MELALEUCA CAJUPUTI: CHARACTERISTICS, HABITAT, USES, PESTS - BIOLOGY - 2025

Melaleuca cajuputi is a woody plant that belongs to the Myrtaceae family. It is an evergreen tree with an erect trunk that can reach up to 30 m in height in the oldest individuals.

It is a native species of Australia and colonizes the swamp forests of this and other countries in the region of Oceania and South Asia. Its common name is the cajuput or melaleuca tree, and it is an evergreen plant that has alternate leaves.

Melaleuca cajuputi. R. Purdie

From the point of view of its applications, M. cajuputi is a tree that is used to control various pests in crops. This is because this plant produces metabolites with antibiotic properties.

However, Melaleuca cajuputi is attacked by multiple pests, among which the attack by Puccinia spp. It is also a plant susceptible to some species of termites.

characteristics

M. cajuputi trees have an average height of between 15 and 25 meters. The young trees of this plant show an excurrent-type crown pattern, with a guide bud. If this yolk becomes damaged, it is replaced by another. Thus, older trees show a pattern of multiple main stems.

Melaleuca cajuputi seedlings develop adventitious roots that connect to the portion of the stem that is above the ground. Since M. cajuputi tends to colonize flooded areas, the roots of this plant show a high percentage of aerenchyma. This somehow explains the tolerance of this plant to flooding.

Melaleuca leaves can be 45 to 140 mm long and 15 to 50 mm wide. In turn, the petioles are between 5 and 15 mm long. The leaves have long dense hairs that are narrowly elliptical in shape.

Melaleuca cajuputi. Elisabeth duisdeiker

The inflorescence of M. cajuputi is a spike up to 28 mm wide, with pubescent rachis. The hypanthus is pubescent, cup-shaped, 1.5 to 1.7 mm long and 1.7 to 2.5 mm wide.

On the other hand, the petals are 2.3 to 2.5 mm long, with circular or linear glands. The stamens can be 1.1 to 3.5 mm long and there may be eight to thirteen stamens per bundle, filamentous in shape, with cream coloration.

Melaleuca flowering can occur throughout the year. However, there are studies that show that the flower production of this plant begins between October and November, with a maximum flowering in December.

After flowering, fruits develop in the form of capsules, which can contain approximately 264 seeds.

Inflorescence of Melaleuca cajuputi. Murray fagg

Habitat and description

Weather

M. cajuputi trees require a warm climate, but are nonetheless tolerant of freezing.

The westernmost area where the Melaleuca cajuputi can be found has a climate that is characterized by being rainy and with mild winters. The coldest month has a temperature above 0 ° C and below 18 ° C.

The hottest month has temperatures above 22 ° C; and the constant humidity conditions in the driest month are due to rainfall of at least 60 mm.

Substratum

Melaleuca cajuputi trees are well adapted to flooded, well-drained and saturated soils. Generally, the soils in which M. cajuputi grows are found in the suborders Psammaquents, Aquods, and Saprists of the orders Entisol, Spodosol, and Histosol, respectively.

Furthermore, M. cajuputi establishes well in acid sands, organic soils and limestone of varying thickness. To establish themselves, the seeds require contact with a constant supply of water. However, they can also do so in mineral and organic soils.

Melaleuca cajuputi plants can tolerate high salinity conditions. In turn, they can also tolerate a pH range of 4.4 to 8.0. Seedlings, on the other hand, grow poorly in soils with a low concentration of nutrients. For this reason the roots of this plant tend to cover a lot of land.

Distribution

Melaleuca cajuputi is distributed from Indonesia (southeast of Irian Jaya), Papua New Guinea (southeast of Papua), and Australia (northeast of Queensland).

The ecological units that M. cajuputi tends to colonize are lowland flooded forests, open forests, echo tone between swampy monsoon forests and savannas, and riparian banks adjacent to a rain forest, among others.

Distribution of Melaleuca cajuputi. Pancrat

Applications

Melaleuca cajuputi flowers are a good source of nectar and pollen for local bees (Apis dorsata and Apis florea) and other insects, so honey producers tend to keep bees near the cajeput tree forests..

The forests of M. cajuputi provide the local population with many products such as wood for fuel and for building materials.

The essential oils extracted from the cajeput have multiple medicinal properties, which is why this plant is part of the traditional medicine of the regions of Oceania and South Asia.

Furthermore, cajeput essential oils are widely used in the cosmetics and perfume industry. Thus, worldwide a 50 ml bottle is priced around 3 euros.

From an environmental point of view, Melaleuca cajuputi trees help regulate water and climate, maintain relatively acidic soils, and also provide a refuge for wildlife.

Plagues and diseases

The natural enemies of M. cajuputi are insects, mainly weevils and termites. The Oxyops vitiosa weevil feeds on the tips of growing stems, which leads to a decrease in growth and an interruption of flowering.

Likewise, the larvae of the piralid Poliopaschia lithochlora also cause damage to M. cajuputi plants. For their part, termites also cause severe damage to the stem structure of M. cajuputi.

The biotrophic fungus Puccinia spp causes severe damage to the leaf tissue of Melaleuca cajuputi, leading in some very extreme cases to the complete death of an adult individual. Young individuals are the most susceptible to this pest, especially in stressful environmental conditions.

References

1. Carrick, J., Chorney, K. 1979. A review of Melaleuca L. (Myrtaceae) in South Australia. Journal of the Adelaide Botanic Garden. 1 (5): 281-319.
2. Craven, LA, Barlow, BA 1997. New taxa and new combinations in Melaleuca (Myrtaceae). Novon. 7: 113-119.
3. Miwa, M., Tanaka, R., Shinone, M., Kojima, K., Hogetsu, T. 2000. Develoment of polymorphic microsatellite markers in tropical tree species, Melaleuca cajuputi. Molecular ecology. 9: 629-644.
4. Serbesoff-King, K. 2003. Melaleuca in Florida: a literature review on the taxonomy, distribution, biology, ecology, economic importance and control measures. J. Aquat. Plant Manage. 41: 98-112.
5. Tanaka, K., Masumori, M., Yamanoshita, T., Tange, T., 2011. Morphological and anatomical change of Melaleuca cajuputi under submergence. Trees. 25: 295-704.
6. Tang, NQ 2007. Pollination ecology of Melaleuca cajuputi, Nypa fructicans and the Flower visitors. Journal of Apicultural Research. 47 (1): 10-16.