Terrestrial orchids in Malaysia

(Japanese version is HERE .)

Malaysia is known for her lush tropical rainforests covering the large portion of the peninsular and the northern coast of the island of Borneo. Malaysia is also known for her beautiful orchid species ( Flora of Mount Kinabalu, Sabah, Malaysia and Biodiversity and Conservation of Mount Kinabalu, Sabah, Malaysia ) such as the Vanda and Phalaenopsis found in their natural habitats as well as in cultivation. With the country's fast development towards industrialization, large tracts of the rainforests, like elsewhere, have been lost due to lumbering and other human activities.
Orchids belong to the largest family of flowering plants, the Orchidaceae, which includes some 19,500 species in 804 genera ( Dressler, 1993 )D Of these, 854 species covering 141 genera are said to be indigenous to Peninsular Malaysia ( Seidenfaden and Wood, 1992 ) and over 1400 species in 147 genera to Borneo (Chan et al. 1994 ). Many of the orchid species, for example, the Paphiopedilum and Vanda are so showy that they are said to be in extinction in their natural habitats due more to horticultural collections than developmental activities. Even other inconspicuous orchids are also endangered because of their horticultural value as rare plants. As such, most of the orchid species are now listed as endangered species ( Pritchard 1989, Reid and Miller 1989, Waite 1989, Wood 1989 ).
Although terrestrial orchids are less popular as commercial or ornamental plants compared to epiphytic orchids, many of them are equally attractive and worth preserving as germplasm for breeding purposes. Among these, Spathoglottis plicata, Arundina bambusifolia and Calanthe triplicata were selected for studies on conservation, breeding and artificial micropropagation. The justifications are ; 1) they are hardy and beautiful as pot plants or as garden orchids ; 2) because they are not as popular as Phalaenopsis or Dendrobium, they are not propagated in vitro but collected direct from their natural habitats, hence making them endangered ; 3) they are widely distributed both in Japan and in South East Asia and research fields are still available.
Ecological survey of the wild orchids ( Wells and Willems 1991 ) is useful for not only their conservation but also their cultivation. In the present study, the authors focused on the genus Spathoglottis considering its presence in the natural habitats as well as the ecological conditions in which it grows.
The genus Spathoglottis consists of about 40 species, widely distributed in the regions from India, southern Japan and China, down through the islands of the Pacific and northern Australia ( Seidenfaden and Wood, 1992 ). In Malaysia, six and seven species of the genus Spathoglottis grow wild in peninsular and Borneo, respectively. Spa. plicata is the most common species in the genus found growing either in the lowlands or elevated areas of Malay Peninsular and Borneo, Malaysia and Iriomote Island, southern part of Japan. The flowers of Spa. plicata can be in different shades of purple including white, as well as variations in shapes which attract collectors.

Ecological survey
Two ecological surveys were carried out at Genting Highlands in Peninsular Malaysia mainly on June 26, 1996 and Mt. Kinabalu in the island of Borneo on June 29, 1996. Fig. 1 shows the points of the ecological surveys conducted. The data were compared with those previously collected from Iriomote Island, Okinawa, Japan (Tanaka and Mizutani, 1995 ). Quadrats were set at the locations where Spathoglottis species were found to be growing wild. The considerations taken into account in each quadrat were habitats, altitude, exposure, land inclination, light intensity, soil type, soil humidity, vegetation and coverage of plants.

‚PDClimate and general vegetation
In the present study, the authors surveyed the ecological conditions of the wild orchids focusing the genus Spathoglottis at two locations : Genting Highlands in Peninsular Malaysia ( West Malaysia ) and Mt. Kinabalu in Borneo ( East Malaysia ).

Mt. Kinabalu
Kinabalu Network
Sabah Tourism - Mt. Kinabalu - infoSabah
A Guide to Mount Kinabalu Summit Trail
Mt. Kinabalu is the highest peak ( 4,101m ) in Southeast Asia and is known for its well preserved complete spectrum of plant life, which embraces tropical lowland rainforest, tropical mountain forest, tropical moss forest and tropical alpine vegetation all packaged in one locality. In each vegetation, incredible biodiversity or species rich forest were observed and over half of the species growing above 900 meters are said to be endemic.
At elevation lower than ca. 900 m elevation, hot climate and an average annual rainfall of 2500 mm favors tropical lowland rainforest with its its huge Dipterocarpus trees and biodiversity with various foliage levels under the top canopy. Between 900 m and 1,800 m elevation cooler temperature, the better light penetration and higher moisture produce denser ground cover and an abundance of epiphytes such as orchids and mosses growing on tree trunks than the lowland forest. At 1,588m ( Park headquarters ), daily temperature varies from 20 C to 13 C at night.
Tropical moss forests started at a distinctively cold 1,800 m elevation where the annual rainfall hit 4570 mm and thick mosses, lichens, orchids were found hugging to stunted tree trunks. As a matter of fact, It was difficult to find a tree without any epiphytic orchids. Several Rhododendron and Nepenthes ( Pitcher plant ) also grew wild attracting the interest of the horticulturists. Beyond the moss forest, under extreme temperature, violent winds and driving sleets at the summit zone, there exist tropical alpine forest with low diversity plant life.

Genting Highlands
Genting Highlands is situated 50 km from Kuala Lumpur. The Highlands has grown to become a biggest highland resort. After 1969, it has also become the main recreation center in Malaysia, which attracts not only the casino players but also the people who want to escape from the hot and humid lowlands, because at 1,711 meters above sea level, the air is cool and invigorating. The weather is generally very cool whereas in the evening it can get misty all year round.

2DQuadrat survey
In each location, the survey found two Spathoglottis species :Spa. plicata Blume and Spa. aurea Lindl., and Spa. plicata and Spa. microchilina Kraenzl., growing wild. These species are among the known six species of the genus found in Peninsular Malaysia ( Teo 1995 ), and among seven species found in Borneo Island ( Chan et al. 1994 ), respectively.

Spathoglottis plicata
Table 1 is a summary of the conditions of the quadrats showing the habitats in which the Spathoglottis were found. In both locations, the species were found in open spaces with high light intensity ( 90 Klux ) generally on the slopes formed by road construction in the mountainous area. In Malaysia, even Spa. plicata grew wild at high elevation, but generally not higher than ca. 1,500 m. In Iriomote Island, Japan, Spa. plicata was found in the lowland at about 60 or 240 m above sea level. In the lowland of Malaysia, encroachment of industrial development as well as large-scale plantations have minimized the natural habitats for Spa. plicata.
In Iriomote Island, Spa. plicata was frequently found growing among two other species sharing similar habitat, Dicranopteris, a semi-climber fern, and Arundina, a tall grass terrestrial orchid with Cattleya-like flowers. In Genting Highlands, both of these species looked stronger and bigger ( about 2 m ) than those in Japan and seemed to dominate the places where Spa. plicata had grown.
The quadrat, Myg-1, is the road-side shoulder at 1170 m elevation in Genting Highlands next to the dense Dicranopteris and Arundina grassland where Spa. plicata was not found. There was one Spa. plicata plant recovering from the damage of the shading by removing the canopy of the tall grasses but in return the mowing also severely damaged the plant. The open spaces consisted of short grassland of Imperata cylindrica which was most dominant, Mimosa pudica, Cyperus spp. ( Table 2 and Fig. 2 ) and Ipomea cairica surrounded by Cyathea and Ficus undergrowth (data not shown ).
The quadrat, Myg-2, was a cut-slope of a road at 830 m elevation where vigorous Spa. plicata were found growing. They were blooming flowers, bearing seed pods and dispersing seeds simultaneously. It seemed that Spa. plicata was more competitive against Emilia sonchifolia, Crassocephalum ciepidioides although some climbering plants such as Mikania micrantha were seen to be shading them ( Table 3 and Fig. 3 ). However, the tall competing species such as Dicranopteris and Arundina or woody plants had not established at the place yet.
In the island of Borneo, the quadrat, Myk-1, was located at 1475 m elevation along a road to Mt. Kinabalu. At this location, Spa. plicata survived among Arundina graminifolia grassland ( Table 4 and Fig. 4 ). The habitat was too humid for other weed species to grow except for three small fern species and Imperata cylindrica. The A. graminifolia there was seen bigger ( 2.5 m ) than those in the Peninsular and in Iriomote Island although rather scattered in existence. It seemed that Spa. plicata plants had enough sun for normal growth and development. This observation tends to imply that Spa. plicata had survival strategies making it a leading plant species in succession ; 1) It invades the open spaces formed by development such as road construction or natural disaster such as landslide ; 2) It is taken over by taller shrubs, woody plants or even grasses depriving it from direct sunshine ; 3) It easily sets seed pods ( capsules ) by self-pollination ( data not shown ) bearing thousands of minute winged seeds that move to new habitats. Teoh ( 1989 ) also reported that Spa. plicata seeds were recovered after thirteen years after the famous eruption ( 1883 ) of Mt. Krakatoa, Indonesia, which destroyed every flora on the island. Unlike other orchid species, Spa. plicata spreads its distribution along with land development, especially road construction. While the cultivation of Spa. plicata is fairly easy. Being an attractive species, the Spa. plicata becomes easily vulnerable to collection by plant collectors for horticultural purposes. Comparing with Iriomote Island, one of the Japanese National Park, the lowland of the Peninsular Malaysia is much developed, making Spa. plicata more endangered.

Spathoglottis aurea Lindl. and Spa. microchilina Kraenzl.
In the survey, the authors found two other Spathoglottis species in the Malay Peninsular and Borneo, both of which bear golden yellow flowers. The distributions of the two species did not overlap with Spa. plicata. They were found growing wild at elevation higher than 1,500 m above sea level. Generally the temperate, higher than 1,500 m above sea level, is too low for the tropical lowland plants and the flora of the two locations were quite different from each other.
Spathoglottis aurea Lindl. was also found growing in the Myg-3 on a road-cut slope ( 1,540 m ) to the Genting Highlands ( Table 5 and Fig. 5 ). It grew with Nepenthes spp. Sphenomeris chinensis and some other herbaceous species. It seemed to grow in avoidance to competition with Dicranopteris linearis. However, no Spa. aurea was found near the top of the Genting Highlands, whereas some Spa. aurea plants were found on the top of Fraster's Hill, at 1,524 m above sea level, which located 100 km north of Kuala Lumpur, though quadrat survey was not carried out there. Genting Highlands seemed to be too developed as a mountain resort or recreation center to survive the species.
Spathoglottis microchilina Kraenzl. was found In the quadrat, Myk-2 ( 1570 m ), in the island of Borneo, where the headquarters of Mt. Kinabalu is located near by. In this location, Spa. microchilina grew with two other terrestrial orchid species, Arundina graminifolia and Calanthe triplicata, as well as some ferns such as Lycopodium complanata and grasses such as Cruculigo latifolia ( Table 6 and Fig. 6 ). The survey found that the habitat for Spathoglottis is very limited especially in the tropical forest like in Borneo although development processes such as road construction prepare new habitats for the Spathoglottis. However, the species seemed to be endangered by both weeding and competition with other plant species even though Mt. Kinabalu itself is well conserved from the horticultural collection.
Although certain climatic conditions of the temperate zone are somewhat similar to those of the corresponding elevation of the lower latitude, the climate of tropical highland is entirely different from that of subtropical lowland. In tropical highland, climatic conditions throughout the year are not very hot or very cold. Therefore, the plants from the tropical highlands are generally very difficult to survive as they are not tolerant to cold and heat conditions even similar to the winter or summer time of the Temperate Zone. These two Spathoglottis species are also said to be very difficult to grow in the tropical lowland.
The authors have been working on the breeding and in vitro propagation for a long time and realized that the micropropagation technique is also useful for the conservation of the wild orchid species. However, special attention must be made not to disturb the natural condition when the artificially propagated orchids are released ( Tanaka and Mizutani 1995, 1996 ). Research in this aspect is needed not only to find the germplasms ( Uesato et al. 1981 ) for the breeding of the ornamental orchid cultivars but at the same time formulate for the conservation of the wild orchid species.

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