CULTIVAR AND GERMPLASM RELEASES

HORTSCIENCE 53(5):729–731. 2018. https://doi.org/10.21273/HORTSCI12770-17 Yuntian Nursery, and propagated via grafting on O. fragrans rootstock. The resulting plants were cultivated and observed for field perfor- Osmanthus fragrans ‘Cai Ye Gui’, mance in , for 9 years. Osman- thus fragrans ‘Cai Ye Gui’ (syn. O. fragrans a Variegated Cultivar ‘Variegatus’) was named and is being released based on variegated foliage and stable field Tingting Tong performance. Central South University of Forestry and Technology, 498 South Shaoshan Rd., , Hunan 410004, ; and Changsha Environmental Description and Performance Protection College, 10 Jinggui Road, Changsha, Hunan 410004, China Osmanthus fragrans ‘Cai Ye Gui’ is an Lili Shao evergreen shrub or small tree that has Hunan Biological and Electromechanical College, 2nd Yuanda Road, a moderate-sized, rounded form and reaches Changsha, Hunan 410618, China up to 5 m tall and 2.5 m wide over 17 years in Yuntian, Zhuzhou, Hunan. Leaves are 7.4–10 Zhonghua Peng1 cm long by 2.6–3.5 cm wide and elliptic to Central South University of Forestry and Technology, 498 South Shaoshan elliptic-lanceolate with acuminate apex, cu- neate or broadly cuneate base, and serrulate Road, Changsha, Hunan 410004, China leaf margin. A unique characteristic of this Youping Sun1 selection is its variegated leaves. All refer- ences to color numbers are from the Royal Department of Plants, Soils, and Climate, UT State University, 4820 Old Horticultural Society and Flower Council of Main Hill, Logan, UT 84322 Holland (2001). Leaf color is growth-stage dependent (Fig. 1B). The middle part of new Additional index words. cutting propagation, O. fragrans ‘Variegatus’, Oleaceae, sweet leaves is carmine (59B) or dark magenta osmanthus (79A). The color at the edge of the adaxial and abaxial surfaces of new leaves is laven- der blush (73A and 73B, respectively). Ma- Osmanthus fragrans Lour., commonly var. aurantiaeus (Makino, 1902) or O. auran- ture leaves are light yellow (11D) mixed with known as sweet osmanthus, sweet olive, tea tiacus (Nakai and Koidzumi, 1922). Osman- green (134A) in the central part, whereas turn olive, and fragrant olive, is a species belong- thus fragrans var. ginmokusei (silver light yellow (11D) at the edge of the adaxial ing to Oleaceae. It was originally named Olea osmanthus) is a white-blossoming subspecies, and abaxial surfaces. fragrans Thunb. (Murray, 1784). Sweet whereas O. fragrans var. kinmokusei (gold Starting from 2012, a systematic field trial osmanthus is native to Asia. It comes from osmanthus) is a subspecies producing orange was conducted to observe the field perfor- the Himalayas through southern China, flowers (Chang et al., 1996; Huxley, 1992). mance of this new cultivar over three con- southern Japan, Southeast Asia and continues More than 200 sweet osmanthus cultivars are secutive years. Osmanthus fragrans ‘Cai Ye as far south as Cambodia and Thailand named in China, e.g., O. fragrans ‘Yinbi Gui’ plants propagated from stem cuttings (Chang et al., 1996). Sweet osmanthus is an Shuanghui’, ‘Qiannan Guifei’, ‘Huaan Tian- were grown in raised beds under 30% shade- evergreen shrub or small tree that grows up xiang’, ‘Meiyuan Bai’, and ‘Zhuye Yin’ cloth with well-drained regular red soil Ao. to 3–12 m tall. Leaves are 7–15 cm long and (Xiang, 2008; Xiang et al., 2014; Zang et al., The dark green seedlings from the aforemen- 3–5 cm broad with an entire or serrulate 2014). tioned sources were used as the comparison. margin. It produces strongly fragrant and In this paper, a new cultivar named Plant height, leaf length, and leaf width were small flower clusters in an assortment of O. fragrans ‘Cai Ye Gui’ (syn. O. fragrans measured on three plants of each type. The white, pale yellow, yellow, or orange-yellow ‘Variegatus’) is described and being released relative chlorophyll content [Soil and Plant colors in late summer and autumn. The purple- for germplasm purposes. It is a selection from Analyzer Development (SPAD) reading] of black drupe fruit is 10–15 mm long and O. fragrans seedlings with variegated fo- 10 leaves each plant was recorded at the edge matures in spring. liage. It was discovered by Mr. Jianxiong of the leaf blade along the distal half using The flowers of sweet osmanthus have long Yi, the owner of Yuntian Nursery (Zhuzhou, a handheld chlorophyll meter (measured as been used for traditional Chinese medicine Hunan, China), and has been licensed to the optical density; Minolta Camera Co., as an herbal tea remedy, in Chinese cuisine Jiangsu Ao-Yang Ecological Agriculture Osaka, Japan). Analysis of variance was as osmanthus-scented jam, and in northern and Forestry Ltd. (, Jiangsu, China). performed using JMP (Version 12, SAS In- India as an insect repellent (Royal Botanic stitute, Inc., Cary, NC). Means separation Gardens, Kew, 2017; Zhou, 2008). Else- between O. fragrans ‘Cai Ye Gui’ and where in the world, it is cultivated as an Origin O. fragrans was conducted using the Stu- ornamental plant for its deliciously fragrant Osmanthus fragrans ‘Cai Ye Gui’ was dent’s t test at a = 0.05. Osmanthus fragrans flowers in gardens in Asia, Europe, and North derived from wild-collected seeds (4000 ‘Cai Ye Gui’ were constantly shorter than America. Several taxa with various flower kg) purchased in 1999 from retail nurseries in O. fragrans dark green seedlings over three colors have been selected for garden use. In the southern China provinces of Guangxi, consecutive years of observations (Table 1). Japan, O. fragrans var. thunbergii produces Hunan, Hubei, and Jiangxi. These seeds The leaf of O. fragrans ‘Cai Ye Gui’ was also gold-orange flowers (Makino, 1927). A variety were put into wet sand for cold stratification smaller than that of O. fragrans dark green with red-orange flowers is named O. fragrans at 4 C for 4 months. Stratified seeds were seedlings. This result indicates that O. fra- then sown into field plots with regular red grans ‘Cai Ye Gui’ has the potential of being soil in Yuntian Nursery, Zhuzhou, Hunan produced into a compact form with smaller (2759#45$N, 11311#13$E, elevation 67 m). leaves. Compared with O. fragrans dark Received for publication 7 Dec. 2017. Accepted for The type of the red soil is Orthic Acrisols (Ao) green seedlings, leaf index (length/width) of publication 4 Feb. 2018. 1Corresponding authors. E-mail: 345492902@qq. based on the soil map of China (Zhang, 1990). O. fragrans ‘Cai Ye Gui’ was reduced at the com or [email protected]. Of hundreds and thousands of regular dark first year of observation, but did not change at This is an open access article distributed under the green seedlings, a seedling with variegated the second and third year. Obviously, SPAD CC BY-NC-ND license (http://creativecommons. foliage stood out (Fig. 1A). This seedling was reading of O. fragrans ‘Cai Ye Gui’ was less org/licenses/by-nc-nd/4.0/). discovered by Mr. Jianxiong Yi, the owner of than that of O. fragrans dark green seedlings.

HORTSCIENCE VOL. 53(5) MAY 2018 729 Culture and Use Like other O. fragrans cultivars, O. fra- grans ‘Cai Ye Gui’ is a heliophilous species. It prefers moist, well-drained fertile soil in full sun or partial shade. The average daily light integral ranged from 15.2 to 38.4 mol·m–2·d–1 in a closest weather station in Changsha, Hunan (Sun et al., 2015). Osman- thus fragrans ‘Cai Ye Gui’ grow well at ambient temperature ranging from 15 to 28 C. It is a cold hardy cultivar that can survive at a temperature of –12 C (USDA cold hardiness zone 7a). Once established, O. fragrans ‘Cai Ye Gui’ shows similar drought tolerance to the species. No major insect and pest problems have been observed. It is suitable for landscape use as a single specimen, an evergreen screen, or a founda- tion plant and mass planting.

Propagation Softwood and semihardwood cuttings are suitable for the propagation of O. fragrans ‘Cai Ye Gui’. The best time for collecting softwood and semihardwood cuttings is in June to early July and in September to early October, respectively. In July 2013, softwood Fig. 1. Variegated foliage of Osmanthus fragrans ‘Cai Ye Gui’ (A), leaves of O. fragrans ‘Cai Ye Gui’ cuttings were collected from the top outer (top) and O. fragrans (bottom) with a newly developed leaf on the left and a mature leaf on the right canopy of healthy O. fragrans ‘Cai Ye Gui’ (B), 2-year-old O. fragrans ‘Cai Ye Gui’ plants from softwood cutting propagation in a field (C), plants grown in Yuantian, Zhuzhou, Hunan. semihardwood cuttings of O. fragrans ‘Cai Ye Gui’ in containers (D), and a representative cutting –1 The subterminal cuttings, 7–10 cm long with treated with 1,500 mg·L 1-naphthaleneacetic acid formed roots after 60 d (E). two to four nodes, were collected from one to two nodes basipetal from the meristems. All cuttings were stripped off the bottom leaves Table 1. Growth, leaf size, and relative chlorophyll content [Soil and Plant Analyzer Development (SPAD) leaving only two top leaves. The bottom of reading] of Osmanthus fragrans and O. fragrans ‘Cai Ye Gui’ plants grown in field plots for three the cuttings was trimmed into a horseshoe consecutive years. Three plants O. fragrans ‘Cai Ye Gui’ propagated from stem cuttings and three shape, and the top of the cuttings was sealed O. fragrans seedlings were chosen for this observation. with wax. The cuttings were then soaked for Leaf 4 h at a depth of 2–3 cm in solutions with Yr Plant Ht (cm) Length (L) (mm) Width (W) (mm) L/W SPAD different concentrations (0, 50, 75, 100, or 1 O. fragrans 86 az 77.9 a 33.2 ba 2.3 a 54.1 a 125 mg·L–1) of 1-naphthaleneacetic acid O. fragrans ‘Cai Ye Gui’ 44 b 49.8 b 25.7 b 1.9 b 29.0 b (NAA). ABT1 talc powder [a.i. 30% indole- 2 O. fragrans 113 a 85.2 a 36.3 a 2.4 a 57.5 a 3-acetic acid (IAA) and 20% NAA; O. fragrans ‘Cai Ye Gui’ 77 b 58.8 b 26.9 b 2.2 a 38.9 b Horticulture Ltd., Shanghai, China] were also 3 O. fragrans 137 a 92.9 a 44.0 a 2.1 a 54.7 a O. fragrans ‘Cai Ye Gui’ 104 b 67.2 b 32.8 b 2.1 a 44.7 b compared. Three replications of 30 cuttings z each were prepared for each treatment. Means with same lowercase letters within a year and dependent variable are not significantly different by the Student’s t test at a = 0.05. All cuttings were then inserted 3–5 cm deep in well-drained regular red soil (Ao, pH: 5.5–7.0) in raised beds (1.3–1.5 m wide) percentage of 90.2% at a concentration of 100 Table 2. Cutting propagation of Osmanthus (Fig. 1C). Raised beds were treated with mg·L–1, which was an increase of 64% com- fragrans and O. fragrans ‘Cai Ye Gui’ at 0.125% of carbendazim 50% wettable pow- pared with the control (distilled water) different concentrations of 1-naphthaleneacetic der (a.i. carbandazim, 50% w/w; Kenvos (Table 2). No significant difference in the acid (NAA). Thirty cuttings of each of three replications were prepared, soaked for 4 h at Biotech Co., Ltd., , Zhejiang, rooting was observed between O. fragrans China) 3 d before the cuttings were inserted. a depth of 2–3 cm in solutions at different NAA and O. fragrans ‘Cai Ye Gui’. When NAA Low tunnels with polyethylene plastic were concentrations, and inserted 3–5 cm deep in and ABT1 were compared, the percentage of made to cover the raised beds to maintain well-drained regular red soil in raised beds. Data were collected at 40 d after treatment. humidity the first 2 weeks and then removed cuttings with roots was 90.2% and 78.8% for O. fragrans ‘Cai Ye Gui’ treated with NAA at 100 Rooting (%)z for the remainder of the experiment. After 40 d, –1 the number of cuttings with roots, number mg·L or with ABT1 talc powder, respectively NAA O. fragrans of roots per cutting, or the length of all roots (Table 3). The rooting percentage of O. fra- (mg·L–1) O. fragrans ‘Cai Ye Gui’ were recorded. Data analysis was performed grans ‘Cai Ye Gui’ was similar to that of O. 0 27.9 ± 2.1z ey 26.1 ± 2.3 d as described previously. Means separation fragrans when NAA or ABT1 was used. In 50 48.2 ± 3.4 d 47.3 ± 3.6 c among hormone treatments or between addition, there were no differences between O. 75 61.8 ± 4.5 c 62.3 ± 4.2 b fragrans and O. fragrans ‘Cai Ye Gui’ in terms 100 91.7 ± 5.7 a 90.2 ± 5.5 a O. fragrans ‘Cai Ye Gui’ and O. fragrans 125 78.2 ± 6.3 b 71.4 ± 6.2 b was conducted using the Tukey’s honestly of the number of roots per cutting and the z Mean ± SE. significant difference multiple comparison or length of the longest root. These results in- yMeans with same lowercase letters within Student’s t test at a = 0.05, respectively. dicated that ABT1 was a less effective rooting a column are not significantly different by the NAA significantly promoted the rooting of agent than NAA for the propagation of O. Tukey’s honestly significant difference multiple O. fragrans ‘Cai Ye Gui’ with the highest fragrans ‘Cai Ye Gui’ via softwood cutting. comparison at a = 0.05.

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