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Department of Agronomy
Wageningen Agricultural University
Wageningen, The Netherlands
[Dimitri Jacobs, a final year undergraduate student at Wageningen, spent the practical period of his training from May to September 1997 at the New Crops Program, University of Queensland Gatton College.
At the same time, a list of forty species was compiled by the organisers of a Tropical Fruit and Nut Planning Workshop sponsored by RIRDC in Cairns in July 1997 (featured in the Australian New Crops Newsletter #8: 12-17).
From this list, Dimitri identified pitaya fresh fruit as worthy of further investigation as a potential commercial product.
Part of the period spent by Dimitri at Gatton was dedicated to a literature review and an evaluation of pitaya in Australia, with the cooperation of officers from WANATCA, the Department of Primary Industry and Fisheries Northern Territory (DPIFNT) and the Ben Gurion University, Israel along with growers in Australia.
The preliminary search on pitaya, by means of the numbers of published papers worldwide indicated it was among the crops receiving recent attention in the literature.
Such attention appears to be limited to its appearance in foreign literature and the presence of the crop in developing countries.
Recent research carried out in Israel towards drought resistant crops for the Negev Desert has drawn attention to this whole cactus grouping (Australian New Crops Newsletter #3: 6).
The following article has been extracted from articles appearing in:
* The Exotics (Rare Fruit Council of Australia, March-April 1998; Telephone: 07 4788 8328) and
* WANATCA (West Australian Nut and Tree Crop Association Inc; Telephone: 08 9388 1965) Yearbook 22, as well as
* the Report written by Dimitri of his experiences at Gatton.]
Pitaya is a common name applied to a broad variety of warm-climate cacti fruit (Table), from different species and genera. It represents an interesting group of under-exploited crops with potential for human consumption.
Various types of columnar and climbing cacti bear the fruit referred to as pitaya.
Distribution of the Hylocereus and Selenicereus species occurs roughly from Mexico and Texas to Peru and Argentina. Hylocereus species have been commercially grown in the Americas and in Vietnam.
They were imported into the latter country by the French and are locally recognised as native species. Much of the recent research and development of pitaya has occurred in Israel.
The species Hylocereus guatemalensis was probably originally grown in Australia at the Queensland Department of Primary Industries' Horticultural Research Station at Kamerunga near Cairns.
A yellow fruiting species originating from Kamerunga is currently being grown by the DPIFNT.
Early imports into North Queensland from Colombia are recorded as Hylocereus ocampensis (red pitaya) and Cereus triangularis (yellow pitaya).
The yellow pitaya was probably Selenicereus megalanthus, and the red pitaya, Hylocereus ocamponis or Hylocereus undatus. Cereus triangularis is a synonym of Hylocereus undatus (Table).
The pitaya is a species of dry tropical climates. Rainfall requirements are modest (600-1300 mm) and excessive rain leads to flower drop and fruit rot. Maximum temperatures of 38-40 C and minor short frosts cause little damage.
Pitaya fruit is produced on segmented, vine-like crawling cacti. These plants have aerial roots and originally exist as epiphytes, the roots being used to attach themselves to supports. The aerial roots find nutrients in cracks where organic material concentrates.
Hence, there is a positive response in growth to the amount of organic matter in the soil. However, high numbers of roots and buds have been obtained from culture in sand.
Cultural practices employ a trellis, or, traditionally, old tree stumps or living tree posts.
As the plants have a high tolerance to sulphurous gases, commercial production in Nicaragua is found on the slopes of the Mount Santiago volcano.
In Nicaraguan plantings, propagation is done by stem cuttings, placed at 3 x 5 m spacings on living tree posts. Nutrients are applied by foliar spraying or through fertiliser spreading.
The plants are claimed to be shade tolerant yet bleaching and death can occur at high levels of light intensity in Selenicereus megalanthus. Shading has been used in Israel.
Pitaya flowers at night. The large white flowers render them popular as ornamentals, being referred to as Moonflower, Lady of the Night or Queen of the Night.
Many species of pitaya are self-sterile so moths and bats are required to achieve cross pollination.
The period during which individual flowers are open is usually one night only so effective pollinating agents are essential.
Ants have been observed pollinating flowers and honey bees do visit the flowers, but each of these is relatively inefficient at achieving pollination and fruit set.
Fruits are brightly coloured and are unique in appearance.
The red pitaya bears large pink, red or mauve fruits. Each weighs around 150-600g and contains many, small edible seeds.
The pulp varies from white to various shades of red.
The yellow pitaya (Selenicereus megalanthus) has a smaller fruit with white pulp and higher sugar levels than the red pitaya.
The fruit is covered with many small clusters of spines, which can be brushed off the fully ripe fruit. It is commercially grown in Colombia.
Fruit is harvested when changing colour and can hold for at least a week. Cooling (10-12 C) does not seem to affect the fruit adversely.
Fruit set occurs 30-50 days after flowering and 5-6 fruit crop cycles (between May and November) a year are achievable in Nicaragua, yielding 10-12 t/ha in the fifth year of production. Orchards of the same species yield 30 t fruit/ha/year in Vietnam.
Some pests and diseases have been recorded on pitaya.
Problems in Australia are most likely to involve birds, possums, rats or bats feeding on the fruit. Observations in Australia have indicated similar effects to those caused in Central America by the bacterium Xanthomonas campestris, causing rot in the stem flesh, leaving the main veins intact. As well as local insect attack, the fungus Dothiorella, causes brown spots on the fruit in Nicaragua.
Hylocereus has also become popular in ornamental production in greenhouses in Europe and the United States as rootstock for other, slower growing ornamental cacti.
Freshly cut stems and flowers of Selenicereus grandiflorus, in particular, are used in the preparation of drugs which have a spasmolytic effect on the coronary vessels and promote blood circulation. For this purpose, cuttings are cultivated in hot-houses.
Selenicereus megalanthus contains the heart tonic captine.
Hylocereus undatus fruit has been used to combat anaemia.
Some pitaya germplasm is already present in Australia, distributed among growers in the Northern Territory and in Queensland.
Experience in growing this crop in Australia has so far indicated low yields.
Two fruiting cycles, one in May, and a smaller one in August, have been recorded in the Brisbane area.
In northern Australia, there are apparently difficulties with fruit set.
Limited production in California by a few producers has led to pitaya being occasionally sold at Farmers' Markets.
One species is grown in Vietnam. Pitayas are commercially produced and sold as dragon fruit, dragon pearl fruit or thang loy. Production takes place along the coast from Nga Trang to Ho Chi Ming City.
Although considerable investment would appear to be necessary to establish commercial production of pitaya, Israeli experience indicates that relatively cheap trellising is sufficient. However, shade may also be necessary and could assist with reducing bird attack.
Rare, attractive fruits will always attract attention in the market place.
Customer demand is currently fragile because the fruit is unknown. The market size for exotic fruit is relatively limited, but growing.
Consumer acceptance, measured in the Brisbane market, has been good for yellow pitaya but only moderate for red pitaya, as fresh fruit. The musky smell and taste of the red variety may explain its apparently reduced appeal in this market.
In August 1998, market prices in Barcelona of $7-8 per kg and $40 per 8-12 pieces were observed. Local Californian produce was sold at $8-10/ kg throughout 1996. Utopia Pty Ltd is successfully importing Colombian pitayas into Europe.
Vietnamese exports to other Asian markets show potential exists for expansion into Hong Kong, China and Japan with high quality fruit. Twenty two tons of pitaya were imported into Japan in 1988. Specimens of the Vietnamese fruit have been imported into the Northern Territory.
The variability in size, taste and colour of pitaya fruit indicates the strong need for co-ordination in commercialisation.
For future export, attention towards the Vietnamese Hylocereus undatus varieties and the varieties being developed in Israel would appear to be warranted.
Pitaya fruit is usually harvested once the season for most Australian tropical fruits is finished. The fruits are easier to handle than prickly pear fruit, since the skin is thornless or thorns are easily removed. The small black seeds are similar to the seeds of the kiwi fruit.
Profitability is expected to be high in the first phase of development of the pitaya in northern Australia. This attractive and unique fruit fits into the Australian market, and the fruit industry in northern Australia is well established for the introduction of new product.
There is an increasing trend in demand for tropical fruit at present and prices are high. Additionally, high quality produce could be exported to those countries in Asia where the fruit is already known.
One major weakness is the lack of any experience with pitaya in Australian markets. There are no major commercial growers or plantings as yet. Consumer awareness will require promotion and education over time before the product is readily identifiable in the market place.
Lack of resources is a common constraint in such a situation, requiring good communication between those already interested in the commercialisation of pitaya. Prices are likely to fall if higher production levels are obtained. To succeed in providing future export markets, identification and co-ordination between growers and industry are likely to be keys to success.
The genera and species present under the single name of pitaya is likely to cause difficulties for consumers in recognising of the product. Brand names probably should be applied to differentiate products.
Better varieties and a range of production research in Israel create opportunities for commercialising pitaya in Australia. The importation and/or licensing of germplasm for evaluation are options.
Pitaya has a relatively quick return, for tropical fruits, since it can begin bearing in its second year, reaching full production in five years.
Low inputs of water and fertiliser and the appropriate management of pests and diseases could render organic production a possibility but to maintain high prices and demand in new exotic fruits, high quality is essential.
Quarantine requirements to import plant material from overseas and the phytosanitary regulations controlling the export of fruits to Asian markets would require close examination.
Relatively cheaper commercial production in Vietnam and some South American countries may reduce the competitive advantage for Australian producers on the export market.
Pitaya can act as a host for fruit fly, but apparently Japanese Plant Quarantine can provide certificates if proper disinfestation has been undertaken.
Industrial processing of the red pitaya fruit, for ice-cream, juice, wine, fruit salads and other recipes warrants further research. A restaurant supplier in Brisbane has shown some interest in the process and preparation of pitaya.
Consumer analysis and education, as with all new fruit products is essential.
Research on the environmental factors which influence the induction of buds in pitaya would be useful for the understanding of variability in fruit set between seasons, between varieties and between sites. Flowering is initiated at the end of the dry season in Central America and continues throughout the wet season.
Barbeau (G Barbeau (1990) La pitaya rouge, un nouveau fruit exotique. Fruits 45: 141-7; translated into English and published in WANATCA Yearbook 17: 74-80) believes flowering in pitaya is a response to daylength. Fruiting of pitaya in Israel occurred in two or three waves from June to November, and was believed to possibly be temperature related.
Studies in Israel of the cytogenetic make-up of Selenicereus megalanthus are hoping to explain the low seed set and poor fruit weight of this species.
Cross pollination between Hylocereus species has yielded heavier fruit.
Molecular studies are currently also being conducted in Israel to understand the taxonomic relationships between the pitayas.
Crop improvement in Cereus peruvianus, is also proceeding with a view to the production of pitaya-like fruit on columnar cactus plants, which would not require the supporting trellises that are needed for most of the crawling cacti.
Disinfection measures and other postharvest treatments are required if pitaya should be exported from Australia to Asian markets.
Potential growers of pitaya should define the market and product themselves and prepare an appropriate business plan, with professional assistance, according to the specified target. There are many plants from the tropical and subtropical areas of the Americas which have been cultivated, but have never become well known.
This resource in semi-arid crops is likely to be a promising resource for relatively dry regions in the future. CAM plants and species from arid zones should also get more attention if present trends continue.
As a footnote:
Australians having some knowledge of the problems created by prickly pear (Opuntia vulgaris) in Queensland prior to the introduction of the Cactoblastis beetle can appreciate the risks involved in attempting to domesticate some of the cacti species and develop new crop industries from them.
In the desert areas where cacti are being developed in Israel, Professor Mizrahi indicates there is no likelihood of the uncontrolled spread of such species.
Any claims made by authors in the Australian New Crops Newsletter are presented by the Editors in good faith. Readers would be wise to critically examine the circumstances associated with any claims to determine the applicability of such claims to their specific set of circumstances. This material can be reproduced, with the provision that the source and the author (or editors, if applicable) are acknowledged and the use is for information or educational purposes. Contact with the original author is probably wise since the material may require updating or amendment if used in other publications. Material sourced from the Australian New Crops Newsletter cannot be used out of context or for commercial purposes not related to its original purpose in the newsletter
Contact: Dr Rob Fletcher, School of Land and Food, The University of Queensland Gatton College, 4345; Telephone: 07 5460 1311 or 07 5460 1301; Facsimile: 07 5460 1112; International facsimile: 61 7 5460 1112; Email:firstname.lastname@example.org
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originally created by:GK; latest update 6 June 1999 by: RF