A. and THOMAS, B.A. (Eds.). The Phylogeny and Classification of the
Ferns Bot. J. Linn. Soc. 67. Suppl. 1: 91-110.

FERN GAZ. 15(1)1995 25

PROGENY STUDIES OF THE FERN HYBRID
POLYSTICHUM x BICKNELLI (DRYOPTERIDACEAE:
PTERIDOPHYTA)

I. PINTER
Edtvés Lorand University, Department of Genetics, Budapest H-1088,
Muzeum krt. 4/A, Hungary

Key words: Polystichum bicknellii, hybridization, allopolyploidy, meiosis.

ABSTRACT
Polystichum x bicknellii (Christ) Hahne is a triploid interspecific hybrid of the diploid P.

setiferum (Forsskal) Woynar and the allotetraploid P. aculeatum (L.) Roth. A detailed study
is presented of the meiotic division and spore formation of this hybrid. Meiosis is highly
irregular and a maximum 2-3% of the spores can germinate, and only a fraction of these
develops further.

From approximately 3.7 million spores 155 sporelings were raised, but almost 50% of
them were unable to survive. The sporophytes raised are very different morphologically.
Sixty-three of the 84 surviving sporophytes were checked cytologically and of these 59
proved to be hexaploid (2n=246) and four to be triploid (2n=123). The hexaploid plants
showed almost normal meiosis with some univalents and multivalents, while meiosis in the
triploid progeny was a completely disturbed process.

It is assumed that similar processes could also happen in nature, resulting in sexual
hexaploid and perhaps triploid apogamous species.

INTRODUCTION

Interspecific plant hybridization usually results in sterile Fl plants. The sterility is often
chromosomal, a consequence of disturbed meiosis and failure of pairing due to the partial or
total absence of synapsis between homologous chromosomes. This type of sterility can be
overcome by polyploidy. In ferns many such cases has been reported both in nature and the
laboratory (For example : Asplenium lepidum C. Presl, Brownsey 1976a; A. creticum and A.
haussknechtii Godet & Reuter, Brownsey 1976b; A. x lessinense, Rasbach et al. 1979; A.
adulterinum Milde, Lovis & Reichstein 1968; Phyllitis hybrida (Milde) C.Chr., Vida 1963,
1965; 1973; Cheilanthes fragrans (L. fil.) Swartz, Vida et al. 1983; Polystichum aculeatum,
Sleep 1966). The fern genus Polystichum contains four species in Europe. The base number is
x = 41 (Manton 1950), and this has been confirmed by further chromosome counts (Mitui 1975,
Daigobo 1972, 1973, 1974, Mehra 1961, Ghatak 1963, Love & Love 1961, Love & Solbrig
1964, Taylor & Lang 1963, Wagner 1973).

The genomic relationship of the four European species appears to be as follows:

Two morphologically and ecologically distinct diploid species, the simply pinnate alpine-
montane P. lonchitis (L.) Roth and the 2- to 3-pinnate Atlantic-Mediterranean P. setiferum
(Forsskal) Woynar, have given rise to the allotetraploid P. aculeatum with more or less
intermediate habitat and pinnation. The fourth European species P. braunii (Spenner) Fée is also
tetraploid with uncertain origin and genomic composition (Manton 1950, Meyer 1960, Manton
& Reichstein 1961, Sleep & Reichstein 1967, Vida 1966, 1972). Sleep (1966) made several
attempts to resynthesize P. aculeatum from the diploid hybrid of P. lonchitis and P. setiferum.
However the morphology was not in complete agreement with the expectations (see also Vida
& Pintér 1981).

Triploid hybrids between the allotetraploid P. aculeatum and both of its suspected diploid
progenitors have often been found in nature, where the species come into contact. The name P.
x illyricum (Borbas) Hahne was given to the combination of P. aculeatum and P. lonchitis, while
P. x bicknellii (Christ) Hahne refers to the cross between P. aculeatum and P. setiferum. In both

26 FERN GAZETTE: VOLUME 15 PART | (1995)

cases roughly 41 pairs and 41 univalents have been observed at meiosis, in accordance with the
allopolyploid origin of P. aculeatum (Manton 1950). The bivalents are formed between
chromosomes of the diploid species and one of the genomes of the tetraploid. Using the
genomic symbol “L” for one genome of P. lonchitis and “S” for P. setiferum, the three European
species (disregarding P. braunii) and their hybrids can be designated as follows:

P. lonchitis LL diploid species P. x lonchitiforme LS diploid hybrid
P. setiferum SS diploid species P. x illyricum LLS triploid hybrid
P. aculeatum LLSS allotetraploid species P. x bicknellii LSS triploid hybrid

The fertility of P. x i/lyricum was studied by Vida and Reichstein (1975). In spite of the
highly irregular meiotic division of this hybrid, some viable spores were found. Fifteen F2
progeny were cytologically tested. Most of them proved to be hexaploid or triploid. A single
diploid and a tetraploid were found also, but their origin by contamination could not be
excluded.

A similar but statistically more reliable investigation has been carried out with P. x
bicknellii, the other triploid hybrid. We wanted to study the fertility and its role in possible
interspecific introgression between P. setiferum and P. aculeatum.

Name Locality Collector
P. setiferum Villanyi Hills I. Pintér
near Bisse

LAT:45°40’N, LONG: 18°15’E
200 m. above S.L.
P. setiferum Bakony Hills, Tot valley I. Pintér
near Fenyof6
LAT:47°28’N, LONG:17°45’E
260m above S.L.
P. setiferum Mecsek Hills I. Pintér
near Orfii
LAT:46°05’N, LONG: 18° 10’E
220m above S.L.
P. lonchitis Gerecse Hills G. Vida
“Ebgondolta” forest, near Tata
LAT:47°40/N, LONG:18°15’E
150m above S.L.

P. x lonchitiforme Gerecse Hills G. Vida
“Ebgondolta” forest, near Tata
P. aculeatum Vértes Hills I. Pintér

“Maria” ditch near Szar
LAT:47°30’N, LONG: 18°30’E
200m above S.L.
P. aculeatum Biikk Hills I. Pintér
“Vadasz” valley near Omassa
LAT:48°07’N, LONG:20°37’E
700m above S.L.

P. x bicknellii Mecsek Hills G. Vida
@ Pole lay) “Szuado” valley near Orfii

P. x bicknellii Bakony Hills

Pos, 207) Tot valley near Fenyofo

Table 1. Sources of the fern specimens

POLYSTICHUM x BICKNELLII PROGENY 27

MATERIALS AND METHODS
The ferns used for the examinations were collected in their natural habitat (Table 1) and
maintained under greenhouse conditions. Spores were collected from the hybrids in the
greenhouse. Great care was taken to avoid spore contamination. A young frond was first isolated
by pulling it into a cellophane envelope before sporulation began. Later ripe spores were
collected and sown in Petri dishes on KNOP medium solidified by 1% agar-agar, and kept in
natural light at room temperature.

Mature prothalli covered with antheridia and archegonia were then selected and submerged
into distilled water for about three hours (intergametophytic selfing). After fertilisation was
accomplished the material was placed on agar. As soon as the developing sporophytes reached
a manageable size (2-3cm) they were transferred to soil.

For chromosome counts the root tips were treated with colchicine solution (0.2%), then
fixed in a mixture of abs. ethanol : glacial acetic acid 3:1 v/v. Excised roots (lcm) were washed
in distilled water, then digested in a solution containing 4% pectinase and 4% hemicellulase for
five hours in 37°C . Then the tips of softened roots were rinsed, stained in acetocarmine, and
finally squashed according to Manton (1950).

Pinnules bearing sori of the right age were fixed and stained similarly. However
pretreatment and softening in this case was not necessary.

RESULTS
The number of root tip mitotic chromosomes of all the species and natural hybrids were in
accordance with the expectation and literature (Fig. 1). Meiotic spore mother cells are illustrated
in Fig. 2. Each sporangium of P. setiferum, P. lonchitis and P. aculeatum produced 64 viable
spores. Forty-one bivalents could be observed in the diploid species and 82 in the tetraploid P.
aculeatum. Multivalents were not seen in the tetraploid species.

The meiotic divisions in both triploid hybrids (P. x illyricum “LLS” and P. x bicknellii
“SSL”) differed significantly from the parental species. During the first meiotic prophase the
chromosomes of the two homologous genomes formed bivalents while the chromosomes of the
third unrelated genome remained as univalents. In some meiotic cells of P. x bicknellii (“SSL”)
unpaired chromosome segments as well as loops could be seen on the bivalents at pachytene
(Figure 3.). These observations indicate the different evolutionary history of the two “setiferum”
genomes further on referred to as “S” genome. Although both “S” genomes were originally
derived from P. setiferum, one of them came directly from the diploid species, while the other
one has spent a long time in the allotetraploid P. aculeatum. During this period the “L” genome
originating from P. lonchitis coexisted with this “S” genome in P. aculeatum (Sleep 1966, Vida
& Pintér 1981). Investigations of meiosis of the diploid hybrid P. x lonchitiforme (Halacsy)
Becherer (= P. lonchitis x P. setiferum) show a certain degree of homology between the
chromosomes of the two diploid species (Vida & Pintér 1981), therefore the assumption seems
to be justifiable that in the course of their evolution, some chromosome parts could have been
transferred from chromosomes of the “L” genome to those of the “S” genome and consequently
leading to a gradual change in the chromosomes. The loops seen at pachytene (Fig. 3 c,d) are
presumed to be the visible cytological evidence for this process. Forty-one univalents and 41
bivalents are clearly recognisable at diakinesis and metaphase I. (Fig. 4 a,b).

The homologues separate and move to the poles during the first anaphase of meiosis (Fig.
4 c). However distribution of the univalents occurs at random between the poles, or they form
smaller or greater groups at the equatorial plate and ultimately micronuclei. In the course of the
second meiotic division, the chromosomes split longitudinally into chromatids resulting in four
progeny cells (Fig. 4 d). Accordingly, a whole set of “S” chromosomes and some “L”
chromosomes are included in each member of the tetrad (Fig. 4 e,f,g). Such spores are usually
inviable because of the presence of the incomplete “L” genome (Fig. 5).

D8 FERN GAZETTE: VOLUME 15 PART 1 (1995)

Figure 1. Root tip mitoses of species and hybrids studied.
a) and b): P. setiferum 2n=82; c) and d): P. lonchitis 2n=82; e) and f): P. x bicknellii 2n=123;
g) and h): P. aculeatum 2n=164 (bar=10pm)

POLYSTICHUM x BICKNELLII PROGENY 29

Figure 2. Meiosis of diploid and tetraploid species.
a) and b) P. lonchitis: metaphase I

c) and d) P. setiferum: metaphase I

e) and f) P. aculeatum: metaphase I (bar=10um)

According to Vida (1973) there are six main types of the meiosis in P. x i/lyricum, and
presumably the meiotic processes are similar in the case of P. x bicknellii (Fig. 6). The first and
third types of division are the most frequent; they do not result viable spores. As the number of
the chromosomes of the progeny generation is known for P. x bicknellii, the second and the sixth
type must occur more frequently than the fourth or fifth. From microscopic observations (Fig.
5) the majority of the spores appear to be sterile; however some spores are much larger and may
be presumed to be viable with an unreduced number of chromosomes.

30 FERN GAZETTE: VOLUME 15 PART | (1995)

Figure 3. Pachytene phases of meiosis in P. x bicknellii.
a) univalents and bivalents are distinguishable (bar=10um) b) a part of Fig 3a (bar=10um)
c) and d) loops on bivalents (arrows)(bar=10um)

In order to estimate the percentage of germination, and to raise progeny of the triploid P. x
bicknellii (“SSL”), roughly 2.2 million spores were sown from the hybrid labelled “Pol 1a” and
about 1.5 million spores from the hybrid labelled “Pos 2b”. Only 2 - 3% of the spores
germinated. Some of the prothalli died already by the first cell division, others were unable to
develop into a regularly shaped prothallus, but grew into a ramifying filiform heap. These may
have had an aneuploid number of chromosomes and so consequently were unable to produce
normal gametophytes. A smaller fraction of the gametophytes developed into normal prothalli
with reproductive organs, and by self-fertilisation produced the sporophyte progeny generation
of P. x bicknellii. Apogamy was not observed. It was not possible to keep alive all the sporelings.
Most perished in the early stages of development, although they had been kept under similar
conditions as their surviving companions. Altogether 155 sporelings of P. x bicknellii were
raised (118 from Pol la and 37 from Pos 2b), out of which 84 (73 pol la and 11 Pos 2b) are still
alive at present. The great number of plants that perished may be explained partly by the
inadequate conditions under which they had been kept, but it can also be assumed that some

POLYSTICHUM x BICKNELLII PROGENY 3

Figure 4. Meiosis of P. x bicknellii.
a) and b) diakinesis; c) anaphase I; d) anaphase II; e) and f) late anaphase II; (bar=10um)

represented aneuploid deviations. It is conceivable that prothalli with one or two missing (or
extra) chromosomes could develop reproductive organs and also become fertilised, but
subsequently may fail to tolerate this deficiency in a more complex sporophyte. There was a
significant difference in the rate with which the sporophytes developed. Some of them were so
much retarded that they were unable to develop fertile fronds by the age of ten years.

2} FERN GAZETTE: VOLUME 15 PART 1 (1995)

The best developed individuals reached meiosis in the spring of the second year. On frond
morphology, the majority of the sporophyte progeny resembled P. aculeatum (Fig. 7.), while few
show P. setiferum or P. lonchitis traits (Fig. 8.). Figure 9 shows the silhouettes of two fronds of
triploid progeny. Out of the 84 surviving sporophytes 63 were checked cytologically. Most of
them (59) proved to be hexaploid (2n = 246) (Fig. 10.), and only four were found to be triploid
(2n = 123) (Fig. 11.). So far neither diploids nor tetraploids could be found among the progeny
of P. x bicknellii. Although this fact does not exclude the possibility that diploid or tetraploid
plants can be produced, nevertheless it indicates clearly a greater probability of hexaploid and
triploid F2 plants.

Figure 5. Spores of P. x bicknellii
(bar=100um)

The meiotic processes in the hexaploid P. x bicknellii progeny were much more regular than
those of their triploid parents. Usually 16 spore mother cells (Fig. 12 a) were developed in each
sporangium. The majority of the chromosomes formed bivalents, although some multivalents
and univalents could also be seen (Fig. 12 c,d). The presence of the four “S” genomes explains
the formation of multivalents. Since the association of the four homologues to form a
quadrivalent requires at least three chiasmata, often only trivalents are made leaving the
remaining chromosome as univalent. Well-stained interconnections between bivalents could
sometimes be observed (Fig. 12 b) similar to those seen by Klasterska and Natarajan (1975) in
the course of meiosis of hybrids of Rosa.

The further meiotic division advanced, the greater did the spore mother cells develop out of
synchrony, resulting in different phases of meiosis being visible in the same sporangium (Fig.
12 e). In most cases, meiosis resulted in regular tetrads, and viable spores developed (Fig. 12
gh). However some signs of the hybrid origin still remained. Occasionally a bridge was formed
between the nuclei of the tetrads (Fig. 12 f), or separated univalents could be observed in the
proximity of the nuclei, and finally considerable number of aborted spores were produced (Fig.
12 h).

POLYSTICHUM x BICKNELLIT PROGENY 33

type of results of
meiosis SMC diads__tetrads spores meiosis sporophytes
:
@ sterile a
spores

meee el it—e

by apog.
& large viable 3, P. bick.
“a spores sexual fert:

6x P. bick.

ml) fil sterile
De E —e
by, dp) spores

large and large: 4x P. ac
C25 small small: 2x P. set.

oy viable large x small:
OG

spores 3x PR. bick.

Oxec Me 9. small viable
V P. set. and/or

and sterile

Boe 3 20 snares P. lonch.

+2 ~ &3)< la viable PyaERES
rge '

sexual fertil.:

&) Gx P. dick.

em eee SC SC—i

Figure 6. Possible pathways of meiosis P. x bicknellii (adapted from Vida, 1973.)

SSSS = 41 bivalents, SS = 41 chromosomes, S = 41 chromatids of P. setiferum; LLLL = 41
bivalents, LL = 41 chromosomes, L = 41 chromatids of P. lonchitis. (| or _ = some
chromosomes or chromatids of L genome, SMC = spore mother cell)

The triploid progeny of P. x bicknellii have a totally disturbed meiosis similar to their
parents (Fig. 13); consequently viable spores are absent or very rare. As explained in Figure 6,
triploid plants may have arisen either by apogamy, or sexually, between haploid “S” and diploid
“SL” chromosome sets of prothalli. As the latter requires the simultaneous occurrence of two
events of very low probability, an apogamous origin appears to be more likely.

34 FERN GAZETTE: VOLUME 15 PART 1 (1995)

Figure 7. Silhouettes of 6x P. x bicknellii 1. (aculeatum-like fronds)

POLYSTICHUM x BICKNELLII PROGENY

409

Figure 9. Silhouettes of
3x P. x bicknellii
progeny. i i »

35

FERN GAZETTE: VOLUME 15 PART | (1995)

36

=246)

Figure 10. Mitosis of 6x P. x bickneilii progeny (2n

(bar=10um)

f
A, Vs
INS Wy

Saisie

123))).

Figure 11. Mitosis of 3x P. x bicknellii progeny (2n

(bar=10um)

POLYSTICHUM x BICKNELLII PROGENY a7

Figure 12. Meiosis of 6x P. x bicknellii progeny.

a) 16 spore mother cells b) interconnections between bivalents

c) metaphase I d) explanatory diagram of c) (bivalents in black, univalents outlined,
multivalents streaked) e) asynchronous spore mother cells f) abnormal “tetrad” with bridges g)
16 synchronous spore mother cells h) viable and aborted spores (a: bar=50um; b-f: bar=10um;
g,h: bar=100um

38 FERN GAZETTE: VOLUME 15 PART | (1995)

ae
A oe
go
2 o e ro)
er w

Figure 13. Meiosis of 3x P. x bicknellii progeny. a) metaphase I: 41 bivalents and 41
univalents b) explanatory diagram of a) (bar=10um)

DISCUSSION

In some localities where P. aculeatum, P. setiferum and P. x bicknellii grow together there is an
increased morphological similarity between the two species. On the basis of examination of
meiosis in P. x bicknellii there is a good reason to assume that among the spores resulting from
meiosis some contain exclusively chromosomes of the setiferum genome. The prothalli
developing from such spores could give rise to sporophytes of P. setiferum by _intra-
gametophytic selfing or by crossing with other prothalli of P. setiferum. However the progeny
may deviate morphologically from P. setiferum living in an “unmixed” population because in
the allotetraploid P. aculeatum the “S” genome chromosomes have been coexisting for a long
time with the partially homologous “L” genome chromosomes, and thus some mutual genetic
exchange could have occurred. This hypothesis, however, cannot be justified unequivocally as
up to now only the formation of triploid and hexaploid progeny has been observed. However
this does not exclude the possibility of a rare occurrence of introgression in nature.

The F2 hexaploid P. x bicknellii plants are now fertile. They can be considered to be a new
autoallohexaploid species of Polystichum.

The F2 generation from P. x bicknellii is morphologically very heterogeneous; traits of P.
setiferum, P. aculeatum and even P. lonchitis may be found. It is possible that hexaploid progeny
of deviating morphology may also be found in mixed natural populations.

The triploid members of the new generation may evolve into a line tending towards
apogamy which eventually may result in an apogamous, and therefore future triploid P. x
bicknellii.

ACKNOWLEDGEMENTS
I am indebted to Professor Dr. Gabor Vida for the enthusiastic instructions he gave me
throughout my work, and for critical discussion of many of the points raised in this paper. I have
also to express my acknowledgements to Miss Gabriella Fenyésy for her technical assistance,
and to Dr. Mary Gibby for final correction of the manuscript. Part of this work was supported
financially by the Hungarian OTKA Foundation (No. 2221).

REFERENCES
BROWNSEY, P.J. 1976a. A biosystematic investigation of the Asplenium lepidum complex.
Bot. J. Linn. Soc. 72: 235-269.
BROWNSEY, P.J. 1976b. The origins of Asplenium creticum and A. haussknechtii. New
Phytol. 76: 523-542.

POLYSTICHUM x BICKNELLIT PROGENY 39

DAIGOBO, S. 1972. Taxonomical studies on the fern genus Polystichum in Japan, Ryuku and
Taiwan. Sc. Rep. TKD. Sect. B. 15: 57-80.

-DAIGOBO, S. 1973. Chromosome numbers of the fern genus Polystichum |. J. Jap. Bot. 48:
337-344.

DAIGOBO, S. 1974. Chromosome numbers of the fern genus Polystichum 2. J. Jap. Bot. 49:
371-377.

GHATAK, J. 1963. Observations on the cytology and taxonomy of some ferns from India.
Proc. Indian Sci. Congr. Assoc., 50th Sess. 3. 371-372.

KLASTERSKA, J. & NATARAJAN, A.T. 1975. Stickiness in Rosa meiosos induced by
hybridisation. Caryologia 28: 81-88.

LOVE, A. & LOVE, D. 1961. Some chromosome numbers of Icelandic ferns and fern-allies.
Amer. Fern J. 51: 127-128.

LOVE, A. & SOLBRIG, O.T., 1964. IOPB chromosome number reports I. Taxon 13: 99-110.

LOVIS, J.D. & REICHSTEIN, T. 1968. Uber das spontane Entstehen von Asplenium
adulterinum aus einem natiirlichen Bastard. Naturwiss. 55: 117-120.

MANTON, I. 1950. Problems of Cytology and Evolution in the Pteridophyta. Cambridge
Univ. Press.

MANTON, I. & REICHSTEIN, T. 1961. Zur Cytologie von Polystichum braunii (Spenner)
Fée und seiner hybriden. Ber. Schweiz. Bot. Ges. 71: 320-382.

MANTON, I. & WALKER, S. 1954. Induced apogamy in Dryopteris dilatata (Hoffm.)
A.Gray and D. filix-mas (L.) Schott emend. and its significance for the interpretation of
the two species. Ann. Bot., n.s., 18: 377-383.

MEHRA, P.N. 1961. Chromosome number in Himalayan ferns. Res. Bull. Panjab Univ. n.s.
12: 139-164.

MEYER, D.E. 1960. Zur Gattung Polystichum in Mitteleuropa. Wildenowia 2: 336-342.

MITUI, K. 1975. Chromosome numbers of Japanese Pteridophytes. Bull. Nippon Dental
College, General Education 3: 221-271.

RASBACH, H., RASBACH, K., REICHSTEIN, T., SCHNELLER, J.J., VIDA, G. 1979.
Asplenium x lessinense Vida et Reichst. in der Bayerischen Alpen und seine Fahigkeit
zur spontanen Chromosomenverdoppelung. Ber. Bayer. Bot. Ges. 50: 23-27.

SLEEP, A. 1966. Some cytotaxonomic problems in the fern genera Asplenium and
Polystichum. Unpublished Ph. D. thesis. University of Leeds.

SLEEP, A. & REICHSTEIN, T. 1967. Der Farnbastard Polystichum x meyeri hybr. nov. =
Polystichum braunii (Spennner) Fée x P. lonchitis (L.) Roth und seine Cytologie.
Bauhinia 3: 299-374.

TAYLOR, T.M. & LANG, F. 1963. Chromosome counts in some British Columbia ferns.
Amer. Fern J. 53: 123-126.

VIDA, G. 1963. A new Asplenium (sectio Ceterach) species and the problem of origin of
Phyllitis hybrida (Milde) Christ. Acta Bot. Acad Sci. Hung. 9: 197-215.

VIDA, G. 1965. Ursprung und Systematik der tetraploiden Asplenium-Arten. Bot. Kézlem. 52:
166-167.

VIDA, G. 1966. A magyarorszaégi Polystichumok citologiaja. Bot. K6zl. 53: 137-144.

VIDA, G. 1972. Cytotaxonomy and genome analysis of the European ferns. Symp. Biol.
Hung. 12, 51-60.

VIDA, G. 1973. Polyploid Evolution in Ferns. (Doctoral Dissertation in Hungarian language -
Hungarian Academy of Sciences, Budapest. p.136.)

VIDA, G., MAJOR, A., REICHSTEIN, T, 1983. Relations and evolution in Cheilanthes
(Sinopteridaceae, Pteridophyta) in Macaronesia and Mediterranean area, deduced from
genome analysis of hybrids. Acta Bot. Malacitana 8: 101-126.

40 FERN GAZETTE: VOLUME 15 PART | (1995)

VIDA, G. & PINTER, I.Z. 1981. The rarest interspecific Polystichum hybrid, P. x
lonchitiforme (Halacsy) Becherer (= P. lonchitis x P. setiferum) found in Hungary. Acta
Botanica Acad. Sci. Hung. 27: 455-460.

VIDA, G. & REICHSTEIN, T. 1975. Taxonomic problems in the fern genus Polystichum
caused by hybridization. In Walters, S.M., European Floristic and Taxonomic Studies
pp. 126-135.

WAGNER, W.H. Jr. 1973. Reticulation of Holly Ferns (Polystichum) in the Western United
States and adjacent Canada. Amer. Fern. J. 63: 99-115.

BOOK REVIEW
HONG KONG FERNS (Hong Kong Flora and Fauna Series) by May-ling So. 1994. 159 pp.
Published by the Urban Council, Hong Kong. Paper-back. HK$ 90 (about £8.50) from the
author: Dr. May-ling So., Biology Department, Hong Kong Baptist University, 224 Waterloo
Road, Hong Kong. Fax - 852/2336 1400

This book contains details of 140 of the 214 species of ferns and fern-allies found in Hong
Kong. Each is illustrated by a colour picture of the plant and the majority also include a detail
of a sorus and a scanning electron photograph of a spore. Scientific, Chinese and usually English
names are given together with some general comments about its ecology, occurrence, medicinal
qualities and a reasonable technical description.

The book is easy and pleasant to use and would certainly be helpful in identifying the plants.
It is certainly cheap and I recommend it to anyone interested in the pteridophytes of this part of
the world.

Barry A. Thomas

7
'

THE FERN GAZETTE

. 4 ; 4 r . * ‘" ¥

| FOR CONTRIBUTORS | | fete as At ee See

y x 4
3

- The Editor of The Fern Gazette
Wee Barry re Thomas. oy ;
F _ Department of Botany <4). ze
N ational Museum of Wales 1
a | Cardiff CFI SIMS aon SEPA an Go

ae should — in Mckee ofthe reauied ’

wat i
i te tts,
is J

it | ip a Oe nk : |
7 eg \ sca NUMBERS ony THE GAZETTE, PTERIDOLOGIST. BULLETIN:

de 4

4

b oa by ¥ 5
On ale fo saad from: Ae Ps. iets a are
a a ca +4 MCh Stan ave & oF a
- i 2 Sh Mary Cray ryt a
iY a cs Kent BRS 3LJ
Se Pe” Meath boat e SE des
Sy ete ke Pee ny
£ > eee Pgh
eee elt 0
aR te a
x 4 » . ‘ Ww *
f “8 , es ‘ 44
‘ oe PA rei. yal 1 is
, He Th a) _s
ro G.% - ba ft we ri
A , - a | ‘ ; <
x f % } f)
ie, | ;

. on ay. et of pteridology « are welcome and should be sent Rar its

The British Pteridologi
THE FERN GAZETTE

VOLUME 15 PART 1 1995

CONTENTS

Page

MAIN ARTICLES
Rare and Endangered Ferns of the Western Ghats of South India
— V. S. Manickam 1

On The Ecology and Population Dynamics of a Dutch Population of
Polystichum Setiferum (Dryopteridaceae : Pteridophyta)

— Piet Bremer 11:

The Ecology and Cytology of Brianea Insignis
(Blechnaceae : Pteridophyta)

— A. Aziz Bidin . 21

Progeny Studies of the Fern Hybrid Polystichum x bicknellii
(Dryopteridaceae : Pteridophyta)

— |. Pintér 25

Review 40

THE FERN GAZETTE Volume 14 Part 8 was published on 15 December 1994

Published by THE BRITISH PTERIDOLOGICAL SOCIETY, c/o Department of Botany,
The Natural History Museum, London SW7 5RB

ISSN 0308-0838
Printed by J & P Davison, 3 James Place, Treforest, Pontypridd CF37 1SQ