Gnetum gnemon
Gnetum gnemon
Safety & Hazards
None known
Cultivation Details
Grows best in humid tropical areas at elevations up to 1,200 metres[1, 2]. Very tolerant of different levels of rainfall, succeeding with a mean annual rainfall in the range 750 - 5,000mm[2]. Prefers a position in semi shade in a humus-rich, moist soil[1]. Tolerates full sun[3]. Succeeds in heavy shade[4]. Succeeds in a wide range of well-drained soils, preferably slightly acid to neutral, but tolerating calcareous rocks[3]. Tolerant of low fertility soils[3]. Able to tolerate drought for some months, assuming some soil moisture retention or irrigation during dry season[3]. Tolerant of strong winds, so long as they do not carry salt spray[3]. Plants are deeply rooted with a strong tap root system[2]. The plant exists in several varieties, in particular there is the tree form (var. Gnemon) and three shrub forms (vars., brunonianum, griffithii and tenerum) The cultivated trees belong to Gnetum gnemon var. Gnemon and are larger, with larger fruits[2]. Melinjo has the ability to improve nitrogen levels in the soil due to its mycorrhizal associations with the ectomycorrhizal fungus Scleroderma sinnamariense[2]. In experimental conditions, mycorrhizal inoculation appears to enhance seedling growth under shaded conditions in acidic soils[2]. A dioecious plant, male and female forms need to be grown if seed is required. A coupled process of double fertilization and post-fertilization endosperm formation occurs in the genus Gnetum. However the product of the second fertilization event in Gnetum is diploid and expresses the developmental programme of an embryo. In G. Gnemon, egg cells are not formed and maternal provisioning of the embryo-nourishing female gametophyte takes place entirely after fertilization. The lack of differentiated egg cells in G. Gnemon is unparalleled among land plants, the biological significance of double fertilization that does not form endosperm, in Gnetum, is currently unknown. This process may be biologically neutral. Seeds produced three times yearly in Indonesia, March-April, June-July and September-October. The strobili are visited by nectar-seeking moths of Pyralidae and Geometridae. The sticky pollen of Gnetum attaches on proboscides and antennae of these moths. Lack of showy petals, an apparent disadvantage in entomophily is compensated for by floral fragrancy
Propagation
Seed - best sown in situ[2]. Daily watering of the sand and seed mixture will hasten germination, possibly to three months[2]. Without a pre-germination treatment, germination may be 1-2% in 6 months and may reach 100% in 12 months[2]. Air layering[1]. Short cuttings, taken beneath a node[1]. Cite as: Tropical Plants Database, Ken Fern. tropical.theferns.info. 2026-02-20. <tropical.theferns.info/viewtropical.php?id=Gnetum+gnemon>
Pollinators
Moths
References
- [1]The New RHS Dictionary of Gardening. 1992. — Huxley. A. · MacMillan Press · 1992 · ISBN 0-333-47494-5 ↩︎Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
- [2]World Agroforesty Centre — http://www.worldagroforestry.org/ ↩︎An excellent online database of a huge range of trees giving very good information on each plant - its uses, ecology, identity, propagation, pests etc.
- [3]IUCN Red List of Threatened Species — http://www.iucnredlist.org/ ↩︎A list of plants under threat and facing possible extinction, usually with brief details of the threats and information on habitat.
- [4]Encyclopedia of Tropical Plants - Identification and Cultivation of over 3,000 Tropical Plants — Ahmed Fayaz · Firefly Books Ltd.; New Zealand · 2011 · ISBN 978-1-55407-489 ↩︎A good photograph and terse but detailed information for over 3,000 species of tropical plants. An excellent reference.
- [5]Trees Commonly Cultivated in SE Asia — Jensen. M. · FAO Regional Office, Bangkok. · 1999 · ISBN 974-89377-5-5 ↩︎
- [6]Nuts. — Howes. F. N. · Faber · 1948 · ISBN - ↩︎Rather old but still a masterpiece. Has sections on tropical and temperate plants with edible nuts plus a section on nut plants in Britain. Very readable.
- [7]Cornucopia II — Facciola. S. · Kampong Publications, California. · 1998 · ISBN 0-9628087-2-5 ↩︎The second edition of an excellent guide to the edible uses of plants, though it does not give any details of cultivation etc.
- [8]Tropical and Subtropical Trees - A Worldwide Encyclopaedic Guide. — Barwick. M. · Thames & Hudson, London · 2004 · ISBN 0-500-51181-0 ↩︎A superb book, very concise and well written, giving a wealth of information on 400 or more species including descriptions, habitat, cultivation details and plant uses. A wealth of colour photographs bring each plant vividly to life.