Canarium odontophyllum
| Dabai (Canarium odontophyllum) | |
|---|---|
| |
| Common names | Dabai, Borneo olive, Sarawak olive, Sibu olive, kembayau |
| Scientific name | Canarium odontophyllum |
| Family | Burseraceae |
| Genus | Canarium |
| Order | Sapindales |
| Native range | Sumatera, Borneo and Palawan (Philippines) |
| Tree size | Usually 8–25 m; potentially to about 35–40 m in forest |
| Fruit | Ovoid drupe about 3–4 cm long, 10–18 g, dark purple to black skin over pale yellow pulp, one three-angled seed |
| Harvest season | November to January in central Sarawak markets |
| Propagation | Seed (variable, males possible); bud grafting recommended for reliable fruiting |
| Years to fruit | About 3–5 years bud-grafted; about 6–8 years from seed |
| Uses | Fresh fruit after warm-water soak; seed kernel edible as a nut |
Canarium odontophyllum, the dabai, Borneo olive, Sarawak olive or Sibu olive, is a fruit tree of the torchwood family (Burseraceae) native to Sumatra, Borneo and the Philippine island of Palawan. [1] The name was first published in the supplement to the Flora van Nederlandsch Indië in 1859, with some regional records citing 1861; the accepted treatment also recognises the earlier names Canarium beccarii, Canarium multifidum and Canarium palawanense. [1][2] In Brunei and Sabah the fruit is called kembayau. [3] The drupe is a seasonal delicacy in Sarawak, where whole ripe fruit is soaked in warm water to soften the pulp before eating. [4]
Description[edit | edit source]
The tree is resiniferous, with a straight trunk branching a few metres above the ground and buttresses on older trees. [5] In the commercial Sarawak stands trees commonly grow 8–25 m tall with a trunk girth of 15–60 cm; [6] botanical records describe medium to fairly large trees to about 35 m with a branchless bole to 18 m and a trunk up to 60 cm diameter, [2] and to about 36 m in Philippine material. [7] Reviews list potential heights of 30–40 m and an economic lifespan of about 40 years. [3]
Leaves are pinnate with a terminal leaflet and 3–8 pairs of leaflets, each leaflet 9.5–28 cm long and 4–11 cm wide, acuminate, with dentate to serrate margins, hairy below and on the midrib above. [5][2] Other descriptions count 7–17 leaflets. [2] A Philippine botanical profile describes leaves to 40 cm by 10 cm with strongly toothed margins; the epithet odontophyllum means "toothed leaf". [7]
Flowers are unisexual and borne in lax axillary panicles; male flowers measure 4–7 mm and female flowers 8–9 mm, with six stamens. [2][7] The species is androdioecious: pollen-bearing and fruit-bearing plants are separate. Male plants carry long, thin inflorescences of small flowers; hermaphrodite plants carry short, thick inflorescences with considerably larger flowers at the tip. [5][8] Male plants do not fruit; they provide pollen for the hermaphrodite flowers. [8] Flowers with well-developed stamens and under-developed pistils have also been recorded. [5] One review instead calls the species monoecious [9], and a Sarawak gardening column uses the looser term dioecious [10]; the terminology varies between authors for what the field studies describe as the same male/hermaphrodite arrangement.
The fruit is an ovoid to ellipsoid drupe, slightly triangular in cross-section, with a single large seed. [2][6] Across the main Sarawak growing districts the fruit measured about 3.0–4.0 cm long, 2.2–3.0 cm across and 10–18 g, [4] while a Sarawak morphological record gives 35–40 mm by 20–25 mm with an edible mesocarp 6–8 mm thick. [8] Orchard fruit from Papar, Sabah averaged about 9 g, with the seed contributing about 61% of the fresh weight and the flesh about 0.4 cm thick, [11] and the released-clone tables list fruit 25–35 mm long by 17–20 mm diameter. [6] One analysis partitioned the fruit into roughly 61% pulp, 6% peel and 37% kernel. [12] The thin skin ripens dark purple to black, sometimes dark red — the less common "red dabai" of the Sarikei area — over pale yellow to golden pulp 3–7 mm thick. [4][5][6] A hard, thick endocarp encloses one three-angled seed with three chambers; the seed itself is usually discarded. [4]
Cultivation[edit | edit source]
Soil and water[edit | edit source]
Native trees stand along river banks in the Sibu, Sarikei, Kapit and Limbang divisions of central Sarawak, outside swamps and coastal sands, [5] in lowland primary forest to about 450 m [2] and on sites recorded to about 700 m, [8] within the wet tropical biome. [1] The habitat is perennially moist, free-draining riverine and forest soil. [5] As a Canarium, it is reasonable to begin with the genus pattern of moist, rich, deep, crumbly, organically sandy loam with a pH of 4.5–6.5, tolerating alkaline conditions up to about pH 7.4; this is a genus-level inference from a review, so confirm it for C. odontophyllum before treating it as a fixed requirement. [3]
Sun and humidity[edit | edit source]
The species belongs to humid lowland forest rather than dry open savanna. [1][2] A member-maintained sun and shade database on the Tropical Fruit Forum lists dabai as thriving in full sun, subpar in light shade and poor in moderate or deep shade; the compiler noted that plants in naturally sunny regions can be more sun-sensitive, so the list is a general guide for mature plants rather than a tested schedule. [13] In the UNIMAS grafting work, pruning the rootstock's top growth and growing the grafted plant in a sun-exposed area increased bud break. [14]
Seasonal changes[edit | edit source]
Male trees start flowering at 4–5 years after planting, while hermaphrodite trees flower and bear later, at about 6–8 years. [5] The fruit is harvestable about 120 days after flowering. [5] In central Sarawak markets fruit is available roughly November to January [11] (October to January in a postharvest account [5]), and a review records seasonal peaks in July–August and November–December. [3] The main crop therefore falls in and just after the wettest months of the Borneo year; where the wet season is unreliable, irrigation through fruit development is the critical period, because the crop is highly perishable and the tree is native to perennially moist lowland habitat. [11][5]
Propagation[edit | edit source]
Seed is the traditional route and still the most common, but it is a sex gamble: seedlings cannot be sexed at planting, and about half turn out to be pollen-bearing males. Sex becomes apparent only at reproductive maturity, around four years after planting, and the established Sarawak practice has been to grow seedlings for four or more years and then remove the males. [8] For this reason the Sarawak Department of Agriculture and the Agriculture Research Centre Semongok recommend asexual propagation — bud-grafted hermaphrodite plants — and describe seed propagation as producing variable traits and male trees. [6][15] A Universiti Malaysia Sarawak research group, however, reports that cutting and grafting are still difficult and that seeds remain the preferred route in practice, where the species is widely propagated from seed. [8][15] Both statements are current: institutional guidance favours budding, while day-to-day propagation still relies heavily on seed.
Budding responds to scion wood and light. In the UNIMAS propagation trials, bud-grafting succeeded better when scions came from hardwood, and pruning the rootstock's top growth while exposing the grafted plant to sunlight increased bud break; in micropropagation, solid agar medium was favourable and shoot tips were the more promising explants, while different PPM surface-sterilisation treatments made no significant difference. [14] Grafted material is the reliable route to a known-fruiting tree: bud-grafted hermaphrodite plants come into fruit at about 3–5 years, against 6–8 years for seedling hermaphrodites. [5]
Flowering, fruiting, and harvest[edit | edit source]
Fruiting depends on having hermaphrodite plants, because male trees bear only pollen, and the commercial practice is to plant bud-grafted hermaphrodite material and remove male trees from the field. [8][6] Molecular work at UNIMAS identified a RAPD fragment (DH272) present in all hermaphrodite samples tested, converted it to a SCAR marker, and described five SNPs and a TaqI CAPS site that may eventually allow seedlings to be sexed before maturity; the authors stress that the marker system still needs validation. [8]
Yield develops with age. The released clones begin with about 10 kg per tree and rise to 80–100 kg per tree at 10+ years, [6][15] and a review places mature-tree yields at 50–300 kg a season. [9] An 800 kg figure for fully mature trees appears in the literature but traces to a secondary citation, so treat it as exceptional rather than typical. [3] Institutional estimates put a single mature tree's gross annual income at least at MYR 9,000, with 12 m by 12 m spacing. [5]
Fruit is picked when the skin has turned from pale to dark purple. [4][10] It is extremely perishable: shelf life is about three days at 27 °C, with the skin wrinkling as moisture is lost, [11][7][16] and respiration is very high — about 1,400 mL of CO2 per kg per hour at 20 °C — which explains the short window. [11] Packing fruit in sealed plastic bags generates heat and cooks it in transit, so a Sarawak gardening column recommends loose paper bags, pickling or freezing for journeys. [10] Freezing preserves fruit for at least a year, retaining acceptable appearance and flavour when the fruit is blanched in boiling water for about five minutes before use. [6]
Fruit and uses[edit | edit source]
Whole ripe fruit is eaten after a warm-water soak: five to ten minutes in warm water softens the pulp, [4] a postharvest chapter recommends about 15–20 minutes at roughly 50 °C, [5] and the Sabah laboratory study used 15 minutes at 60 °C, measuring firmness falling by about 92% while soluble solids rose by 580%. [11] The softened fruit is eaten raw, often seasoned with salt, sugar, pepper or soy sauce, and commonly with rice. [4][9] Tasters compare the flesh to avocado — creamy, fatty and slightly nutty [3][7][9] — and on the Tropical Fruit Forum one member called it "something like a cross of Avocado and olive" and very filling. [17] A paste made from the flesh keeps up to about a month in a household refrigerator. [5]
The seed is usually discarded, but the kernel is edible: cracked open it tastes almond-like, [10] and boiling it for about ten minutes makes a nut snack. [9][7] Kernel dietary fibre can run as high as 22%. [3]
Lipid is the major macronutrient of the edible portion — 21.2–25.8 g per 100 g fresh weight across the four Sarawak districts studied — with protein rich in aspartic and glutamic acids and calcium, sodium and potassium the predominant minerals. [4] Institutional records list, per 100 g of fresh edible portion, 339 kcal, 41.3 g moisture, 3.8 g protein, 26.2 g fat, 22.1 g carbohydrate, 4.3 g crude fibre, 2.3 g ash and 810 mg potassium. [6][15] Pulp oil is about 44% saturated fatty acids — roughly 42% oleic, 36% palmitic and 12% linoleic — while kernel oil is about 61% saturated (palmitic dominant) with measurable vitamin E; the investigators considered both oils suitable cooking-oil or solid-fat candidates. [12]
Pests and diseases[edit | edit source]
The Sarawak programme describes dabai as relatively free from serious pests and diseases, an observation its authors attribute to geographical isolation rather than to controlled trials. [15]
Cultivars and selections[edit | edit source]
Two selected clones dominate the Sarawak commercial programme. Laja and Lulong were selected by the Agriculture Research Centre Semongok and launched in 2006; both are vigorous and begin bearing about five years after planting. [6] Laja bears the larger fruit — individual fruit 18.9 g and 4.5 cm long, flesh 0.35 cm thick, seed 7.7 g, edible portion 61.5%, with a triangular seed and concave sides — while Lulong fruit weigh 13.9 g and reach 3.6 cm, with flesh 0.31 cm thick, a 5.0 g seed, 64.0% edible portion and a rounded seed with convex sides. [6] Laja is therefore the choice for maximum fruit size and Lulong for the slightly higher edible fraction; the Department of Agriculture recommends both for vigorous growth and creamy, bright-yellow flesh with a slight sour tinge. [15][10]
A Sarawak gardening column credits Agriculture Department officer Harry Munjan with the first successful dabai budding in the 2000s and with introducing Laja and Lulong on his own farm in Sri Aman. [10]
Other names circulate as regional selections — Song, Kapit, Intermediate, Egg Yolk, Tarat, Red Dabai and Pulau Keladi — identified by private nursery operators; they have no published cultivar descriptions or trial data, so treat them as nursery labels rather than formally registered cultivars. [6][9] The red dabai of Sarikei is the colour variant analysed in the original compositional studies, in which purple fruit from Kapit showed the highest measured phenolics, flavonoids and antioxidant activity. [4]
References[edit | edit source]
- ↑ [3] Hamzah, M.H., Basri, M.S.M., Ali, M.M. et al. (2022). Exploring Dabai (Canarium odontophyllum), Indigenous Fruit of Borneo: A Review of Nutritional Values, Potential Uses, Emerging Application in Essential Oil Processing, and Health Benefits. Plants 11: 2646.
- ↑ [4] Chew, L.Y., Prasad, K.N., Amin, I., Azrina, A. & Lau, C.Y. (2011). Nutritional composition and antioxidant properties of Canarium odontophyllum Miq. (dabai) fruits. Journal of Food Composition and Analysis 24(4-5): 670-677.
- ↑ [5] Dabai (Canarium odontophyllum Miq.) — Ding, P. (2011) postharvest chapter reproduced on ScienceDirect Topics ('Canarium - an overview').
- ↑ [6] Brooke, P., Lau, C.Y. & Razili, R.M. (2013). Experience in commercialising of Canarium odontophyllum Miq.: A potential superfruit of Sarawak. Agriculture Research Centre Semongok (Department of Agriculture Sarawak), Superfruit Symposium 2013.
- ↑ [8] Ting, J.C., Ho, W.S. & Tawan, C. (2017). Flora morphology and sex specific marker development of a Sarawak's specialty fruit species Canarium odontophyllum. International Journal of Development and Sustainability 6(11): 1621-1637.
- ↑ [9] Mundi, M., Rawi, M.H., Saupi, N. & Sarbini, S.R. (2022). Mini-review: phytology of Dabai (Canarium odontophyllum) as a potential functional food. Food Research 6(1): 296-303.
- ↑ [11] Ding, P. & Tee, Y.K. (2011). Physicochemical characteristics of dabai (Canarium odontophyllum Miq.) fruit. Fruits 66(1): 47-52.
- ↑ [12] Azlan, A., Prasad, K.N., Khoo, H.E., Abdul-Aziz, N., Mohamad, A., Ismail, A. & Amom, Z. (2010). Comparison of fatty acids, vitamin E and physicochemical properties of Canarium odontophyllum Miq. (dabai), olive and palm oils. Journal of Food Composition and Analysis 23(8): 772-776.
- ↑ [14] Kho, P.K. (2006). Vegetative propagation of Dabai (Canarium odontophyllum Miq.) through conventional and in vitro methods. Final Year Project Report, Universiti Malaysia Sarawak (UNIMAS repository eprint 18848).
- ↑ [15] The dabai story: experience in commercializing an underutilized fruit — TFNet (adapted from the ARC Semongok presentation).
- ↑ [16] Ariffin, S.H., Shamsudin, R. & Mohamed Amin Tawakkal, I.S. (2020). Dabai Fruit: Postharvest Handling and Storage. Advances in Agricultural and Food Research Journal 1(2).
Image credits[edit | edit source]
- File:Canarium odontophyllum.jpg — Fruit of Canarium odontophyllum (subject from the file-page description: fruit on a branch). Creator: Song GK, CC0 1.0 (license). File page: Wikimedia Commons. Attribution: Song GK, CC0, via Wikimedia Commons.
