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. 2022 Apr 11;9:uhac079. doi: 10.1093/hr/uhac079

Cut peony industry: the first 30 years of research and new horizons

Rina Kamenetsky-Goldstein 1,✉, Xiaonan Yu 2
PMCID: PMC9157654  PMID: 35669702

Abstract

Herbaceous peony is an ancient medicinal and ornamental crop, cultivated in China and Japan for thousands of years. Numerous varieties of different colors are popular garden plants in different continents and countries. In recent decades, peony has gained a new reputation as cut flowers. Only in Europe, in 30 years, trade in cut peony stems has increased 50 fold. Today, more than 25 countries produce cut peony flowers, with primary markets in Europe, Asia and the USA. This short review summarizes the contribution of research in plant physiology to the development of new technologies of peony production and flowering advancement. Despite the popularity of cut peonies, several factors still restrict their production: complicated flowering physiology, challenges in mass propagation, and postharvest handling. Further research of biochemical and molecular mechanisms, as well as breeding of new cultivars will promote the development of the peony industry and facilitate the creation of a Global Peony Chain for the successful marketing of this beautiful flower.

Introduction

The genus Paeonia (Paeoniaceae) includes about 35 species, native to Asia, Europe and Western North America and renowned for their ornamental and medicinal value [1–3]. Cultivated in Chinese gardens for over a millennium, peonies were regarded as a symbol of wealth and adorned the Chinese Imperial Palace Gardens. In the 8th century, peonies arrived in Japan where they became a symbol of good fortune, bravery, and honor. In the 19th century, the peonies were introduced into European and American gardens, and today it is one of the most attractive and rewarding plants in all continents [4]. According to life form, peonies are divided into tree (woody) and herbaceous species. In recent decades, herbaceous peonies are widely concerned as a new cut flower crop. The growing demand has led to new biological research and development of production technologies.

Herbaceous peonies are adapted to moderate, cold-winter climatic zones in China, Canada, the USA, and Russia. However, certain cultivars can be produced under warmer conditions in Italy, Southern France, and Southern China [5, 6]. In addition, cut peonies are also produced in New Zealand, Chile, Argentina, South Korea and Alaska.

The process of long-term breeding and selection of garden varieties of herbaceous peonies has resulted in great variability in flower forms and colors. According to the shape of the petal, flowers are characterized as single, Japanese, anemone, semi-double, bomb and double [7]. The double types are the most popular as cut flowers, due to their longer postharvest life. Selection criteria for cut peony flowers include round flower shape, upright, long and thick stalk, flower color, fragrance, resistance to pests and diseases, and good ability for storage and transportation. Although thousands of garden varieties are cultivated worldwide, only about 100 are used as cut flowers [8]. In Europe and the USA, the most popular cut flower varieties are “Sarah Bernhard”, “Duchesse De Nemours” and “Coral Charm”. In China, the assortment includes traditional European, as well as local varieties (Fig. 1).

Figure 1.

Figure 1

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Peony varieties most popular in the Dutch and Chinese Floral Auctions (Data from Y. Kohavi; X. Yu, 2020)

In Europe, trade in cut peony stems has increased 50 fold in 30 years, from three million stems produced at the end of the 1980’s in The Netherlands, to about 140 million stems from ca. 20 countries (Fig. 2). Interestingly, stem prices have remained stable, and today peony is one of the most expensive flowers in the flower trade. The Netherlands still leads in cut flower production, but Italy, Israel and France produce excellent flowers for the off-season trade in February–April, and therefore, production is constantly increasing.

Figure 2.

Figure 2

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Peony trade at the Dutch Floral Auctions. A- Dynamics of peony sales and prices from 1987 to 2020; B- production of peony cut flowers (mil stems) in 2020 in Europe (Data from: Royal Flora, Y. Kohavi).

In China, Luoyang city (Henan province) is the center of peony culture, with large living collections and gardens and dozens of annual peony exhibitions and shows. The sales volume of cut peony flowers in Luoyang increased to 15 million stems in 2021 [9]. Most of the commercial production of peony propagation material is concentrated in Heze City (Shandong province), which has become China’s largest peony planting, production, processing, export base and ornamental tourist area. In 2021, Heze produced ca. 60 million high-quality fresh cut peonies, valued at over 100 million yuan. That is 80% of the cut peony market in China [10]. In the Chinese flower market, cut peonies is are commonly sold for Chinese Mother’s Day and Internet Valentine’s Day in May, as well as for weddings. Cut peony flowers are sold mainly in Kunming, Shanghai, Beijing, Guangzhou, Shenzhen and other large domestic flower markets, and are exported to Japan, South Korea, Italy, France, the Netherlands, and Canada.

Peonies are valued in the global flower market, but in each location, they are available for only a short time in late spring and early summer. In addition, the complicated physiology of flowering and dormancy cycles and lack of advanced systems for mass propagation still restrict their production. Here we summarize the contribution of research in plant physiology to the development of new technologies of peony production and flowering advancement.

Physiology of flowering and dormancy

Annual cycle and its environmental regulation

Herbaceous peonies evolved in the climatic zone with cold winters and dry and hot summers, and their annual cycle is regulated by altering environmental conditions [11]. During winter dormancy, the underground tissues and organs carry on a series of complex physiological and biochemical reactions (Fig. 3). Renewal buds of varying sizes originate on the underground crown (Fig. 3A). In the following season, large buds that contain leaf and flower primordia, produce new flowering stems, while smaller ones remain dormant until the next season, or produce only short leafy stems (Fig. 3D). Plants flower in the spring and enter dormancy in late autumn.

Figure 3.

Figure 3

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Phenological stages and annual cycle of herbaceous peony. A. Annual life cycle comprises of three main phases, regulated by low, intermediate and high temperatures. Flower initiation occurs in summer when temperatures are high, but low temperatures are required for dormancy release and successful flowering (Adapted from 11). B. Underground crown at the beginning of the growing season; C. Storage roots with renewal buds; D. Leafy stems elongate after sprouting; E. Flowering

In early summer, the renewal underground buds contain only vegetative meristems, while by the end of the warm period the apical meristem reaches the reproductive stage and differentiates flower parts, including bracts, calyx, petals, stamens and pistil [12]. After the cold period, floral stems sprout and undergo several stages on the way to anthesis (13; Fig. 3E).

Peony is a winter-dormant and deciduous plant with massive storage roots that serve as the energy supply for dormancy release and the initial growth in spring. The major storage carbohydrate in peony is starch and the basic sugars are sucrose, myo-inositol, fructose, and glucose [14–16]. With the resumption of growth in spring, starch concentration in the roots declines but increases again after shoot emergence and throughout flowering. The ability to accumulate starch reserves in the roots during stem growth and flowering provides an adaptive advantage in environments with a short growing season [14].

Chilling requirements and growth conditions

During the annual cycle, environmental conditions affect all stages of dormancy, stem elongation, and flower development. In addition to air and soil temperature, plant hormones, nutritional status, air humidity, and photoperiod influence peony growth and development.

Several models have been used to assess chilling saturation in peony varieties. Storage at 2°C for 60 days is optimal for container-grown “Sarah Bernhardt” [17]. Surprisingly, the early flowering “Coral Sunset” required more chilling in comparison with the late-flowering “Sarah Bernhardt” [18]. The dormancy release of peony was affected by either constant or diurnal temperatures. Furthermore, in container-grown “Sarah Bernhardt” and “Katherine Fonteyn”, the fluctuating temperatures were found to provide higher chilling accumulation than the constant low temperature [19].

In Chinese variety “Da Fu Gui”, stem height, flower size and flowering rate were positively affected by both chilling and spraying by 200 or 500 mg/L GA3 [13]. However, exogenous GA3 does not promote flower differentiation in peonies and is not effective when is applied in summer, prior to flower induction and differentiation [20]. Uncooled peonies treated only with GA3, failed to flower because of flower bud abortion [21]. In the Australian subtropics, flower production is possible when artificial chilling is combined with gibberellin application [22]. In Southern China, chilling of “Hang Baishao” at 0–4°C for four weeks and application of humic acid ensured flowering and improved its quality [6].

Growth temperatures also affect the flowering process: high temperatures promote anthesis in 50–60 days, while under continuous 22/10°C (day/night) flowering occurs after 80 days. Although “Coral Sunset”, “Monsieur Jules Elie”, “Sarah Bernhardt”, and “Karl Rosenfeld” varied in their requirements for shoot emergence and flower development, the time from emergence to flower opening was similar [23].

In warm regions, high growth temperatures have a negative effect on flower development and the quality of the cut flowers and result in complete flower abortion [17].

Malnutrition, especially lack of P and K, can also cause abortion of the flower buds in forced peony [24], while application of ABA synthesis inhibitor fluridone facilitates flowering process [25].

Therefore, under field or greenhouse conditions with large temperature variations, special techniques can prevent flower abortions. Greenhouse heating during the long and cold springs in cool regions or cooling and ventilation in warm zones will certainly improve the production of strong stems and quality flowers. The same techniques will help to prevent leaf diseases caused by high air humidity or unsuitable growth temperature [5].

The effect of photoperiod on flower formation and stem elongation in herbaceous peonies is still not clearly understood. Additional lighting for short or long periods did not affect the growth rhythm of peony plants but significantly improved the quality of the cut flowers [26]. Obviously, the effect of photoperiod and light intensity and quality should be addressed in future research for the optimization of pre- and post-harvest quality of peony flower.

Propagation

Global expansion of cut peony would not be possible without efficient propagation systems. Due to slow seed germination, long juvenile period and offspring variation, seed propagation is employed only by breeders. The commercial companies and peony associations specialize in the vegetative propagation of garden varieties, and only some peony nurseries focus on traditional and new cut flower varieties.

Although asexual vegetative propagation is the most reliable approach, it is a rather slow method of plant reproduction [7]. The most popular technique to propagate herbaceous peonies is crown division, similar to other herbaceous plants, e.g. irises, daylilies or dahlias. The principle of this method is to divide the plant at its crown so that the separated units have shoot and root systems and are capable of producing new plants. In regions with a moderate climate, crowns with a root system are harvested in late summer or early autumn. Crown divisions include at least one bud, however 3–5 buds per division produce stronger and healthier plants.

The technique of small segments with renewal buds is similar to that of crown division. After harvest in late summer, the crown is divided into many small units. These units are planted in beds with light and well-drained mixture with constant humidity at a depth of 3–4 cm [27].

Root cuttings can be prepared for the hybrids of P. officinalis, P. peregrine and P. tenuifolia, which are able to form the renewal buds on storage roots [27]. Some hybrids (e.g. “Carol”, “Henry Bockstoce”, “Ellen Cowley”) can also be propagated using this method. However, most Paeonia lactiflora hybrids do not produce buds on adventitious roots.

Micropropagation of herbaceous peonies in tissue culture is based on the culture of underground buds, leaves and petioles, the induction of callus and cluster buds [28–31]. Several commercial companies are already using this biotechnology for propagating rare varieties.

Postharvest of cut flowers

The harvest of the fresh cut flowers results in internal metabolic activity and physiological changes that diminish the flower quality. In addition, mechanical damage, inappropriate environmental conditions and microbial contaminations negatively affect the post-harvest period [32]. Proper post-harvest handling not only keeps freshness and quality of cut flowers but also can considerably enlarge market period. Therefore, both short- and long-term postharvest technologies need to be developed. Cut flower preservation technologies are based on physical, chemical and biological methods.

The methods of physical preservation of cut flowers include refrigeration, wrapping, modified atmosphere and pressure reduction [33]. The efficient way to preserve freshness after harvest is low-temperature storage. Peony stems can be stored dry or wet. Dry storage is generally used for long-term storage of peony cut flowers. The longest storage life is obtained at 0°C [34], while sub-zero storage temperatures keep cut peonies fresh for 16 weeks [35]. Dry storage for the long term accelerates starch and sucrose hydrolysis, reduces the respiration rates and expands the life of cut flowers [36]. A low-oxygen controlled atmosphere provides an additional advantage in the extension of peony vase life [37]. Wet storage of flower branches in water or fresh-keeping liquid can be used only for short period [38].

Chemical preservation of cut peonies is cost-efficient and easy to carry out. Chemical preservatives include water, sugar, fungicides, inorganic salts, organic acids, plant growth regulators and other substances. Among the various preservation solutions, sucrose and 8-hydroxyquinoline are the most basic ingredients. Nano-silver, a safe and environmentally friendly broad-spectrum nano-level inorganic antibacterial material, has been proposed for the preservation of peony flowers. Carboxymethyl chitosan (CSCM) and silicon application have been proven to have a significant effect in prolonging the life of cut stems of peony [16, 37, 39–42]. Natural extracts from Chinese medicinal plants were shown as active agents for the preservation of peony stems [43].

Taken together, the application of new preservation technologies and optimization of storage conditions can certainly prolong the post-harvest value of cut peony flowers and enlarge their potential market [37].

Disease control

The most common peony diseases are blights and leaf spots (Botrytis spp., Cladosporium spp., Cercospora paeoniae, Pytophtora cactorum, Phyllosticta spp., Septoria paeoniae), rots and wilts (Fusarium sp., Verticillium albo-atrum, Rhizoctonia solani, Schlerotinia schlerotiorum, Thielaviopsis basicola), root nematodes (Rotylenchus buxophilus, Meloidogyne spp.) [44]. Viral diseases have been reported in Europe, the USA, Japan, China and New Zealand [45, 46].

The most important means in disease management is the diagnosis and identification of pathogens using morphological and molecular techniques. Recent recommendations take into account general disease management tools, published information on the specific biology of pathogens and long-term observations of peony diseases [47]. Botrytis bud blight can be controlled by regular spraying with a systemic fungicide and the destruction of dead foliage at the end of the season. Other fungal diseases are controlled by curative fungicide applications beginning as soon as symptoms develop.

Production technologies

The majority of cut flowers worldwide are produced in open fields. This method of production is suitable for locations with cold winters when underground storage organs of peonies are naturally exposed to low temperatures and fulfill their cold requirements. Sprouting and stem elongation occur in spring, and flowering peaks in May–June in Europe, USA and Canada, and in October–November in New Zealand, Australia and South America (Fig. 4).

Figure 4.

Figure 4

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Main strategies for the production of peony cut flowers. Forcing under controlled environment in containers and tunnels results in flowering advancement. Although these technologies require higher investment, early flower production secures higher prices in the special market niches.

For flowering advancement, field-grown plants in Israel, France and Italy are exposed to natural low temperatures until they receive a certain number of chill units, predetermined for each variety (48, Figs. 4, 5). Then, the tunnels are covered with plastic, in order to raise the temperatures. This technique advances flowering for about one month than in plants grown in open fields. It requires the precise control of air temperatures during dormancy breaking, stem elongation and flower bud development. However, in covered tunnels, high temperatures might cause flower abortions or malformations of flower buds [17, 20].

Figure 5.

Figure 5

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Production technologies and postharvest handling of cut peony flowers. A - Open field in South France, May 2016; B - plastic tunnel in Northern Israel, March 2014; C - pre-cooled containers with peony plants just relocated from cold storage to the greenhouse, November 2015; D - Flowering in containers, South Israel, February 2019; E- Tunnel with soil temperature control, North Israel, March 2020; G- vase life trials, Israel, 2012; H - Flower Auction in South France, May 2016 (Photo - R. Kamenetsky-Goldstein)

Growing and forcing in containers is an efficient and sophisticated technology that requires significant investment and precise control of environmental conditions during the storage and growth stages of peony development (Figs. 4, 5). A very early crop from January to March in Israel and China and in September–October in Chile meets special market niches and gets high prices in the markets. This method is based on research on flowering biology, resource allocation and nutrition [17, 48–50]. After cold storage for 5–8 weeks and gibberellin applications, peony flowering in containers is advanced by 1–3 months in comparison with field production.

New technology of peony production in greenhouses with soil temperature control has been developed in southern France and Israel. Similar to container forcing, this green technology uses artificial cooling of soil and peony storage organs during dormancy, according to the precise temperature requirements at each physiological stage (Figs. 4, 5).

Future outlook

Germplasm resources and breeding research

Introduction of germplasm resources and hybridization contribute to the breeding of new cultivars with high adaptability to specific climatic conditions and disease resistance. The limiting factors in peony genetic research and breeding are high heterozygosity, poor self-compatibility and long juvenile period. Germplasm resources of Paeonia species and cultivars, the breeding strategy, and recent progress in the isolation and functional characterization of structural and regulatory genes were recently summarized by Yang et al. [51]. P. lactiflora is the most important species in peony breeding due to large variability in flower color and form, wide ecological adaptation, and resistance to stressful environments. Microsatellite markers developed for P. lactiflora will facilitate using of the germplasm sources in the breeding process [52, 53].

Sequence-related amplified polymorphism (SRAP) molecular markers were developed for the peony genotypes from the field collections in botanical gardens of the former USSR (Belarus) and USA using genome screening. Studied plants included historic cultivars of European, American and Soviet selection, interspecific hybrids and wild species [54]. For practical breeding purposes, pollen storage at 4°C and − 20°C have been developed for hybridization among cultivars and/or species with non-synchronized flowering [55]. In addition, the breeding process can be accelerated by seedling production in containers under controlled environmental conditions and a decrease of the juvenile period to 27 months [56].

Micropropagation and biotechnology

Development of reliable in vitro protocols for fast multiplication of peony will certainly facilitate the rapid introduction of new varieties and disease-free material in commercial markets. Although laboratory protocols have been developed for numerous varieties [30, 57], large-scale propagation is still based on conventional methods. Contaminations, hyperhydricity and browning remain the main barriers in tissue culture establishment [30], and protocols are variety-specific.

Further, biotechnological applications and in vitro regeneration are important prerequisites and components of molecular research. Tissue culture provides a basic tool for many applied technologies, e.g. bioreactors, molecular breeding, or genetic transformation. Therefore, the establishment of the rapid propagation systems in tissue culture is of great significance for accelerating the cultivation marketing of new peony cultivars [58].

Molecular tools and omics research

Traditional peony breeding can be greatly reinforced by the employment of modern molecular tools, e.g. the application of molecular markers and genomics, transcriptomic, proteomic, and metabolomic studies. Fan et al. [59] reviewed recent advances in the molecular biology of Paeonia, both herbaceous and tree species and cultivars. The genetic diversity of numerous germplasm collections was assessed using a range of molecular markers (AFLP, SSR, CDDP). The construction of genetic linkage maps was performed for F1 populations. In addition to -omics and miRNAs research, numerous functional genes involved in florogenesis, flower color, dormancy and stress tolerance were discovered and investigated [51]. Currently, QTL mapping and GWASs can be used to locate the genes and linkage markers associated with target traits in specific genetic populations.

Biochemical and molecular research contributes to better understanding and possible regulation of developmental traits, from stress tolerance [60, 61] to flower color [62, 63] and biosynthesis of secondary metabolites [64]. Currently, the first priority for genetic research should be introduction of disease resistance to new cultivars, and recent reports confirm possibility of this direction [65–67].

Global Peony market chain

The development of the new industry of cut peony was successful thanks to the fruitful collaboration of many people actively involved in the production, research and marketing of this beautiful and expensive flower. National and international research programs have greatly endorsed the production of high-quality cut flowers worldwide, especially in warm-climate regions. Peony cultivation in Israel, Italy, France and South China aims at early market niche needs in February–April, in China flowering occurs from early April to mid-June. The Netherlands and Central Europe sell cut flowers in May–June, while Chile and New Zealand produce peonies in October to January. Peony production in Alaska fills the gap between Europe and USA and Southern Hemisphere. In the future, a coordinated global chain is expected to provide a constant supply of high-quality cut flowers to the international markets (Fig 6).

Figure 6.

Figure 6

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Scheme of the global production chain of cut flower peonies, using advantages of location and novel technologies. In the center: fragment of “Red Peony” by Vincent Jeannerot

Conclusions

Recent research in flowering physiology created the basis for new production technologies and flowering advancement, greatly contributing to the peony market. However, despite the popularity of cut peonies, their production is still restricted by the lack of rapid propagation systems and postharvest storage. Efficient storage and transportation techniques will allow further enlarge global peony chain and fill the gaps between various production regions. Further progress in commercial production requires breeding of new varieties, detailed studies of plant development, and improvement of production, storage, and transportation techniques. All the components of the production and marketing chain must be linked in mutually beneficial ways.

Acknowledgments

We would like to express our gratitude to the late Prof. A. Halevy for a fruitful partnership in peony projects. The results of the peony research ensued from the long-term collaboration with scientists, growers, and students. Special thanks go to Y. Kohavi, area manager of Royal Flora Holland in Israel, M. Cohen (Israel), J. Dole (USA), and many other colleagues throughout the world. This work was partly funded by grant no. 2019–220–07-5322 of the Ministry of Science and Higher Education of the Russian Federation.

Conflicts of interest statement

The authors declare no conflict of interest.

References

  • 1. Zhou S, Xu C, Liu Jet al. Out of the pan-Himalaya: evolutionary history of the Paeoniaceae revealed by phylogenomics. J Syst Evol. 2021;59:1170–82. [Google Scholar]
  • 2. Li P, Shen J, Wang Zet al. Genus Paeonia: a comprehensive review on traditional uses, phytochemistry, pharmacological activities, clinical application, and toxicology. J Ethnopharmacol. 2021;269:113708. [DOI] [PubMed] [Google Scholar]
  • 3. Yan Z, Xie L, Li Met al. Phytochemical components and bioactivities of novel medicinal food - Peony roots. Food Res Int. 2021;140:109902. [DOI] [PubMed] [Google Scholar]
  • 4. Zhang R. King of flowers: reinterpretation of Chinese peonies in early modern Europe. J South Ass History Med Sci. 2021;3:41–54. [Google Scholar]
  • 5. Kamenetsky R, Dole JM. Herbaceous Peony (Paeonia): genetics, physiology and cut flower production. Floriculture Ornamental Biotech. 2012;6:62–77. [Google Scholar]
  • 6. Zhang J, Wang X, Zhang Det al. Evaluating the comprehensive performance of herbaceous peonies at low latitudes by the integration of long-running quantitative observation and multi-criteria decision-making approach. Sci Rep. 2019;9:1–15. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 7. Rodgers A. Peonies. Portland, OR: Timber Press, Inc.; 2000. [Google Scholar]
  • 8. VBN, the Dutch Flower Auctions Association . https://www.vbn.nl/en, accessed January 2022.
  • 9. Peony Development Center of Luoyang Forestry Bureau . http://news.lyd.com.cn/system/2021/04/29/032026731_01.shtml, accessed January 2022.
  • 10. Forestry Bureau of Mudan District, Heze City . http://hzslyj.heze.gov.cn/art/2021/6/24/art_17389_10274738.html, accessed January 2022.
  • 11. Barzilay A, Zemah H, Kamenetsky R, Ran I. Annual life cycle and floral development of 'Sarah Bernhardt' peony in Israel. HortScience. 2002;37:300–3. [Google Scholar]
  • 12. Huang F, Niu H, Meng Fet al. Micro-study on flower bud differentiation of Paeonia lactiflora pall. J Northeast Agric Univ. 2009;3:57–61in Chinese. [Google Scholar]
  • 13. Cheng F, Zhong Y, Long FNet al. Chinese herbaceous peonies: cultivar selection for forcing culture and effects of chilling and gibberellin (GA3) on plant development. Isr J Plant Sci. 2009;57:357–67. [Google Scholar]
  • 14. Walton EF, McLaren G, Boldingh H. Seasonal patterns of starch and sugar accumulation in herbaceous peony (Paeonia lactiflora pall.). J Hort Sci Biotechnol. 2007;82:365–70. [Google Scholar]
  • 15. Walton EF, Boldingh HL, McLaren GFet al. The dynamics of starch and sugar utilization in cut peony (Paeonia lactiflora pall.) stems during storage and vase life. Postharvest Biol Technol. 2010;58:142–6. [Google Scholar]
  • 16. Skutnik E, Rabiza-Świder J, Jędrzejuk A, Łukaszewska A. The effect of the long-term cold storage and preservatives on senescence of cut herbaceous peony flowers. Agronomy. 2020;10:1631. [Google Scholar]
  • 17. Kamenetsky R, Barzilay A, Erez A, Halevy AH. Temperature requirements for floral development of herbaceous peony cv. ‘Sarah Bernhardt’. Sci Hortic. 2003;97:309–20. [Google Scholar]
  • 18. Fulton TA, Hall AJ, Catley JL. Chilling requirements of Paeonia cultivars. Sci Hortic. 2001;89:237–48. [Google Scholar]
  • 19. Cohen M, Eitan R, Din GY, Kamenetsky R. Effect of constant and alternating temperature regimes on post-dormancy development of herbaceous peony. Acta Hortic. 2017;1171:89–98. [Google Scholar]
  • 20. Halevy AH, Barzilay A, Kamenetsky R. Flowering advancement in herbaceous Peony. Acta Hortic. 2005;673:279–86. [Google Scholar]
  • 21. Jiang N, Zhang Q, Wang Yet al. Effects of GA3 on dormancy release, endogenous hormones levels and sugar metabolism in Paeonia lactiflora ‘Da Fugui’. J Nanjing Forestry Univ. 2020;44:26–32(in Chinese). [Google Scholar]
  • 22. Bogiatzis KC, Wallace HM, Trueman SJ. Shoot growth and flower bud production of peony plants under subtropical conditions. Horticulturae. 2021;7:476. [Google Scholar]
  • 23. Hall AJ, Catley JL, Walton EF. The effect of forcing temperature on peony shoot and flower development. Sci Hortic. 2007;113:188–95. [Google Scholar]
  • 24. Jiang N, Fang Y, Wen Let al. Effects of forcing culture on growth and flowering in Paeonia lactiflora. Non-Wood For Res. 2020;38:215–21. [Google Scholar]
  • 25. Rhie YH, Lee SY, Kim KS. ABA synthesis inhibitor inducing flowering of dormant peony without bud abortion. Acta Hortic. 2020;1291:97–102. [Google Scholar]
  • 26. Niu, L., Han, J. & Liu, Y. The effect of different illumination length on growth and the quality of cut herbaceous peony flower. Abst 28th Int Hort Cong, Lisbon, Portugal, 4242010.
  • 27. Ippolitova NY. Peonies. Moscow: Klades-Books; 2009: (in Russian). [Google Scholar]
  • 28. Gabryszewska E, Kawa-Miszczak L. Rooting in vitro and acclimatization in the greenhouse of herbaceous peony plantlets. Biotechnologia. 2010;2:172–9. [Google Scholar]
  • 29. Tian D, Tilt KM, Dane Fet al. Comparison of shoot induction ability of different explants in herbaceous peony (Paeonia lactiflora pall.). Sci Hortic. 2010;123:385–9. [Google Scholar]
  • 30. Shen M, Wang Q, Yu X, Teixeira da Silva JA. Micropropagation of herbaceous peony (Paeonia lactiflora pall.). Sci Hortic. 2012;148:30–8. [Google Scholar]
  • 31. Cazan GN, Toma F. Study on results obtained by different researchers on in vitro propagation of herbaceous peony. Sci Papers Ser B Hortic. 2017;LXI:369–76. [Google Scholar]
  • 32. Peng Y, Song L, Li L. Research progress on senescence physiology and preservation technology of fresh cut flowers. Journal of South China Normal University: Natural Science Edition. 2002;54:120–6. [Google Scholar]
  • 33. Zhang W. Causes of premature senescence and preservation techniques of fresh cut flowers. Modern Horticulture. 2008;6:23–4(in Chinese). [Google Scholar]
  • 34. Hollingsworth, D. Cutting and Storing Peony Flowers for Later Use. 2019. https://americanpeonysociety.org/wp-content/uploads/2019/04/Cutting-and-Storing-Peony-Flowers-for-Later-Use-Hollingsworth.pdf, accessed January 2022.
  • 35. Jahnke NJ, Dole JM, Bergmann BAet al. Extending cut Paeonia lactiflora pall storage duration using sub-zero storage temperatures. Agronomy. 2020;10:1694. [Google Scholar]
  • 36. Xue J, Tang Y, Wang Set al. Evaluation of dry and wet storage on vase quality of cut peony based on the regulation of starch and sucrose metabolism. Postharvest Biol Technol. 2019;155:11–9. [Google Scholar]
  • 37. Sun J, Guo H, Tao J. Effects of harvest stage, storage and preservation technology on postharvest ornamental value of cut peony (Paeonia lactiflora) flowers. Agronomy. 2022;12:230. [Google Scholar]
  • 38. Sun S. Cold storage technology of fresh cut flowers. Northern Horticulture. 2003;27:38–43. [Google Scholar]
  • 39. Tang, W. Nano study on the physiological mechanism of silver affecting the lifespan of peony cut vase. Master's Thesis, Yangzhou University, 2016. https://kns.cnki.net/KCMS/detail/detail.aspx?dbname=CMFD201701&filename=1016284257.nh. in Chinese
  • 40. Rabiza-Świder J, Skutnik E, Jędrzejuk A, Łukaszewska A. Postharvest treatments improve quality of cut peony flowers. Agronomy. 2020;10:1583. [Google Scholar]
  • 41. Chen G, Han D, Du X, Ju Z. The effect of carboxymethyl chitosan and nano-silver on the ornamental quality and physiological characteristics of cut peony flowers. Freshness and Processing. 2021;9:27–34(in Chinese). [Google Scholar]
  • 42. Song J, Li Y, Hu Jet al. Pre- and/or postharvest silicon application prolongs the vase life and enhances the quality of cut peony (Paeonia lactiflora pall.) flowers. Plants (MDPI). 2021;10:1742. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 43. Ma D, Zhao J. Effect of Chinese herbal extracts on the vase life of fresh cut peony. Forest Sci Technol Commun. 2017;8:43–68. [Google Scholar]
  • 44. Stevens S, Stevens AB, Gast KLBet al. Peonies. Manhattan, KS: Cooperative Extension Service; 1993. [Google Scholar]
  • 45. Sastry KS, Mandal B, Hammond J, Scott SW, Briddon RW. Encyclopedia of Plant Viruses and Viroids. Springer: New Delhi, 2019. [Google Scholar]
  • 46. Jia A, Yan C, Yin Het al. Small RNA and transcriptome sequencing of a symptomatic peony plant reveals mixed infections with novel viruses. Plant Dis. 2021;105:3816–28. [DOI] [PubMed] [Google Scholar]
  • 47. Garfinkel AR, Chastagner GA. Strategies to address emerging fungal diseases in peony (Paeonia lactiflora) in the United States. Acta Hortic. 2019;1237:199–206. [Google Scholar]
  • 48. Halevy AH, Levi M, Cohen M, Naor V. Evaluation of methods for flowering advancement of herbaceous peonies. HortScience. 2002;37:885–9. [Google Scholar]
  • 49. Cohen M, Kamenetsky R, Yom Din G. Herbaceous peony in warm climate: modelling stem elongation and growers profit responses to dormancy conditions. Info Process Agric. 2015;3:175–82. [Google Scholar]
  • 50. Yom Din G, Cohen M, Kamenetsky-Goldstein R. Market quality of late winter/early spring Peony after controlled dormancy: dummy regression modelling. Int J Plant Soil Sci. 2019;28:1–10. [Google Scholar]
  • 51. Yang Y, Sun M, Li Set al. Germplasm resources and genetic breeding of Paeonia: a systematic review. Hortic Res. 2020;7:107. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 52. Lin L, Cheng F-Y, Zhang QX. Microsatellite markers for the Chinese herbaceous peony Paeonia lactiflora (Paeoniaceae). Am J Bot. 2011;98:e16–8. [DOI] [PubMed] [Google Scholar]
  • 53. Sun J, Yuan J, Wang Bet al. Development and characterization of 10 microsatellite loci in Paeonia lactiflora (Paeoniaceae). Am J Bot. 2011;98:e242–3. [DOI] [PubMed] [Google Scholar]
  • 54. Vlasava NB, Michener DC, Yukhimuk ANet al. Genetic differentiation of historic cultivars of herbaceous Paeonia based on SRAP markers: documentation and conservation of botanical collections. Plant Biology and Horticulture: Theory and Innovations. 2014;139:187–99. [Google Scholar]
  • 55. Du G, Xu J, Gao C, Lu J, Li Q, Du J, Sun X. Effect of low storage temperature on pollen viability of fifteen herbaceous peonies. Biotechnol Rep. 2019;21:e00309. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 56. Jacob Y, Mastrantuono S, Ferrero F. Improving the efficiency of herbaceous Peony breeding methods. Acta Hortic. 2006;714:59–66. [Google Scholar]
  • 57. Gabryszewska E. Effects of ABA, fluridone and light quality on growth and dormancy of tissue-cultured herbaceous peony shoots. Acta Hortic. 2001;560:407–10. [Google Scholar]
  • 58. Wang H, Fu Z, Li Yet al. Research progress on ornamental peony hybrid breeding. North Hort. 2021;16:144–9(in Chinese). [Google Scholar]
  • 59. Fan Y, Wang Q, Dong Z, Yin Y, Teixeira da Silva JA, Yu X. Advances in molecular biology of Paeonia L. Planta. 2019;251:1–47. [DOI] [PubMed] [Google Scholar]
  • 60. Zhao D, Zhang X, Wang Ret al. Herbaceous peony tryptophan decarboxylase confers drought and salt stresses tolerance. Environ Exp Bot. 2019;162:345–56. [Google Scholar]
  • 61. Wu Y, Zhao D, Han C, Tao J. Biochemical and molecular responses of herbaceous peony to high temperature stress. Can J Plant Sci. 2016;6:474–84. [Google Scholar]
  • 62. Zhao D, Tao J, Han C, Ge J. Flower color diversity revealed by differential expression of flavonoid biosynthetic genes and flavonoid accumulation in herbaceous peony (Paeonia lactiflora pall.). Mol Biol Rep. 2012;39:11263–75. [DOI] [PubMed] [Google Scholar]
  • 63. Tang Y, Fang Z, Liu Met al. Color characteristics, pigment accumulation and biosynthetic analyses of leaf color variation in herbaceous peony (Paeonia lactiflora pall.). 3 Biotech. 2020;10:1–10. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 64. Meng J, Tang Y, Sun Jet al. Identification of genes associated with the biosynthesis of unsaturated fatty acid and oil accumulation in herbaceous peony ‘Hangshao’(Paeonia lactiflora ‘Hangshao’) seeds based on transcriptome analysis. BMC Genomics. 2021;22:1–21. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 65. Wang Y. The research status and prospects of peony diseases. In: Xia D (ed.), 3rd Workshop on Advanced Research and Technology in Industry (WARTIA 2017). Atlantis Press, 2017, 112–6. [Google Scholar]
  • 66. Wang X, Li J, Guo Jet al. The WRKY transcription factor PlWRKY65 enhances the resistance of Paeonia lactiflora (herbaceous peony) to Alternaria tenuissima. Hortic Res. 2020;7:57. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 67. Gong S, Hao Z, Meng J, Liu D, Wei M, Tao J. Digital gene expression analysis to screen disease resistance-relevant genes from leaves of herbaceous peony (Paeonia lactiflora pall.) infected by Botrytis cinerea. PLoS One. 2015;10:e0133305. [DOI] [PMC free article] [PubMed] [Google Scholar]

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