Camellia flowers are highly prized for their beauty and are strongly symbolic in many cultures, particularly in Chinese culture. China is the origin of many cultivated Camellia species that now are grown throughout the world, including C. japonica (common camellia), C. chrysantha, and C. yuhsienensis. Seventy six of the 97 species in the genus are endemic to the country (Min and Bartholomew, 2007; Ming, 2000). The ornamental trees of the genus and their flowers are commonly referred to as cha-hua in Chinese (Ming, 2000; Zhu et al., 2007). According to Cothran (2004), Chinese camellias made their way to the Western world in the 18th century after being cultivated and treasured in the Orient for thousands of years. Camellias are evergreen shrubs or trees with broad, shiny, dark green leaves, and have primarily a subtropical and warm-temperate distribution. Their flowers bloom from winter to spring in a remarkable range of colors, forms, fragrance, and sizes. Besides being cherished and collected in botanical gardens and home greenhouses, camellias have long been planted as a hedge or shelter belt, or for firewood. Currently, there are more than 22,000 varieties or cultivars cataloged in the International Camellia Society (http://www.camellia-international.org/). In the United States, there are more than 2300 named cultivars registered with the American Camellia Society (https://www.americancamellias.com/).
Due to its great economic and cultural value as a living symbol of elegance and aristocracy, novel cultivars with variations in flower colors, shapes and fragrance, bloom sizes and timing, growth habits, and disease resistance are constantly sought after by amateur and commercial camellia growers throughout the world. While most Camellia species flower in winter or spring, C. azalea, a newly discovered species, blooms during midsummer and has been introduced into the breeding systems of camellia for generating new and more summer-flowering varieties (Fan et al., 2015). As the most widely grown ornamental species of the genus, C. japonica has a long history of being used in breeding for different flower shapes and colors (Shibata et al., 2004). However, C. japonica is poorly fragrant. Therefore, scented camellias, such as C. lutchuensis, have been crossed with C. japonica to produce various fragrant camellia plants (Oyama-Okubo et al., 2009). Camellia ‘Julius Nuccio’ (Nuccio et al., 2015), ‘Green 99–016’ (Green, 2014), and ‘Pink Cascade’ (Fei et al., 2013) are a few examples of new and distinct cultivars that were recently patented.
We obtained a novel interspecific hybrid cultivar, Camellia ‘Maozi’, by crossing C. japonica ‘Dahong Mudan’ (Fig. 1A) with C. pubipetala (Fig. 1B) (Wei et al., 2013). This new cultivar blooms during January–March, coinciding with three major Chinese holidays, New Year’s Day, Lunar New Year, and Lantern Festival. This timing is an important considering that cha-hua is not only an ornamental flower but also has been endowed with rich spiritual connotation in Chinese culture. Camellia ‘Maozi’ flowers are small in size and have a rare light tone of purple (Fig. 1C–E). In addition, Camellia ‘Maozi’ shows strong hybrid vigor. It grows faster than its parents (Supplemental Table 1). It has a strong root system and is resistant to partial shade. The size of its dark green foliage is similar to the male parent, smaller than the female parent. As a new addition to the camellia collection, Camellia ‘Maozi’ has the potential to be developed as both a landscaping and a high-end indoor potted plant. However, as an interspecific hybrid, Camellia ‘Maozi’ is sterile. As a result, vegetative propagation is a major approach for the cultivation of this new cultivar. In this study, we investigated floral biology, flowering phenology, and grafting and cutting propagation techniques. The results of this study are of value for understanding the reproductive biology of Camellia ‘Maozi’ and its further dissemination as a new cultivar for camellia collection.
ChenD.LiJ.-P.2013Effects of different hormone treatments on young shoot cutting in Camellia japonicaNonwood Forest Res.1153155(in Chinese with English abstract)
FanZ.LiJ.LiX.WuB.WangJ.LiuZ.YinH.2015Genome-wide transcriptome profiling provides insights into floral bud development of summer-flowering Camellia azaleaSci. Rep.59729
FeiJ.-G.FengS.C.ZhangY.-L.MoL.-B.2013Camellia plant named ‘Pink Cascade’. US 20130326780 P1
GaoC.-B.2012The influence of media on cutting propagation of Camellia chekiangoleosa. For. By-Product Spec. China 2:40–41 (in Chinese with English abstract)
GreenR.M.Jr2014Camellia plant named ‘Green 99-016’. US PP24887 P2
HuG.-P.WangG.-P.HanT.-S.LiuZ.-H.HuG.-G.ChaiH.-H.ZhangG.2013A study on the cutting propagation experiment on endemic to Guizhou Camellia kweichowensis ChangJ. Anhui Agr. Sci.4166316633(in Chinese with English abstract)
LiaoT.T.DengY.W.ZhangC.F.WuJ.B.2013A study on experiment of cutting propagation of Camellia oleifera by hormone treatmentsJ. Anhui Agr. Sci.2664665(in Chinese with English abstract)
MinT.L.BartholomewB.2007Theaceae p. 412–418. In: Z.Y. Wu P. Raven D.Y. Hong and Missouri Botanical Garden (eds.). Flora of China. Vol. 12. Science Press
MingT.L.2000Monograph of the genus Camellia. Yunnan Science and Technology Press Kunming China (in Chinese)
NuccioJ.J.NuccioT.J.NucioJ.E.2015Camellia plant named ‘Julius Nuccio’. US 20150257319 P1
Oyama-OkuboN.TanikawaN.NakayamaM.ShibataM.SuzukiK.KondoM.2009Screening of genetic resources of Camellia lutchuensis for fragrant Camellia breeding; analysis of floral scent compounds. Proc. Int. Symp. New Floricult. Crops Acta Hort. 813:399–406
RobardsK.PrenzlerP.RyanD.ZhongH.2015Camellia oil and tea oil p. 313–342. In: R.A. Moreau and Kamal-Eldin (eds.). Gourmet and health-promoting specialty oils. Elsevier
ShibataM.AidaR.KishimotoS.TanikawaN.OnozakiT.KayumiS.2004Breeding process and characteristics of Camellia Norin No.4 ‘Himenoka’ by interspecific hybridization between Camellia japonica and C. lutchuensisBull. Natl. Inst. Flor. Sci4111
van NockerS.GardinerS.E.2014Breeding better cultivars, faster: Applications of new technologies for the rapid deployment of superior horticultural tree cropsHort. Res.114022
ZhangH.-J.WangH.-H.HuY.-Y.ShenC.WangZ.-J.2015Effects of different substrates on the cutting survival rate and photosynthesis of pecanJ. Anhui Agr. Univ.42367371(in Chinese with English abstract)
ZhangX.-F.YeC.-X.LiuH.JiangJ.-Y.DaiS.-P.2012Effects of hormones and matrices on the cutting rooting of Camellia changiiChinese J. Trop. Crop321922(in Chinese with English abstract)
ZhuX.H.LuK.Y.HeY.H.2007Historical and future development of Camellia reticulata in Yunnan. Proceedings of Chinese Society of Science Annual Symposium (in Chinese)
Comparison of stem growth of Camellia ‘Maozi’ and its parental species.z