Tree Peony Cultivars Research Articles

The levels of hormone and carbohydrate in autumn and non-autumn flowering tree peonies

Mornya, P. M. P. and Cheng, F. 2011. The levels of hormone and carbohydrate in autumn and non-autumn flowering tree peonies. Can. J. Plant Sci. 91: 991–998. This study analyzed the levels of gibberellic acid (GA3), indole-3-acetic acid (IAA), cytokinin (CTK) and abscisic acid (ABA) hormones using high-performance liquid chromatography, along with the levels of sucrose, reducing sugar and starch carbohydrates by spectrophotometer during induction, initiation and differentiation stages of bud development in autumn (AFP) and non-autumn (NAFP) flowering tree peony cultivars exhibiting variations in flowering pattern. The experimental design was a randomized complete block with three replications. The variation in flowering pattern between AFP and NAFP was largely influenced by differences in GA3, IAA and CTK levels at different bud developmental stages. The flower formation cycle was completed earlier in AFP than in NAFP, hence flowering was twice annually. Cytokinin, particularly N6-(Δ2-isopentenyl)-adenosine (iPA), could be a critical hormone in autumn flowering of tree peony, as its differences in levels between AFP and NAFP remained significant across bud developmental stages. However, only GA3had negative differences across bud developmental stages, indicating that GA3levels were consistently higher in NAFP than in AFP, but the reverse holds true for CTK. The differences in GA3, IAA and CTK between AFP and NAFP were significant (P<0.05) for at least two-thirds of the bud developmental stages. Carbohydrates may not significantly influence the flowering pattern of tree peonies. Autumn flowering in tree peonies could therefore be achieved by regulating GA3, IAA and CTK levels, particularly at the induction and initiation stages of bud development to facilitate the completion of the floral formation cycle, well in advance of bud dormancy period. The findings of this study could lay the scientific basis for genetic engineering of flowering pattern of tree peonies.

The levels of hormone and carbohydrate in autumn and non-autumn flowering tree peonies

Mornya, P. M. P. and Cheng, F. 2011. The levels of hormone and carbohydrate in autumn and non-autumn flowering tree peonies. Can. J. Plant Sci. 91: 991-998. This study analyzed the levels of gibberellic acid (GA3), indole-3-acetic acid (IAA), cytokinin (CTK) and abscisic acid (ABA) hormones using high-performance liquid chromatography, along with the levels of sucrose, reducing sugar and starch carbohydrates by spectrophotometer during induction, initiation and differentiation stages of bud development in autumn (AFP) and non-autumn (NAFP) flowering tree peony cultivars exhibiting variations in flowering pattern. The experimental design was a randomized complete block with three replications. The variation in flowering pattern between AFP and NAFP was largely influenced by differences in GA3, IAA and CTK levels at different bud developmental stages. The flower formation cycle was completed earlier in AFP than in NAFP, hence flowering was twice annually. Cytokinin, particularly N6-(▵2-isopentenyl)-adenosin...

Morphological diversity of some introduced tree peony cultivars

Tree peonies, native to China, are widely cultivated in many countries, but the threat of genetic degradation in new varieties is serious due to the selection of local cultivars as parents in breeding. Hence, it is important to use introduced cultivars from different origins when breeding new varieties. To assist in en- larging the genetic basis of tree peonies, we examined 41 morphological traits of 68 introduced tree peony cultivars from the USA, France and Japan, and compared them to 21 local varieties. We found high levels of morphological diversity among cultivars; coefficients of variation based on morphological traits ranged from 14.3% to 159%, with an average of 44.5%. A principal component analysis (PCA) integrated these 41 traits into 10 principal components. Among these components, 7 were most strongly associated with the first fac- tor, representing flower characters; the other 3 were associated with the second factor, representing leaf cha- racters. Results of a cluster analysis concurred with those of the PCA analysis. All cultivars clustered into two groups: the first was characterized by those that exhibited non-leaf-chromatic, larger flower diameter, non-petal-blotch, late flower time and erect flowers, and most of them were foreign cultivars; the second in- cluded foreign and Chinese cultivars and can be further classified, and was characterized by non-leaf-chro- matic and small flower diameter. Moreover, the cluster analysis showed that most foreign cultivars were

Sequence-related amplified polymorphism analysis of tree peony (Paeonia suffruticosa Andrews) cultivars with different flower colours

SummarySequence-related amplified polymorphism (SRAP) was used to examine genetic relatedness and genetic diversity in 16 tree peony (Paeonia suffruticosa Andrews) cultivars having different flower colours. Twenty pairs of primers generated a total of 245 scorable PCR fragments among the 16 cultivars of tree peony, of which 175 bands (71.4%) were polymorphic. Genetic relationships were obtained using Nei and Li similarity coefficients. Cluster analyses of SRAP markers using the unweighted pair-group method of arithmetic averages (UPGMA) analysis, as well as Dollo and polymorphism parsimony analyses, were largely consistent. All revealed similar genetic relationships among the 16 tree peony cultivars having different flower colours. Groupings indicated that the division of cultivars was based largely on flower colour. Three main Groups were found after cluster analyses of the 16 cultivars based on SRAP markers. Cultivars with specific flower colours always grouped together. Estimates of genetic relationships and relatedness reflected the genetic diversity in flower colour in tree peony as a whole. The results also indicated that SRAP markers are informative and can provide new insights for genetic research in tree peony.

‘Sisters on Spring Outing’ (Paeonia suffruticosa ‘Zi Mei You Chun’) (Paeoniaceae): A Unique Chinese Tree Peony Cultivar Possessing Side Flowers and Bicolored Floral Discs

Large natural genetic diversifications have occurred among Chinese tree peony cultivars under the natural and artificial selections on the flower for ornamental and medicinal uses in the past over 1500 years in China. Paeonia suffruticosa ‘Zi Mei You Chun’ X.Q. Zhao & J.P. Zhao & X.Z. Zhao & X.C. Zhao & Q.X. Gao & Z.Q. Zhao & J.X. Zhao & Z.L. Suo (Paeoniaceae) is a unique cultivar possessing side flowers and bicolored floral disc belonging to the Central Plains tree peony cultivar group of China. This natural mutant is not only an outstanding ornamental, but also a valuable material for scientific research on evolution of tree peony cultivars, metabolic pathways of pigments in the floral disc, origin of floral disc in Paeoniaceae, and other issues in plant evolutionary and developmental genetics.

Comparison of anthocyanins in non-blotches and blotches of the petals of Xibei tree peony

A comparison in non-blotches and blotches of 35 cultivars of Xibei tree peony was investigated to explore flower coloration of Xibei tree peony (the second cultivar group in Chinese tree peony). With high performance liquid chromatography (HPLC) analysis, six anthocyanins including peonidin 3,5-di- O-glucoside (Pn3G5G), peonidin 3- O-glucoside (Pn3G), cyanidin 3,5-di- O-glucoside (Cy3G5G), cyanidin 3- O-glucoside (Cy3G), pelargonidin 3,5-di- O-glucoside (Pg3G5G), and pelargonidin 3- O-glucoside (Pg3G) were detected in non-blotches and blotches of petals. Total anthocyanins (TA), total flavones and flavonols (TF), and the copigmentation index (CI) were also analyzed. Cyanidin-based glycosides, which accumulated abundantly at the basal petal, resulted in blotch formation. Some peculiar cultivars with only one kind of anthocyanins or without anthocyanins in non-blotches were found in this study. For example, ‘Feng Zi Xiu Se’, ‘Ou Duan Si Lian’, and ‘Xi Wang’ contained only Pn3G5G; ‘Bing Shan Cang Yu’ and ‘Jin Bo Dang Yang’ contained only Cy3G; while no anthocyanins were found in ‘Bing Shan Xue Lian’. Several cultivars were rich in Pg-based glycosides, such as ‘Ni Hong Huan Cai’, and ‘Ju Yuan Shao Nv’. These cultivars would be excellent parents for creating new cultivars with novel flower color in the future.

`Little hedgehog' (Paeonia suffruticosa `Xiao Ci Wei')—A Unique Chinese Tree Peony Cultivar Possessing Special Bicolored Petals With Tubular Tip Structure (Paeoniaceae)

There exist large accumulations of natural genetic diversifications under the natural and artificial selections on the flower among the Chinese tree peony cultivars incited by ornamental and medicinal uses in the past over 1500 years in China. Paeonia suffruticosa `Xiao Ci Wei' is a unique Chinese tree peony cultivar possessing special bicolored petals with tubular tip structure (Paeoniaceae). This natural mutant is not only a unique ornamental, but also a valuable material for scientific researches in Evodevotics.

Applicability of Leaf Morphology and Intersimple Sequence Repeat Markers in Classification of Tree Peony (Paeoniaceae) Cultivars

Tree peony cultivars are usually classified according to flower characteristics (flower form and flower color) which are commonly affected by environmental influences and developmental levels. Judgment of flower forms may also depend on the observer. Precise and rapid cultivar identification methods are also required to manage cultivar collections as well as tree peony breeding programs. The objective of this paper is to analyze the discriminatory ability of leaf morphology and Intersimple sequence repeat (ISSR) marker systems for tree peony cultivars. As a result, although there exist large variations of leaf morphology of tree peony cultivars, the morphological characteristics of biternately compound leaves 3, 4, and 5 from the base of a shoot at the middle part of a plant are relatively stable with smaller variations within cultivars (2.7% to 27.1%, 16.8% on average) and with larger differentiations among cultivars (72.9% to 97.3%, 83.2% on average). Statistical and principal components analyses indicate that 12 leaf morphological characteristics are valuable for cultivar classification. ISSR markers present a precisely discriminatory power in tree peony cultivar classification without environmental influences. The cultivars with multiple flower forms, which makes it difficult to make judgment by means of a flower-form-based classification system, have been significantly characterized using leaf morphology or ISSR markers.

Chemical taxonomy of the Xibei tree peony from China by floral pigmentation.

Petal flavonoid compositions of 39 tree peony cultivars from Xibei (northwest China) were investigated in order to study the chemotaxonomic relationship among tree peony species. Six anthocyanins, the 3- O-glucosides and 3,5-di- O-glucosides of three anthocyanidins-pelargonidin (Pg), cyanidin (Cy), and peonidin (Pn)-exist in petals without a blotch at the base. The flowers are classified into three anthocyanidin phenotypes: 'Pn, Pg>Cy'; 'Pn, Cy'; and 'Pn, Cy>Pg'. Furthermore, the yellow pigments are identified as three flavones and three flavonols: apigenin, luteolin, chrysoeriol, and kaempferol, quercetin, and isorhamnetin, respectively. Ward's minimum-variance cluster analysis with principal component analysis produced a dendrogram using standardized scores of 20 pigment variables. Of 39 cultivars, 11 clustered with white flowered Paeonia rockii and 17 with pink flowered P. rockii. The other 11 cultivars matched either P. delavayi or P. potaninii. The result suggests that the Xibei tree peony originated mainly from P. rockii.

Effect of Chilling Treatment Methods on Flowering of Various Retarded Tree Peony Cultivars

Effect of Chilling Treatment Methods on Flowering of Various Retarded Tree Peony Cultivars

Effect of Forcing Culture in Tree Peony Cultivars on Flower Coloration and Petal Pigmentation

Effect of Forcing Culture in Tree Peony Cultivars on Flower Coloration and Petal Pigmentation

中国ボタンの花芽分化と促成能力

中国ボタン品種群の中原品種グループから9品種と, 対照品種として日本ボタン'連鶴'の合計10品種を供試し, 花芽分化・形成過程と促成能力について調査した.調査開始の6月下旬にはすべての品種においてがく片が観察され, 花芽分化の開始が確認された.その後の中国ボタンの花芽形成パターンは, (1) : 花芽分化スピードが早く, 夏季に花芽形成のスピードが鈍ることなく順調に進み, 10月上旬に雌ずい形成が完了するグループ('白鶴臥雪'など3品種), (2) : 花芽分化スピードが中程度で, 10月中旬に雌ずい形成が完了するグループ('珊瑚台'など3品種), (3)花芽分化スピードが遅く, 雌ずい形成は11月上旬にほぼ完了するグループ('錦綉球'など3品種)の3つに分類できた.促成栽培における中国ボタンの萌芽率は低温期間が4週間と短くても100%を示したが, 日本ボタン'連鶴'は極端に低下した.また, 中国ボタン'白鶴臥雪'は低温期間が短くても開花率は比較的高かった.開花の見られた中国ボタン品種における開花はすべての処理区で年内に終了した.年内促成には, 80%以上の開花率を示した'白鶴臥雪', '鳳丹', '淑女装'の3品種が適すると考えられる.

Analysis of Petal Anthocyanins to Investigate Flower Coloration of Zhongyuan (Chinese) and Daikon Island (Japanese) Tree Peony Cultivars

; Pn, Cy and Pn, Cy > Pg groups. Each group consequently specified significant features among CIELAB color notation and petal pigmentation, being adequate to characterize tree peony flowers as similar between Zhongyuan and Daikon Island cultivars, thus the cultivars of the two areas are suggested to be related to one another.

Comparative study of Chinese tree peony cultivars by random amplified polymorphic DNA (RAPD) analysis

Random amplified polymorphic DNA (RAPD) analysis was applied to Chinese tree peony cultivars ( Paeonia suffruticosa var. spontanea) to clarify their genetic relationships. Of 40 decamer primers tested, 11 produced 92 useful polymorphic DNA bands. Using these bands, 19 cultivars were distinguished and the similarity values among them were calculated. Although the values between cultivars were high, ranging from 0.722 to 0.928, a dendrogram produced by cluster analysis revealed that Chinese cultivars were largely divisible into four groups. These groups did not necessarily coincide with those classified based on flower and leaf types or petal color.

Forcing of Tree Peony for Late December Flowering Using Chinese Cultivars.

Forced flowering of Chinese tree peony cultivars was tested in comparison with Japanese cultivars. All the Chinese cultivars flowered in late December as early as one of the earliest flowering Japanese cultivars. One of the most popular Japanese cultivars flowered late in January. Flower harvest rate was over 80% in all the cultivars except one Chinese cultivar in which flower buds blasted during forcing. Some Chinese cultivars produced crown or bomb type flowers which were rarely found in Japanese cultivars. All the Chinese cultivars had short stems, suggesting that they were suitable for pot flowers rather than cut flowers.

Petal Coloration and Pigmentation of Tree Peony Bred and Selected in Daikon Island(Shimane Prefecture).

Petal coloration and pigment constitution in 38 tree peony cultivars (cvs.) from Daikon Island in Shimane Prefecture were observed.Hues of flower color ranged from red through reddish purple to purple in most cvs. Chromas and values ranged from dull to deep or dark in red-flowered cvs., very pale to dull in pink-flowered cvs. and deep to dark in purple-flowered cvs.As regards pigmentation, both 3, 5-diglucoside (3G5G) and 3-glucoside (3G) of pelargonidin (Pg) were dominant in almost all of the red-flowered cvs. Pink-flowered cvs. mainly contained the 3G5G of Pg or peonidin (Pn) but the amounts of anthocyanins were low. In purple-flowered cvs., Pn3G5G was dominant but some deep-colored cvs. had a high Cy3G content. Furthermore, as the petal color became bluer, the Pg3G and Pg3G5G contents decreased and, conversely, the Pn3G and Pn3G5G contents increased.Based on the pigmentation in tree peony cvs. from Daikon Island, Pg3G-rich 'Hohki', 'Shin Shima no Kagayaki' and 'Kohki Jishi' are recommended as useful parental cvs. to obtain more vivid red colors, and 'Hohrei' with a high Pn3G5G content may be used as a parent to obtain bluer colors in future breeding.

Influences of Pre-chilling on the Growth and Development of Flower Buds and Cut-flower Quality of Forced Tree Peony.

This study was undertaken to clarify the influences of pre-chilling on the growth and de-velopment of flower buds and the cut-flower quality of tree peony forced for December shipping.1. The growth and development of flower buds were accelerated and the number of pet-als was increased by the pre-chilling treatment. At the end of the pre-chilling period, sta-men primordia were forming in some plants of 'Hanakisoi' and 'Shimadaijin' and pistil primordium was appearing in 'Suminagashi'. Concurrently, a mass of undifferentiated tissue appeared between the developing petals and stamens. This indicates that there is a period when the differentiation of both petals and stamens proceeds simultaneously.2. The sprouting or flowering of plants in pre-chilled plots was earlier than that in non-pre-chilled ones. Flowering percentages were 100% in control plots of 'Jitsugetsunishiki', 'Yaezakura' and 'Yachiyotsubaki', and 83% in control plots of 'Shimadaijin' and 'Suminagashi', and also 83% in pre-chilled plot of 'Jitsugetsunishild'. In 'Hohki' and 'Kamatanishiki', flower-ing percentages were low or 0%, regardless of the pre-chilling treatment. In 'Kaoh', flowering percentage was 0% in control plot, whereas it was 50% in pre-chilled plot.3. Cultivars in which the flowering percentage exceeded 80% by December usually had satisfactory leaf expansion and stalk elongation and adequate flower quality even though the plants were not pre-chilled. Hence, they were marketable. The number of petals on flowers from pre-chilled plants tended to decreased by anthesis, especially in 'Suminagashi'.These results indicate that 'Jitsugetsunishild', 'Yaezakura', 'Shimadaijin', and 'Suminagashi' rarely need a pre-chilling treatment for their flowers to be marketable by December.Based on the effect of pre-chilling on flowering percentage, it is presumed that tree peony cultivars used for December market were classified into 3 flowering percentage groups: 1) improved, 2) lowered, and 3) no or small change.It is proposed that the pre-chilling treatment reduced the number of petals per flower be-cause pre-chilling favored the differentiation of stamens at the expense of petals.