Germination and seedling survival in kemenyan, styrax benzoin

Styrax benzoin Dryand var. benzoin is atypical of Malaysian forest trees as its, seeds are dormant for more than 7 months after fruit fall. Under natural conditions the woody endocarp cracks after 7 - 9 months and the radicle and hypocotyl then emerge. Dormancy is not imposed by the presence of inhibitors, immaturity of the embryo nor special requirements of light or temperature, as after removal of the endocarp germination begins. The endocarp therefore imposes dormancy either mechanically or by preventing the entry of water. The seedling becomes dependent on its photosynthesis at the 3-leaf stage about 4 - 6 months after germination, when the reserves from the seed in the form of starch in the hypocotyl are exhausted. Seedling mortality is high with 22.5% survival after 1 year, 7.1% after 2 years and none after 3 years. The largest single cause of mortality is mechanical damage (34%) which includes death caused by falling trunks and branches, by being covered by leaf litter or from trampling; followed by mortality during the germination phase (27%) such as the hypocotyl being gnawed, failure of the endosperm to be cast off or failure to root; fungal wilt (24%) and failure to sustain growth (15%). No seedling died as a direct result of insect damage. Difficulties in assessing insect damage are discussed. 19% of seedlings had spiders' nests under their leaves which resulted in a 2 - 43% reduction of photosynthetic surface. A combination of annual fruiting and a proportion of seedlings that persist for more than a year ensures that at any time there is a supply of seedlings ready to grow into a gap should one occur in the vicinity

Floristic Components of the Ground Flora of a Tropical Lowland Rain Forest at Gunung Mulu National Park, Sarawak

The floristic components of the ground layer at the Gunung Mulu National Park, Sarawak, are described. These components are associated with microhabitats. The microhabitats of the riverine system include the shallow stream, rocky banks and banks of larger rivers, and those of the shaded forest include permanently wet areas, rocky litter-free slopes, steep litter covered slopes, surfaces of logs, roots or rocks and the flat well-drained alluvial forest. Possible causes of the uneven distribution of the ground layer species of the flat well-drained alluvial forest are discussed. The species composition of this alluvial forest is compared with other published reports from the Danum Valley, Sabah and Pasoh Forest Reserve Malaya, and with some other lowland forest types such as kerangas and peat swamp forest in Sarawak. The phenomenon of iridescence and variegation of leaves is briefly noted

Notes on the natural history of the Johore banana Musa gracilis holttum

Musa gracilis is the only wild banana species in Johore, Malaysia. In Kelantan and Trengganu it grows together with M. acuminata Colla. M. gracilis and M. violascens Ridley (in section Callimusa) are compared. Both are endemic to Peninsular Malaysia but their geographic distribution does not overlap. The anatomy of the seed of M. gracilis is described and the function of the chalazal mass is discussed. Growth (increase in stem height and rate of leaf production), its ecology and conservation status are also mentione

Asystasia (Acanthaceae) in Malaysia

Three taxa of Asystasia, the naming of which has been confused, occur in Peninsular Malaysia. None is native. A. nemorum Nees (syn. A. intrusa Blume, non (Forssk,) Nees) from Java has only been collected from Penang and Singapore. A. gangetica (L.) T. Anderson is widespread and is represented by two subspecies: a large-flowered taxon, subsp. gangetica (syn. A. coromandeliana Nees) which is a long-established introduction from India and a small-flowered taxon, subsp. micrantha (Nees) Ensermu (syn. A. intrusa (Forssk.) Nees) which is a recent introduction, probably from Africa. A key to the three taxa in Malaysia is provided

Strategy to Conserve Maximum Biodiversity of Limestone Flora in Peninsular Malaysia

The need to exploit limestone products for national development impacts on the conservation of rare and endangered limestone species. To minimise this impact it is necessary to identify which of the 570 limestone outcrops have high conservation importance and whether they have narrowly endemic and/or endangered limestone species. In the absence of detailed checklists for each outcrop, the Gesneriaceae is selected as being biodiverse on limestone, being well collected and outstanding in the number of endemic species and/or species restricted to limestone for mapping. Of the 210 species in the 25 genera of Gesneriaceae in Peninsular Malaysia, 42 species belonging to the genera Damrongia Kerr ex Craib, Emarhendia Kiew, A.Weber & B.L.Burtt, Epithema Blume, Microchirita (C.B.Clarke) Yin Z.Wang, Monophyllaea R.Br., Ornithoboea Parish ex C.B.Clarke, Paraboea (C.B.Clarke) Ridl., Senyumia Kiew, A.Weber & B.L.Burtt and Spelaeanthus Kiew, A.Weber & B.L.Burtt grow on limestone hills. Of these 42 species, 28 are endemic and 16 are restricted to a single or adjacent hills. Mapping their distribution shows that in common with other families there are three distinct phytogeographical provinces (the Northern Province, Perak Province and the Asian Intrusion) but that the narrowly endemic species do not cluster on particular hills, nor does their distribution coincide with those of other narrowly endemic species in other families. This illustrates that a network comprising a large number of hills, not only those within the three provinces but also all those harbouring narrowly endemic species that are at risk of extinction if not conserved, is necessary to maximise conservation of the biodiversity of the limestone flora

Optimum Substrate for the Establishment of the Epiphyte Dischidia nummularia (Asclepiadaceae)

Brick fragments or wood crumbs (which are substrates with good water retention and aeration) with the addition of nutrients are optimum substrates for the establishment of seedlings of the epzphytic Dischidia ·nummularia. Seeds of D. nummularia, when moistened show 100% germination. Germination is rapid - the radicle is fully grown within a day and the cotyledons emerge within four to five days. Subsequent seedling growth, especially for root system development, was better on brick fragments or wood crumbs than on sand indicating that good water retention and aeration are necessary for seedling establishment. Within an eight-week period, seedling growth on substrates low in nutrients was slow compared with substrates where commercial fertilizer was applied in the recommended amount for epiphytic orchids. The height and number of leaves was roughly doubled and the total dry weight increased between three and fourfold. Further, with brick fragments as a substrate, addition of nutrients resulted in a more extensive root system

Checklist of vascular plants from Batu Caves, Selangor, Malaysia

The vascular plant flora of Batu Caves, a tower karst limestone formation, includes 269 species; 51 species (19%) are Peninsular Malaysian endemics and 80 species (30%) are calciphiles of which 56 (21%) are obligate calciphiles and 26 species are obligate calciphiles endemic to Peninsular Malaysia. Four taxa are endemic to Batu Caves itself. That Batu Caves harbours a sizeable fraction (21.4%) of Peninsular Malaysia’s limestone flora underlines the need for detailed checklists of each and every limestone hill to enable adequate planning of conservation programmes to support biodiversity. Because botanical collecting began in the 1890s, Batu Caves is important as the type locality of 24 plant species. Land-use pressures have over time eliminated the surrounding native vegetation, leaving the flora vulnerable to aggressive weedy and alien species. Although designated as a Public Recreation Area, its protection status needs to be enforced and the boundaries clearly marked

The Flavonoids of Orophea polycarpa A. DC. (Annonaceae)

Investigation on the neutral fraction of the leaves of Oraphea polycarpa A. DC. led to the isolation of two flavonoids identified as 2'-hydroxy-4,4',6'trimethoxychalcone and 5,7,4'-trimethoxyflavanone

A contribution to the phytochemical survey of Peninsular Malaysia

Specimens of 216 plants representing 150 genera and 50 families were collected from four areas in the western and central parts of Peninsular Malaysia. The leaves ofeach species were screened for alkaloids, steroids and triterpenes, and for saponins. 28 specz'es (13%) gave a positive test for alkaloids, 86 (40%) for saponins and 55 (25%) for triterpeneslsteroids