Iris tenuifolia

Iris tenuifolia is a beardless iris in the genus Iris, in the subgenus Limniris and in the series Tenuifoliae of the genus. It is a rhizomatous herbaceous perennial, from a wide region over central Asia, including Afghanistan, Pakistan, (the former Soviet Union republics of); Kazakhstan, Uzbekistan and Mongolia and in China. It has long greyish-green leaves, short stem and pale violet, lilac, pale blue, or purple flowers.

Iris tenuifolia
Flower head of Iris tenuifolia in Kazakhstan
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Monocots
Order:	Asparagales
Family:	Iridaceae
Genus:	Iris
Subgenus:	Iris subg. Limniris
Section:	Iris sect. Limniris
Series:	Iris ser. Tenuifoliae
Species:	I. tenuifolia
Binomial name
Iris tenuifolia Pall
Synonyms[1]
Cryptobasis tenuifolia (Pall.) Nevski Iris acaulis Pall. Iris regelii Maxim. ex Regel Joniris tenuifolia (Pall.) Klatt Neubeckia tenuifolia (Pall.) Alef. Xiphion tenuifolium (Pall.) Schrank

Description

Iris tenuifolia is very similar in form to the Mediterranean Iris unguicularis. As they both have very small stems and the seed capsules are often hidden within the leaves of the plant.[2]

It has a dark brown, thin, short, knobbly, tough, wood-like rhizomes.[3][4][5] Underneath, it has a network of fibrous roots.[6] On top of the rhizome, at the base of the leaves, are the brown or red-brown, fibrous remains of the previous seasons leaves. Which act as sheaths, for the new leaves.[3][5][7] The sheaths can be up to 6–20 cm (2–8 in) long.[6][5]

It can be either a single plant or can grow into thick clumps of plants.[5][8]

It has greyish-green, linear, twisted, leaves, that can grow between 20–60 cm (8–24 in) long and 1.5–2 mm wide.[7][9][10] They do not have a mid-vein but parallel veins,[3][4][6] and are acuminate (ending in a point).[5] They continue to grow after blooming, and can end up as a mass of twisted leaves.[11]

The leaves are longer than the flowering stems.[5]

It has a very short flowering stem or scape, 10–30 cm (4–12 in) long.[12][13][14] Although, sometimes the stems do not emerge above ground.[3]

It has 2 to 4, pointed (acuminate), membranous, green, between 5–10 cm (2–4 in) long and 8–10 mm wide, spathes (leaves of the flower bud).[3][6][7]

The stems hold normally 1–3, terminal (top of stem) flowers,[7][9][15] blooming in spring, between April and May,[3][6][13] or late as early June (in Russia).[10]

The scented flowers,[5] are 4–7 cm (2–3 in) in diameter,[7] and come in shades of pale violet,[3][14] lilac,[5][15][14] pale blue,[9][15][13] or purple.[4][10][13] It has 2 pairs of petals, 3 large sepals (outer petals), known as the 'falls' and 3 inner, smaller petals (or tepals, known as the 'standards'.[16] The falls are spatulate (spoon shaped) or obovate-lanceolate,[4][6] 4.5–6 cm (2–2 in) long and 1.5 cm (1 in) wide.[3][6][7] They have a thin central yellow crest or mid-vein, dark veins (on a pale colour), and a band of papillose (or small hairs).[3][5][14] The narrower, oblanceolate, erect standards are 5 cm (2 in) long and 5–9 mm wide.[3][4][6]

It has a long, slender thread-like, perianth tube, 4.5–8 cm (2–3 in) long.[3][5][7]

It has 3 single coloured, style branches, 4 cm (2 in) long and 4–5 mm wide.[3] They attenuate (narrow slightly) and at the tips, are toothed.[4][6][5]

It has a slender 3–4 mm long pedicel,[5] 3 cm (1 in) long Stamens and a cylindric 7–12 cm (3–5 in) long and 2 mm wide, ovary.[3]

After the iris has flowered, between late July and early August (in Russia),[10] or between August and September (in China). It produces an ovoid or sub-globose, 3.2–4.5 cm (1–2 in) long and 1.2–1.8 cm (0–1 in) wide, seed capsule. It has short beak-like appendage on the top.[3][4][6]

The seeds are oval (or turbinate – like a top) shaped, wrinkled and black-brown to brown.[6][5][10]

Often, the seed capsule is hidden by the long leaves.[2]

Biochemistry

In February 1997, a study was published in which 6 new flavanones, isolated from the rhizomes of Iris tenuifolia, using high resolution mass spectrometry.[17]

In 2005, it was noted that the rhizomes of Iris tenuifolia are the source of the largest number of new 2’-O-substituted simple flavanones within a single species.[18]

Between 2007 and 2011, a study was carried out on chemical constituents and pharmacological activities of Iris tenuifolia and Iris halophila. Using chromatographic and spectroscopic techniques. The irises have been used in various tradition herbal remedy's, such as traditional Mongolian herb medicine and Uighur herb medicine.[19]

In 2008, several chemical compounds were extracted from Iris tenuifolia. These included; 'izalpinin', 'alpinone', 'arborinone', 'irilin B', 'irisone A', 'irisone B', 'betavulgarin', 'beta-sitosterol' '5,7-dihydroxy-2', '6-dimethoxy-isoflavone' , 2',5-dihdroxy-6,7-methylenedioxy flavanone, 'irisoid A' and 'ethyl-beta-d-glucopyranoside'. Also 2 new compounds were found, tenuifodione and tenuifone. All found using spectroscopic methods.[20]

In 2011, 2 flavans and a flavanone, were extracted from the rhizomes of Iris tenuifolia and then tested against stem cells.[21]

In 2012, a genetic study was carried out on Iris laevigata and several of its closely related iris species, including Iris ensata, Iris setosa, Iris halophila, Iris scariosa, Iris potaninii, Iris tenuifolia, Iris bloudowii, and Iris sanguinea.[22]

In 2014, the characteristics of phenotypic plasticity and ecological adaptation of Iris tenuifolia from various habitats in Xinjiang, China, were studied.[23]

As most irises are diploid, having two sets of chromosomes. This can be used to identify hybrids and classification of groupings.[16] It has a chromosome count: 2n=14.[3][24]

Taxonomy

It is written as 细叶鸢尾 in Chinese script and known as xi ye yuan wei in Pinyin Chinese.[3][4][25]

The Latin specific epithet tenuifolia comes from the almagamtion of two Latin words tenuis meaning 'fine or thin' and folia mean leaf.[26]

It has the common names of Egeria Iris.[27][27][28] Note; 'Egeria' means water buffaloes or cows pulling (in China).[4] Another common name is narrow leafed iris,[29] or fine leaved iris,[30] or slender-leaf iris,[25] or silk leaves Iris.[4][27]

It was published and described by Peter Simon Pallas in Reise Russ. Reich. Vol.3 on page 714 in 1776.[31]

It was introduced to Russia in 1812, and was noted as growing in the front garden of Mr. A. Razumovsky near Moscow.[30]

It was later published with an illustration in The Gardeners' Chronicle 3rd. Series Vol.59 on page 196 on 8 April 1916.[32]

It was verified by United States Department of Agriculture Agricultural Research Service on 2 October 2014,[25] then as of January 2015, it is listed as a tentatively accepted name by the RHS.[33]

Distribution and habitat

Iris tenuifolia on the left bank of Syr-Darya river in Kazakhstan

Iris tenuifolia is native to a wide region, of various temperate areas of Central Asia.[25][33] Which extends from the Volga through Turkestan into Mongolia,[12] and China.

Range

It is found in the western Asian countries of Afghanistan and Pakistan.[3][6][25]

Also in the middle Asian countries of (the former Soviet Union republics of); Kazakhstan, Uzbekistan and Mongolia.[3][14][25] Also found in regions of Russia, including Agin-Buryat Okrug, Bashkortostan, Chelyabinsk, Chita and Siberia.[13][14][25] It is listed with Iris bloudowii, Iris humilis, Iris ruthenica, Iris sibirica and Iris tigridia as being found in the Altai-Sayan region (where Russia, China, Mongolia and Kazakhstan come together).[34]

It is found within central China,[9][10][14] in the provinces of Gansu, Hebei, Heilongjiang, Jilin, Liaoning, Nei Mongol, Ningxia, Qinghai, (Shandong[3]), Shanxi, Xinjiang and Xizang.[3][4][25]

One reference mentions Turkey,[6] another reference mentions Iran.[11] Since most others do not mention these countries, they are not regarded as valid.

Habitat

It is grown in semi-desert, desert or mild mountainous areas.[15]

On sandy steppes, on dunes, beside sandy riverine grasslands or river banks, on dry coastal sand regions, on gravelly desert-like slopes and in the crevices of rocks.[8][10][15]

It is also grown at altitudes of 1000 to 4200m above sea level.[6][8][13]

In north east China, it is found growing on poor soils on open tree-less plains.[11]

Conservation

In 2003, it was listed as an endemic vascular species of the temperate steppe region of Inner Mongolia, China, along with Stipa grandis, Artemisia frigida, Festuca ovina, Thymus serpyllum, Caragana microphylla, Koeleria cristata and others.[35]

It is included in the IUCN 'Red Data Book' of the Chita Oblast of 2002, listed as 'rare'. It is now protected in Dauria and Khopyor reserves.[30]

Cultivation

Iris tenuifolia is rare in cultivation in the UK.[9][36] It is rare in cultivation in the US as well.[11]

They are more grown by specialised collectors or for scientific and research purposes.[6][11]

It was sometimes used as annual plant and only planted during the summer (in the UK, in 1800s).[36]

It is hardy, if sited in a northern continental climate. Similar to Nebraska, North Dakota or South Dakota.[11] It is hardy in parts of Russia. It has been grown in Moscow, St Petersburg and Chita.[10]

It prefers sandy or sandy loam soils, similar to the desert habitat.[6][9][15] It prefers alkaline soils.[8]

They prefer positions in full sun.[8]

It needs to be kept dry during winter, needing the protection of bulb frames (in the UK). It only needs water during the growing period.[9] The plant loses its foliage during the winter, as it is removed by the forces of wind, snow and other bad weather conditions. It then re-grows leaves, in April and May.[11]

It has high drought and heat tolerance (desert-like conditions).[8][11][15]

Propagation

The seed of Iris tenuifolia is rarely used by western horticulturists, as the plants rarely flower.[11] William Rickatson Dykes notes that it made no satisfactory growth and never flowered.[2]

In other flowering regions, the seed can be harvested in autumn, washed, fresh or dried.[6]

Hybrids and cultivars

Due to its high drought and heat resistance, it could be useful in breeding purposes.[10][30]

Uses

In 2001, a study was carried to monitor the effects of the iris, within a herbal remedy for kidney protection was carried out.[29]

The Iris genus has been used as a traditional folk medicine, used to treat a variety of diseases, such as cancer, inflammation, bacterial and viral infections.[37] It was found that compounds isolated from Iris germanica have anti-tumor, anti-oxidation, anti-malarial parasite and anti-TB and other positive effects.[38]

The roots, seeds and flowers of the iris, are used as ingredients in herbal medicines. They have been used as tocolysis (also called anti-contraction medications or labor represents) and to treat fetal metrorrhagia.[6]

On 24 December 2009, a patent was granted, for the extraction of Iris tenuifolia. Due to its chemical compounds being used in the treatment of Alzheimer's disease.[37]

References

1. "Iris tenuifolia Pall. is an accepted name". theplantlist.org (The Plant List). 23 March 2012. Retrieved 19 January 2015.
2. Dykes, William. "Dykes on Iris" (PDF). beardlessiris.org (The Group for Beardless Irises). Retrieved 21 November 2014.
3. "FOC Vol. 24 Page 305". efloras.org (Flora of China). Retrieved 28 January 2015.
4. "中国豆科植物在线 (chinese name)". fabaceae.onlineflora.cn. Retrieved 19 January 2015.
5. Komarov, V.L. (1935). "Akademiya Nauk SSSR (FLORA of the U.S.S.R.) Vol. IV". Retrieved 9 October 2014.
6. "Egeria Iris". tl.swewe.net. Retrieved 29 January 2015.
7. James Cullen, Sabina G. Knees, H. Suzanne Cubey (Editors) The European Garden Flora Flowering Plants: A Manual for the Identification(2011) , p. 259, at Google Books
8. "Subgenus Tenuifolia (Tenuifolia) – fine-leaved iris". flower-iris.ru. Retrieved 29 January 2015.
9. Cassidy, George E.; Linnegar, Sidney (1987). Growing Irises (Revised ed.). Bromley: Christopher Helm. p. 139. ISBN 978-0-88192-089-5.
10. "Subgenus Tenuifolia (Tenuifolia) – fine-leaved irises". flower.onego.ru. Retrieved 22 January 2015.
11. Murrain, Jim (3 June 2010). "Subject: Iris tenuifolia". hort.net. Retrieved 29 January 2015.
12. Dykes, William (2009). "Handbook of Garden Irises" (PDF). beardlessiris.org (The Group for Beardless Irises). Retrieved 1 November 2014.
13. "Chapitre II iris a touffe et autre (partie2)". irisbotanique.over-blog.com. Retrieved 20 January 2015.
14. "Iris summary" (PDF). pacificbulbsociety.org. 14 April 2014. Retrieved 23 November 2014.
15. "Rainbow". wdtns.ru. 9 December 2014. Archived from the original on 18 May 2015. Retrieved 24 January 2015.
16. Austin, Claire (2005). Irises: A Gardener's Encyclopedia. Timber Press, Incorporated. ISBN 978-0881927306. OL 8176432M.}
17. Kojima, Keisuke; Gombosurengyin, Purevsuren; Ondognyi, Purev; Begzsurengyin, Dagvatseren; Zevgeegyin, Oyun; Hatano, Keiichiro; Ogihara, Yukio (February 1997). "Flavanones from Iris tenuifolia". Phytochemistry. Elsevier Ltd. 44 (4): 711–714. doi:10.1016/S0031-9422(96)00596-1.
18. Andersen, Oyvind M.; Markham, Kenneth R. (9 December 2005). Flavonoids: chemistry, biochemistry, and applications. CRC Press. ISBN 9780849320217. Retrieved 28 January 2015.
19. "Hui Wang (PhD)". metapop.univ-montp2.fr. Archived from the original on 10 June 2012. Retrieved 19 January 2015.
20. Choudhary, Muhammad Iqbal; Hareem, Sumaira; Siddiqui, Hina; Anjum, Shazia; Ali, Shamsher; Zaidi, Mudassir Israr (1 June 2008). "A benzil and isoflavone from Iris tenuifolia". Phytochemistry. sigmaaldrich.com. 69 (9): 1880–1885. doi:10.1016/j.phytochem.2008.03.011. PMID 18472117. Retrieved 28 January 2015.
21. Cui, Yan-Mei; Wang, Hui; Liu, Quan-Ru; Han, Mei; Lu, Yang; Zhao, Chang-Qi (17 August 2011). "Flavans from Iris tenuifolia and their effects on β-amyloid aggregation and neural stem cells proliferation in vitro". Bioorg. Med. Chem. Lett. 21 (15): 4400–4403. doi:10.1016/j.bmcl.2011.06.039. PMID 21737268. Retrieved 28 January 2015.
22. Sun, Ming-Zhou; Li, Ming-Rui; Shi, Feng-Xue; Li, Lin; Liu, Ying; Li, Lin-Feng; Xiao, Hong-Xing (July 2012). "Genomic and EST-derived microsatellite markers for Iris laevigata (Iridaceae) and other congeneric species". American Journal of Botany. 99 (7): 286–288. doi:10.3732/ajb.1100608. PMID 22739712. Retrieved 5 May 2015.
23. Lu, Zhuo; Guan, Kai-Yun; Li, Wen-Jun; Duan, Shi-Min (2014). "Phenotypic plasticity and biomass allocation of Iris tenuifolia Pall. in different habitats". Chinese Journal of Ecology. Chinese Academy of Sciences, Beijing. 33 (3): 618–623. Retrieved 28 January 2015.
24. Wang, Yan Limei; Wei, Yan Sha (January 1999). "Karyotype Analysis in Iris Tenuifolia". Journal of Qiqihar University (Natural Science Edition). Qiqihar University.
25. "Iris tenuifolia". Germplasm Resources Information Network (GRIN). Agricultural Research Service (ARS), United States Department of Agriculture (USDA). Retrieved 28 January 2015.
26. Smith, A.W.; Stearn, William T. (1972). A Gardener's Dictionary of Plant Names (Revised ed.). Cassell and Company (published 1963). pp. 68–69. ISBN 978-0304937219.
27. "Iris tenuifolia Pall". flora of Pan Himalayas. Archived from tenuifolia the original Check |url= value (help) on 18 May 2015. Retrieved 24 October 2014.
28. Limniris "Sect. Limniris Tausch" Check |url= value (help). frps.eflora.cn. Retrieved 19 January 2015.
29. Sarantsetseg, B.; Ambaga, M.; Khürelbaatar, L. (2001). "Narrow-leaf iris (Iris tenuifolia) kidney protection activity". Mongolian Medicine. Mongolian Association of Medical journals. Retrieved 19 January 2015.
30. "The exhibition "Iris Russia"". flower-iris.ru. Retrieved 23 January 2015.
31. "Iridaceae Iris tenuifolia Pall". ipni.org (International Plant Names Index). Retrieved 19 January 2015.
32. Franco, Alain (30 November 2013). "(Spec) Iris tenuifolia Pall". wiki.irises.org (American Iris Society). Retrieved 19 January 2015.
33. "Iris tenuifolia". rhs.org.uk. Retrieved 28 January 2015.
34. "Biodiversity of Altai-Sayan Ecoregion". bioaltai-sayan.ru. Retrieved 15 August 2015.
35. Jirí Kolbek, Miroslav Srutek and Elgene E. O. Box (Editor)Forest Vegetation of Northeast Asia (2003), p. 80, at Google Books
36. Samuel Hereman Blight on flowers; or figures and descriptions of the insects infesting the flower garden (1840), p. 142, at Google Books
37. "Extract from Iris tenuifolia, preparation method and application thereof". Retrieved 29 January 2015.
38. Rahman, A.U.; Nasim, S.; Baig, I.; Jalil, S.; Orhan, I.; Sener, B.; Choudhary, M.I. (June 2003). "Anti-inflammatory isoflavonoids from the rhizomes of Iris germanica". Journal of Ethnopharmacology. 86 (2–3): 177–180. doi:10.1016/s0378-8741(03)00055-2. PMID 12738083.

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• Khassanov, F. O. & N. Rakhimova. 2012. Taxonomic revision of the genus Iris L. (Iridaceae Juss.) for the flora of Central Asia. Stapfia 97:175.
• Komarov, V. L. et al., eds. 1934–1964. Flora SSSR.
• Mathew, B. 1981. The Iris. 123–124.
• Tutin, T. G. et al., eds. 1964–1980. Flora europaea.
• Waddick, J. W. & Zhao Yu-tang. 1992. Iris of China.
• Wu Zheng-yi & P. H. Raven et al., eds. 1994–. Flora of China (English edition).

Media related to Iris tenuifolia at Wikimedia Commons Data related to Iris tenuifolia at Wikispecies