The Iris family, Iridaceae, is distributed throughout much of the world and is one of the most important horticultural families (Manning and Goldblatt, 2008). Iris sanguinea is a native perennial herb of northeastern China and Inner Mongolia, where it often grows in swamps, wet grasslands, and sunny slopes (Zhao, 1985). I. sanguinea has bright flowers and distinctive flower patterns; is tolerant to cold, drought, salt, and alkaline soils; and is resistant to pollution. It also exhibits rapid propagation; strong resistance to diseases, pests, and cold; and has a high ornamental value. It has wide ornamental applications in northern China (Shang and Wang, 2014). Wild I. sanguinea in China are rich in germplasm, but only produce a single flower color (Wang et al., 2013). In recent years, hybridization of wild I. sanguinea has resulted in successful breeding of numerous, colorful flowering cultivars. These new hybridized cultivars include Zidie, a rose–purple cultivar (Dong et al., 2014); Beautiful Lotus, a light-purple cultivar [Royal Swedish NCS color no. S3030-R60B] by crossing I. sanguinea and I. sanguinea f. albiflora (Wang et al., 2016); Tingdie, a blue–violet cultivar [Royal Horticultural Society (RHS) N89B] (Wu et al., 2017); and Bandie, a blue–violet cultivar (RHS 96B) (Wang and Wang, 2017). However, currently, there are no new cultivars with large and brightly colored flowers. In 2011, King, a new violet (RHS N88B) cultivar, was selected from the progeny of I. sanguinea and seed-harvested under natural growing conditions. King, as a new cultivar, has larger flowers with a violet perianth, blooms in June (Harbin, northeast China), and exhibits an extended period of green foliage.
Origin
In 2007, seeds produced through natural crossing were collected from native I. sanguinea plants growing in the Northeast Forestry University (NEFU), Mao-Er-Shan Experimental Forest Farm experimental nursery in Harbin, China. In Spring 2008, the seeds were sown in the same nursery. In 2011, among the progenies, plants were identified with larger flowers, a violet outer perianth with downward rolled edge, and light-colored inner perianth (code: NEFU 2011-01). The clonal system was established though ramet reproduction, and the progenies were planted in the NEFU experimental nursery for the next 5 years. All propagated plants exhibited stable and consistent phenotypically in regard to large flowering size, brilliant flower color, stable and consistent flower stem length, vigorous growth, strong environmental adaptability, uniform plant height and structure, long green leaves, flowering period, and extensive management. The flower was officially authorized to be release as ‘King’ by The American Iris Society in 2017 (accession no. 17-0988).
Description
The new cultivar King and I. sanguinea were planted separately in the NEFU experimental nursery in Harbin, China, for data collection from 2015 to 2017. Morphological characteristics included plant height, leaf length and width, leaf length/width ratio, bract length and width, bract length/width ratio, flower diameter, inner perianth length and width, inner perianth length/width ratio, outer perianth length and width, outer perianth length/width ratio, fruit length and diameter, flower period, and fruit period, which were evaluated on a randomized sample of 30 plants (3 replications × 10 plants). The data were analyzed using IBM’s SPSS Statistics 21.
‘King’ plant height (78.65 cm) was greater than I. sanguinea (55.98 cm), therefore enhancing the Iris plant height (Table 1). Leaf length (68.71 cm) and width (1.55 cm) of ‘King’ were longer and wider than I. sanguinea (59.36 cm and 1.07 cm, respectively), which increases potential ground coverage. However, the ratio of leaf length/width of ‘King’ was less than I. sanguinea (Table 1). Bract length and width of ‘King’ were 7.47 cm and 1.41 cm, respectively, which was greater than I. sanguinea; but, the ‘King’ bract length/width ratio was less than I. sanguinea.
Morphological characteristics of I. sanguinea and cultivar King.
The flower diameter of ‘King’ was 12.87 cm, which was larger than I. sanguinea (6.45 cm) and other cultivars of I. sanguinea (Dong et al., 2014; Kuwantai et al., 2018; Wang and Wang, 2017), therefore making ‘King’ an outstanding potential new Iris for landscape applications (Fig. 1). Although there have been many new Iris cultivars with various colors, ‘King’ represents a significant breakthrough with respect to flower size. ‘King’ has flowers twice as large as I. sanguinea and is a tremendous potential source for the selection of future Iris cultivars. In addition, the inner perianth color of ‘King’ was different from I. sanguinea, and both the inner and outer perianths were larger than I. sanguinea. The elliptic inner perianth color of ‘King’ was violet (RHS N88B) compared with a different violet (RHS N88A) for I. sanguinea. The inner perianth length (6.93 cm) and width (3.90 cm) for ‘King’ was significantly greater than I. sanguinea (4.48 and 1.49 cm, respectively). In contrast, the outer perianth color for ‘King’ and I. sanguinea were the same violet (RHS N88A) (Fig. 2). The outer perianth length (7.52 cm) and width (7.13 cm) were greater than the length (4.69 cm) and width (1.79 cm) of I. sanguinea. Moreover, the outer perianth length/width ratio of ‘King’ was 1.05, which is almost circular and very different from the 2.61 length/width ratio of I. sanguinea (Table 1). The flowering period for ‘King’ and I. sanguinea were the same (5–25 June), whereas the ‘King’ fruiting period (September–October) was later than I. sanguinea (August–September) (Table 1).
The flowers of (A) I. sanguinea and (B) ‘King’. ‘King’s’ inner perianth color was violet [Royal Horticultural Society (RHS) N88B] compared with a different violet (RHS N88A) for I. sanguinea. In contrast, the outer perianth color for ‘King’ and I. sanguinea were the same violet (RHS N88A).
Citation: HortScience horts 54, 8; 10.21273/HORTSCI14043-19
The flowers of (A) I. sanguinea and (B) ‘King’. ‘King’s’ inner perianth color was violet [Royal Horticultural Society (RHS) N88B] compared with a different violet (RHS N88A) for I. sanguinea. In contrast, the outer perianth color for ‘King’ and I. sanguinea were the same violet (RHS N88A).
Citation: HortScience horts 54, 8; 10.21273/HORTSCI14043-19
The flowers of (A) I. sanguinea and (B) ‘King’. ‘King’s’ inner perianth color was violet [Royal Horticultural Society (RHS) N88B] compared with a different violet (RHS N88A) for I. sanguinea. In contrast, the outer perianth color for ‘King’ and I. sanguinea were the same violet (RHS N88A).
Citation: HortScience horts 54, 8; 10.21273/HORTSCI14043-19
Single flower of ‘King’ structure, including outer perianth, inner perianth, bract, anther, ovary, and style. Inner perianth length-to-width ratio is 1.75; the outer perianth length-to-width ratio is 1.05. The color of the outer perianths are violet [Royal Horticultural Society (RHS) N88A]; the colors of inner perianths and styles are violet (RHS N88B).
Citation: HortScience horts 54, 8; 10.21273/HORTSCI14043-19
Single flower of ‘King’ structure, including outer perianth, inner perianth, bract, anther, ovary, and style. Inner perianth length-to-width ratio is 1.75; the outer perianth length-to-width ratio is 1.05. The color of the outer perianths are violet [Royal Horticultural Society (RHS) N88A]; the colors of inner perianths and styles are violet (RHS N88B).
Citation: HortScience horts 54, 8; 10.21273/HORTSCI14043-19
Single flower of ‘King’ structure, including outer perianth, inner perianth, bract, anther, ovary, and style. Inner perianth length-to-width ratio is 1.75; the outer perianth length-to-width ratio is 1.05. The color of the outer perianths are violet [Royal Horticultural Society (RHS) N88A]; the colors of inner perianths and styles are violet (RHS N88B).
Citation: HortScience horts 54, 8; 10.21273/HORTSCI14043-19
In summary, the primary differences between ‘King’ and I. sanguinea includes the flower and bract dimensions, inner perianth color, plant height, leaf size, and fruiting period. ‘King’ has an exceptional appearance for landscaping, and tremendous potential for the development of new cultivars. When planting in Harbin, China, ‘King’ usually emerges at the end of April and senesces in late October. It goes on to survive the winter and emerge the following spring.
Availability
Information about research or use of ‘King’ plants can be addressed to Dr. Ling Wang (e-mail: wanglinghlj@126.com) from the College of Landscape Architecture, Northeast Forestry University, Harbin, China.
Literature Cited
Dong, R., Zhao, H.X., Gu, D.F. & Wang, W.Q. 2014 A new Iris sanguinea cultivar ‘Zidie’ Acta Hort. Sin. 41 3 1423 1424
Kuwantai, A., Liu, Y.J., Wan, Z.Z., Liu, H.Y. & Wang, L. 2018 ‘Forest Fairy’: A new Iris sanguinea cultivar HortScience 53 1222 1223
Manning, J. & Goldblatt, P. 2008 The Iris Family: Natural History & Classification. Timber Press, Portland, OR
Shang, F.J. & Wang, L. 2014 Biological characteristics of flowering and pollination of Iris sanguinea Pratac. Sci. 31 5 1423 1424
Wang, K. & Wang, L. 2017 A new Iris sanguinea cultivar ‘Bandie’ Acta Hort. Sin. 44 S2 1423 1424
Wang, Z.Z., Wang, C., Yang, Y. & Liang, C.B. 2013 Research progress and development trend of wild perennial flower Iris sanguinea Southern Hort. 24 2 1423 1424
Wang, L., Xia, D.M., Li, Y.N., Peng, H.M., Chen, H.L. & Fan, L.J. 2016 A new Iris sanguinea cultivar ‘Beautiful Lotus’ Acta Hort. Sin. 43 8 1423 1424
Wu, L.Y., Jin, H., Chen, Y.N., Zhang, B.H. & Wang, L. 2017 A new Iris sanguinea cultivar ‘Tingdie’ Acta Hort. Sinica. 44 S2 1423 1424
Zhao, Y.T. 1985 China flora. Vol. 16, no. 1. Science Press, Beijing, China
