Iris belongs to the family Iridaceae and comprises ∼300 species worldwide (Zhang et al. 2020). Iris is known as “the flower of the rainbow” because of its colorful and attractive flowers (Xiao et al. 2023; Xu et al. 2018). It exhibits excellent adaptability, long greenery and flowering periods, and fast reproduction speed and is widely used in landscaping or as a cut flower. It is one of the most well-known ornamental plants (Xu et al. 2023; Yang et al. 2022).
Candy Lily cultivars derived from the interspecific hybridization of Iris dichotoma and Iris domestica, bloom in summer and have a long flower period and high resistance to heat, cold, drought, and barren conditions; these cultivars are popular in China (Gao et al. 2023; Liu et al. 2018). The pink- and red-flowered Candy Lily cultivars are scarce, although breeding is widely carried out. Here, we introduce a new showy pink-flowered Candy Lily cultivar, Chu Xin, which demonstrates strong resistance and summer blooming in China.
Origin
The new cultivar Chu Xin was selected from hybridization of F1-3 (the interspecific hybrid of I. dichotoma × I. domestica) as the female parent and I. domestica as the male parent. The F1-3 and I. domestica were collected from Shenyang Agricultural University, China. In 2014, 263 seedlings were obtained from the cross of F1-3 × I. domestica, and all the seedlings flowered the next year. One promising seedling, 2014-104, which has a pink flower and excellent growth vigor, was propagated in 2015 to 2017 by tissue culture. In 2018, 20 plants each of this seedling and its male and female parents were planted, for a total of 60 plants (3 plots × 20 plants). They were planted 30 × 40 cm apart in the experimental field at Yangtze Normal University, China. In 2020, seedling 2014-104 was named ‘Chu Xin’, and it was officially authorized by the American Iris Society (accession no. 20-0402).
Description
The data of ‘Chu Xin’, seed parent F1-3, and pollen parent I. domestica were collection in 2018 and 2020. Morphological characteristics including plant height, leaf length, leaf width, flower diameter, inner perianth length, inner perianth width, outer perianth length, outer perianth width, flower period, and intraday flower opening and closure time were evaluated on a randomized sample of 30 plants (3 replications × 10 plants). The data were analyzed by software SPSS 22.0.
As shown in Table 1, the plant height of ‘Chu Xin’ was 147.0 cm, which is considerably taller than the male parent I. domestica (122.6 cm). ‘Chu Xin’ demonstrated lower leaf length, leaf width and leaf length/width than female parent F1-3. The flower size of ‘Chu Xin’ (4.65 cm) is bigger than I. domestica (4.49 cm) but smaller than F1-3 (5.00 cm). Meanwhile, the inner perianth length and width, outer perianth length and width, outer perianth length/width of ‘Chu Xin’ were between I. domestica and F1-3. The outer perianth length/width of ‘Chu Xin’ was less than that of the two parents. The style of I. domestica was tubular and only slightly divided into three lips at the apex, whereas in F1-3 and ‘Chu Xin’, the styles were divided halfway into three branches (Figs. 1 and 2).
Morphological traits of F1-3, Iris domestica and new cultivar Chu Xin.
Flower characteristics of seed parent F1-3 (A), pollen parent Iris domestica (B), and new cultivar Chu Xin (C).
Citation: HortScience 59, 6; 10.21273/HORTSCI17797-24
The flowering plants of seed parent F1-3 (A), pollen parent Iris domestica (B), and new cultivar Chu Xin (C).
Citation: HortScience 59, 6; 10.21273/HORTSCI17797-24
The flower shape of new cultivar Chu Xin is similar to that of female parent F1-3 (Fig. 1). Regarding flower color, ‘Chu Xin’ is an attractive, strong purplish-pink [Royal Horticulture Society (RHS) 68B] with a vivid reddish purple (RHS N74B) perianth color and yellow-orange (RHS 15C) spots in outer perianth center; it enriched the flower color of ‘Candy Lily’. In contrast, the perianth color of F1-3 and I. domestica were pale purple (RHS N75B) and strong orange (RHS N25B), respectively. A petal spot was observed on the inner and outer perianth of I. domestica, but only on the outer perianth in F1-3 and ‘Chu Xin’. The flower period of F1-3, I. domestica, and ‘Chu Xin’ extends from 15 Jun to 20 Jul, from 8 Jun to 20 Jul, and from 18 Jun to 30 Jul, respectively, which improved the summer iris cultivar in South China. Meanwhile, the single-flower opening duration of ‘Chu Xin’ is approximately ∼9 h, opening at 9:30 AM and closing at 6:30 PM, which is longer than that of female parent F1-3, which opens at 10:00 AM and closes at 6:30 PM, lasting ∼8.5 h.
In summary, there are many differences between ‘Chu Xin’ and its parents, especially in flower color and flowering period.
Reproduction and Use
The new cultivar Chu Xin can be propagated by division or tissue culture (Gao et al. 2020). As a new cultivar, Chu Xin shows strong hot and cold tolerance, has a long flower period and a showy flower, and requires minimal management. Therefore, ‘Chu Xin’ has considerable potential for landscaping, household gardening, or use as a cut flower worldwide.
Availability
The new cultivar Chu Xin is available for research or trials. Requests for samples of cloned plants may be addressed to Dr. Gangjun Luo (e-mail: gangjunluo@163.com) or Dr. Wenji Xu (e-mail: iris_xuwenji@163.com), School of Advanced Agriculture and Bioengineering, Yangtze Normal University, Fuling 408100, China.
References Cited
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