Kiwifruits belong to the genus Actinidia, a group of around 5 to 6 dozen species of climbers in the family Actinidiaceae. They are best known for their edible fruits, although some species are also used as ornamentals, as a source of traditional medicines, and as a stimulant for cats somewhat akin to catnip. The two most commercially important species are A. deliciosa and A. chinensis, both native to China (A. deliciosa grows more in the western, inland, colder areas, whereas A. chinensis grows more in the lowlands in the more eastern provinces towards the coast). Some authors have questioned whether these two taxa should really be treated as distinct species (see Ferguson 2007 and references therein for a discussion of the relationship between these two taxa).
Actinidia deliciosa is a woody vine that may reach 10 m in length. It is dioecious (i.e., individual plants are either male or female). The flowers are white to cream-colored. The fruit is an oval berry (botanically speaking), 55 to 70 mm long, with a light brown skin and green flesh containing many hundreds of tiny black seeds. Although generally grown in warm temperate climates, the species can tolerate a range of conditions. Natural pollen transfer to female plants is sometimes supplemented by spray applications because fruit size is affected by the number of fertilized seeds.
In China, large quantities of kiwifruits are still collected from wild vines. Commercial cultivation of kiwifruit in China started only in the last couple of decades of the 20th century, but by 1998 there were around 45,000 ha of kiwifruit orchards, 75% cultivars of A. deliciosa and 25% cultivars of A, chinensis. Much of the world's commercial stock of A. deliciosa is believed to be derived from stock planted in New Zealand in 1904 (this explains why the common name refers to New Zealand although kiwis are not native there: the name “kiwifruit” was proposed when the fresh fruits were first exported to the United States in 1959 and within a decade had become the accepted name, although in China this fruit is known as "mihoutao", or "monkey peach"). In 1904, Isabel Fraser returned to New Zealand after visiting her missionary sister in China, with kiwifruit seeds. The cultivar 'Hayward', a direct descendant of those first seeds, is now the mainstay of kiwifruit industries throughout the world. (Ferguson 2004, 2007)
The very first commercial kiwifruit orchard was in production by about 1930, but a significant international market for kiwis did not develop until the late 1970s. Kiwis are now grown in Italy, Chile, France, and the United States, among other countries. In 2004, China, Italy, New Zealand, and China accounted for around 80% of the world's commercial kiwifruit production. Today, Italy produces more kiwifruit than any other country with the possible exception of China, and Italy and New Zealand are the largest exporters. The first kiwifruit orchards were established in Italy only 40 years ago, but by 2007 they occupied 26,700 ha and produced 400,000 to 500 000 metric tons of fruit each year. As elsewhere, most Italian kiwifruit plantings are of the cultivar 'Hayward' but there are now orchards of several new cultivars, including yellow-fleshed kiwifruit. The international kiwifruit industry of today, with more than 120,000 ha of orchards planted and with annual production exceeding 1.35 million metric tons of fresh fruit, is based on A. deliciosa and A. chinensis, but a third species, A. arguta, may soon be established as a commercial crop. Most of the Italian kiwifruit crop is consumed within Italy or in other countries of the European Union, whereas most of New Zealand's crop is exported long distances. Ferguson (2007) provided a thorough review of kiwifruit domestication and breeding.
Kiwis contain around 10% total sugars (mainly glucose and fructose) and are rich in vitamin C (most of which remains even after months in storage). Citric acid is the main constituent organic acid.
(Vaughan and Geissler 1997; Huang and Ferguson 2001; Ferguson 2007; Mabberley 2008; Testolin and Ferguson 2009)
Molecular Biology and Genetics
Barcode data: Actinidia deliciosa
Statistics of barcoding coverage: Actinidia deliciosa
Public Records: 1
Specimens with Barcodes: 1
Species With Barcodes: 1
Actinidia deliciosa, Fuzzy Kiwifruit or mangüeyo is a fruiting vine native to southern China, the fruit of which has been declared the national fruit of that country. Other species of Actinidia are also found in China and range east to Japan and north into southeastern Siberia. This species grows naturally at altitudes between 600 and 2,000 m.
Description and ecology
Actinidia deliciosa is a vigorous, woody, twining vine or climbing shrub reaching 9 m.
Its leaves are alternate, long-petioled, deciduous, oval to nearly circular, cordate at the base, and 7.5–12.5 cm long.
Young leaves are coated with red hairs; mature leaves are dark-green and hairless on the upper surface, and downy-white with prominent, light-colored veins beneath.
The flowers are fragrant, dioecious or unisexual, borne singly or in threes in the leaf axils, are five- to six-petalled, white at first, changing to buff-yellow, 2.5–5 cm broad, and both sexes have central tufts of many stamens, though those of the female flowers with no viable pollen. The flowers also lack nectar.
Male and female flowers appear on different plants (dioecious), and both sexes have to be planted in close proximity for fruit set. Bees are normally used by commercial orchards, although the more labour-intensive hand pollination is sometimes employed. Male flowers are gathered and processed to extract their pollen. This is then sprayed back on to the female flowers.
The oblong fruits are up to 6.25 cm long. The russet-brown skin of the fruits is densely covered with short, stiff, brown hairs.
The flesh is firm until fully ripened; it is glistening, juicy and luscious. The color of the flesh is bright-green, or sometimes yellow, brownish or off-white, except for the white, succulent center from which radiate many fine, pale lines.
Varieties and cultivars
The two botanical varieties are:
- Actinidia deliciosa var. chlorocarpa
- Actinidia deliciosa var. deliciosa
Zhong hua (Chinese gooseberry), jing li (northern pear gooseberry), ruan zao (soft date gooseberry) and mao hua (may be tight- or loose-haired) are the four main cultivars of this species in China. 'Abbott', 'Allison', 'Bruno', 'Hayward', Monty ('Montgomery') and 'Greensill' are the most significant cultivars in New Zealand.
Cultivation spread from China in the early 20th century when seeds were introduced to New Zealand by Isabel Fraser, the principal of Wanganui Girls' College, who had been visiting mission schools in China. The seeds were planted in 1906 by a Wanganui nurseryman, Alexander Allison, with the vines first fruiting in 1910.
People who tasted the fruit thought it had a gooseberry flavour, so began to call it the Chinese gooseberry, but being from the Actinidia genus, it is not related to the Grossulariaceae (gooseberry) family.
The familiar cultivar Actinidia deliciosa 'Hayward' was developed by Hayward Wright in Avondale, New Zealand around 1924. This is the most widely grown cultivar in the world. Chinese gooseberry was initially grown in domestic gardens, but commercial planting began in the 1940s.
In 1959, Turners and Growers named it kiwifruit, after New Zealand's national bird, the kiwi—brown and furry.
As of 2006[update], Italy was the leading producer of kiwifruit in the world, followed by New Zealand, Chile, France, Greece, Japan and the United States. Kiwifruit is still produced in its birthplace China, but China has never made it to the top 10 list of kiwifruit-producing countries. In China, it is grown mainly in the mountainous area upstream of the Yangtze River. It is also grown in other areas of China, including Sichuan.
In 2010 and 2011, kiwifruit vines worldwide, in Italy, France and New Zealand, suffered devastating attacks by a bacterial disease caused by Pseudomonas syringae pv. actinidiae, with some of the New Zealand attacks by the virulent strain PSA-V. The disease had first been noticed in Japan in the 1980s, and subsequently in northern Italy (1992) and South Korea.
- Purdue University:Kiwifruit(Actinidia deliciosa)
- "Kiwifruit vine disease by MAF Biosecurity New Zealand".
- Watson, Peter (2011-01-25). "More virulent PSA strain a new worry for kiwifruit growers". The Dominion Post. Retrieved 2011-09-04.
- Fox, Andrea (2011-05-25). "Renewed fears as PSA devastates European orchards". The Dominion Post. Retrieved 2011-09-04.
- Hembry, Owen (2011-08-25). "Relief for kiwifruit industry". The New Zealand Herald. Retrieved 2011-09-04.
The kiwifruit, often shortened to kiwi in many parts of the world, is the edible berry of a cultivar group of the woody vine Actinidia deliciosa and hybrids between this and other species in the genus Actinidia.
The most common cultivars of kiwifruit are oval, about the size of a large hen's egg (5–8 cm / 2–3 in long and 4.5–5.5 cm / 1¾–2 in diameter). It has a fibrous, dull brown-green skin and bright green or golden flesh with rows of tiny, black, edible seeds. The fruit has a soft texture and a unique flavour, and today is a commercial crop in several countries, mainly in Italy, China, and New Zealand.
Also known as the Chinese gooseberry, the fruit was renamed for export marketing reasons in the 1950s; briefly to melonette, and then by New Zealand exporters to kiwifruit. This latter name comes from the kiwi — a brown flightless bird and New Zealand's national symbol, and also a colloquial name for the New Zealand people.
This fruit had a long history before it was commercialised as kiwifruit and therefore had many other older names.
- Macaque peach (獼猴桃 Pinyin: míhóu táo): the most common name
- Macaque pear (獼猴梨 míhóu lí)
- Vine pear (藤梨 téng lí)
- Sunny peach (陽桃 yáng táo), a name originally referring to the Kiwifruit, but often refers to the starfruit
- Wood berry (木子 mù zi)
- Hairy bush fruit (毛木果 máo mù guǒ)
- Unusual fruit or wonder fruit (奇異果 Pinyin: qíyì guǒ, Jyutping: kei4 ji6 gwo2): the most common name in Taiwan and Hong Kong. A quasi-transliteration of "kiwifruit", literally "strange fruit".
Actinidia deliciosa is native to Southern China. Originally known as Yang Tao, it is declared as the "National Fruit" of the People's Republic of China. Other species of Actinidia are also found in India and Japan and north into southeastern Siberia. Cultivation spread from China in the early 20th century, when seeds were introduced to New Zealand by Mary Isabel Fraser, the principal of Wanganui Girls' College, who had been visiting mission schools in Yichang, China. The seeds were planted in 1906 by a Wanganui nurseryman, Alexander Allison, with the vines first fruiting in 1910.
The familiar cultivar Actinidia deliciosa 'Hayward' was developed by Hayward Wright in Avondale, New Zealand around 1924. It was initially grown in domestic gardens, but commercial planting began in the 1940s. Italy is now the leading producer of kiwifruit in the world, followed by New Zealand, Chile, France, Greece, Japan and the United States. In China, kiwifruit was traditionally collected from the wild, but until recently China was not a major producing country. In China, it is grown mainly in the mountainous area upstream of the Yangtze River. It is also grown in other areas of China, including Sichuan.
|This section does not cite any references or sources.|
Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (May 2010)
Almost all kiwifruit in commerce belong to a few cultivars of Actinidia deliciosa: 'Hayward', 'Chico', and 'Saanichton 12'. The fruit of these cultivars are practically indistinguishable from each other and match the description of a standard kiwifruit given at the head of this article.
Gold Kiwifruit or "Hinabelle", with yellow flesh and a sweeter, less acidic flavour resembling a tropical fruit salad, is a new Cultivar Group produced by the New Zealand Crown Research Institute, Plant & Food Research and marketed worldwide in increasing volumes. Some wild vines in India have yellow fruit but are small and not commercially viable. Seeds from these plants were imported to New Zealand in 1987 and the company took 11 years to develop the new fruit through cross-pollination and grafting with green kiwifruit vines. Gold Kiwifruit have a smooth, bronze skin, a pointed cap at one end and distinctive golden yellow flesh with a less tart and more tropical flavour than green kiwifruit. It has a higher market price than green kiwifruit. It is less hairy than the green cultivars, so can be eaten whole after rubbing off the thin, fluffy coat. While the skin of kiwifruit is often removed before serving, it is completely edible.
|Nutritional value per 100 g (3.5 oz)|
|Energy||255 kJ (61 kcal)|
|Dietary fiber||3.0 g|
|- lutein and zeaxanthin||122 μg|
|Thiamine (Vit. B1)||0.027 mg (2%)|
|Riboflavin (Vit. B2)||0.025 mg (2%)|
|Niacin (Vit. B3)||0.341 mg (2%)|
|Vitamin B6||0.63 mg (48%)|
|Folate (Vit. B9)||25 μg (6%)|
|Vitamin C||92.7 mg (155%)|
|Vitamin E||1.5 mg (10%)|
|Vitamin K||40.3 μg (38%)|
|Calcium||34 mg (3%)|
|Iron||0.31 mg (2%)|
|Magnesium||17 mg (5%)|
|Phosphorus||34 mg (5%)|
|Potassium||312 mg (7%)|
|Sodium||3 mg (0%)|
|Zinc||0.14 mg (1%)|
|Manganese 0.098 mg|
|Percentages are relative to US recommendations for adults.|
Source: USDA Nutrient database
Kiwifruit is a rich source of vitamin C, 1.5 times the DRI scale in the US. Its potassium content by weight is slightly less than that of a banana. It also contains vitamin E, and a small amount of vitamin A. The skin is a good source of flavonoid antioxidants. The kiwifruit seed oil contains on average 62% alpha-linolenic acid, an omega-3 fatty acid. Usually a medium size kiwifruit contains about 46 calories, 0.3 g fats, 1 g proteins, 11 g carbohydrates, 75 mg vitamins and 2.6 g dietary fiber.
Raw kiwifruit is also rich in the protein-dissolving enzyme actinidin, (in the same family of thiol proteases as papain), which is commercially useful as a meat tenderizer but can be an allergen for some individuals. Specifically, people allergic to latex, papayas or pineapples are likely to also be allergic to kiwifruit. The fruit also contains calcium oxalate crystals in the form of raphides. Reactions to these chemicals include sweating, tingling and sore mouth; swelling of the lips, tongue and face; rash; vomiting and abdominal pain; and, in the most severe cases, breathing difficulties, wheezing and collapse. The most common symptoms are unpleasant itching and soreness of the mouth, with the most common severe symptom being wheezing. Severe symptoms are most likely to occur in young children.
Actinidin also makes raw kiwifruit unsuitable for use in desserts containing milk or any other dairy products which are not going to be served within hours, because the enzyme soon begins to digest milk proteins. This applies to gelatin-based desserts as well, as the actinidin will dissolve the collagen proteins in gelatin very quickly, either liquifying the dessert, or preventing it from solidifying. However, the U.S. Department of Agriculture suggests that cooking the fruit for a few minutes before adding it to the gelatin will overcome this effect. Sliced kiwifruit has long been regularly used as a garnish atop whipped cream on New Zealand's national dessert, the pavlova. It can also be used in curry.
Kiwifruit also serves as a natural blood thinner. A recent study performed at the University of Oslo in Norway reveals that—similar to popular mainstream aspirin therapy—consuming two to three kiwifruit daily for 28 days significantly thins the blood, reducing the risk of clots, and lowers fat in the blood that can cause blockages.
The kiwifruit skin is edible and contains high amounts of dietary fiber. In a fully matured kiwifruit one study showed that this as much as tripled the fiber content of the fruit. In addition, as many of the vitamins are stored immediately under the skin, leaving the skin intact greatly increases the vitamin c consumed by eating a single piece of kiwifruit when compared to eating it peeled. As with all fruit, it is recommended that if eating the skin, the fruit be washed prior to consumption.
UN Food and Agriculture Organization (FAO)
Kiwifruit can be grown in most temperate climates with adequate summer heat. Where Actinidia deliciosa is not hardy, other species can be grown as substitutes.
Kiwifruit is commercially grown on sturdy support structures, as it can produce several tonnes per hectare, more than the rather weak vines can support. These are generally equipped with a watering system for irrigation and frost protection in the spring.
Kiwifruit vines require vigorous pruning, similar to that of grapevines. Fruit is borne on one-year-old and older canes, but production declines as each cane ages. Canes should be pruned off and replaced after their third year.
The plants are normally dioecious, meaning that individual plants are male or female. Only female plants bear fruit, and only when pollenized by a male plant. One male pollenizer is required for each three to eight female vines. An exception is the cultivar 'Issai', a hybrid (Actinidia arguta x polygama) from Japan, which produces perfect flowers and can self-pollinate; unfortunately it lacks vigour, is less hardy than most A. arguta forms and is not a large producer.
Kiwifruit is notoriously difficult to pollinate because the flowers are not very attractive to bees. Some producers blow collected pollen over the female flowers. But generally the most successful approach is saturation pollination, where the bee populations are made so large (by placing hives in the orchards) that bees are forced to use this flower because of intense competition for all flowers within flight distance.
- ^ Green, Emily. "Kiwi, Act II". Los Angeles Times. http://articles.latimes.com/2002/may/08/food/fo-kiwi8.
- ^ 李, 时珍. "本草纲目·果部". http://zh.wikisource.org/wiki/%E6%9C%AC%E8%8D%89%E7%B6%B1%E7%9B%AE/%E6%9E%9C%E9%83%A8. Retrieved 2007-05-07.
- ^ "Kiwifruit". WHFoods. http://www.whfoods.com/genpage.php?tname=foodspice&dbid=41. Retrieved 2009-12-06.
- ^ "National Symbols of China". 123independenceday.com. http://www.123independenceday.com/china/national-symbols.html. Retrieved 2009-12-06.
- ^ Isabel Fraser - Hand carried the first kiwifruit seeds from China
- ^ Kiwifruit planting and production in China
- ^ Kiwifruit in China
- ^ a b "Fruits & Veggies More Matters » Kiwifruit: Nutrition . Selection . Storage". Fruitsandveggiesmorematters.org. http://www.fruitsandveggiesmorematters.org/?page_id=180. Retrieved 2009-12-06.
- ^ "Kiwi Fruit Nutrition Facts". Nutrientfacts.com. http://www.nutrientfacts.com/foodpages/nutritionfacts/nutritionfacts_kiwi_fruit.htm. Retrieved 2009-12-06.
- ^ Seed Oil Fatty Acids - SOFA Database Retrieval
- ^ NutritionData on Kiwifruit
- ^ Rush et al. (2002-06). "Kiwifruit promotes laxation in the elderly". Asia Pacific Journal of Clinical Nutrition. http://www.blackwell-synergy.com/links/doi/10.1046/j.1440-6047.2002.00287.x. Retrieved 2007-06-11.
- ^ USDA Agricultural Marketing Service (1994-01). "How To Buy Fresh Fruits". United States Department of Agriculture . http://www.ams.usda.gov/howtobuy/ffruits.pdf. Retrieved 2006-12-02.
- ^ http://zespri.com/zespri-recipes/mains/korma-kiwi-curry.html
- ^ "Natural blood thinner | Better Nutrition | Find Articles at BNET.com". Findarticles.com. 2009-06-02. http://findarticles.com/p/articles/mi_m0FKA/is_12_66/ai_n7586524. Retrieved 2009-12-06.
- ^ Sommerburg O, Keunen JE, Bird AC, van Kuijk FJ. Fruits and vegetables that are sources for lutein and zeaxanthin: the macular pigment in human eyes. Br J Ophthalmol . 1998;82:907-910.
- ^ http://faostat.fao.org/faostat/form?collection=Production.Crops.Primary&Domain=Production&servlet=1&hasbulk=0&version=ext&language=EN
Names and Taxonomy
Comparison of <i>A. deliciosa</i> and <i>A. chinensis</i>
In older classifications, A. deliciosa was considered a variety of A. chinensis, but since the 1980s, the two species have split based on characteristics including fruit shape, skin texture, and hairiness. In general, A. deliciosa is more oblong and cylindrical, while A. chinensis is rounder and more globe-shaped. A. deliciosa has a thicker skin covered with more and stouter hairs, while A. chinensis has a smoother, thinner skin, with hairs more like peach fuzz, which can be rubbed off easily. A. deliciosa is the source of the widely produced “Hayward” cultivar synonymous with kiwifruit, but cultivars of A. chinensis were developed starting in 1977 with commercial production starting in the 1990s; the fruit is marketed as “gold kiwifruit.”
(Beutel 1990, FAO/Ecocrop 2012, Ferguson 1999, Mainland and Fisk 2006, Morton 1987, van Wyk 2005.)
To request an improvement, please leave a comment on the page. Thank you!