Have you ever heard of the peony? Where does this beautiful name come from?

Produced by: Science Popularization China

Author: Wei Zhourui (Institute of Botany, Chinese Academy of Sciences)

Producer: China Science Expo

Reviewer: Zhang Shuren (Institute of Botany, Chinese Academy of Sciences)

The National Botanical Garden in May is a sea of ​​flowers. Tassels cover the road, like a silver waterfall falling from the sky; peonies offer treasures, returning to the old chapter of the prosperous Tang Dynasty. There are also various other flowers, competing for beauty, mixed in, making people dazzled and reluctant to leave.

Among them, there is a small flower with a peculiar appearance, which looks like a wind chime swaying in the wind and a red heart welcoming guests with sincerity. It is the protagonist we will introduce today - the peony.

Lamprocapnos spectabilis (L.) Fukuhara

(Photo source: Wei Zhourui)

The name contains the word "peony", but there is no relationship with peony

Paeonia suffruticosa is a perennial herbaceous flower of the genus Paeonia in the family Papaveraceae. It is native to Northeast my country, the Korean Peninsula, Japan, Russia and other places. It often grows on hillside grasslands or sparse and moist deciduous forests and prefers a cool and humid environment.

How did the name "Paeonia suffruticosa" come about? "Paeonia" is used to describe its unique flower shape, while "Peony" is used because of its split leaves, which are not only similar to those of peonies, but also bloom at the same time as peonies. However, this plant is not actually related to Paeonia × suffruticosa Andrews, a peony in the genus Paeonia in the family Paeoniaceae.

Leaves of Paeonia suffruticosa (top) and Paeonia suffruticosa (bottom)

(Photo source: Wei Zhourui)

Peonies have a long history as potted flowers in China. The works of Xu Chongsi, a painter in the early Northern Song Dynasty, include peonies. Zhou Bida of the Southern Song Dynasty called it the Fish Peony, describing it as "red flowers and white stamens, shaped like two fish, piled up against each other, branches unable to withstand the pressure and drooping, as if bowing their heads", because peonies have peony leaves and peony branches (both peonies and peonies are herbaceous plants). The peonies Zhou Bida saw were "obtained from Hunan", and "I heard that there are many of them in the mountains and valleys of Jiangdong". The Hunan and Jiangsu and Zhejiang areas mentioned are actually thousands of miles away from its origin in the northeast, which shows that this plant was already an ornamental plant with mature cultivation technology at that time.

The Dicentra is known as the "Bleeding Heart" in the West, which means "bleeding heart". In 1765, Carl von Linné, the founder of modern plant taxonomy, first saw the image of the Dicentra in his student's paper. Some European documents also mentioned this plant in the early 19th century. In 1846, British horticulturist Robert Fortune introduced this flower from a nursery in Shanghai to European gardens, which was widely welcomed and quickly spread to other European countries and North America.

Today this plant is widely cultivated around the world. In addition to the common pink color, there is also a white variety. It is mainly used for gardening, cut flowers, etc.

White flower peony

(Photo source: Wei Zhourui)

Flower Album with Dancing Butterflies and Hanging Fish by Xu Chongsi, Northern Song Dynasty, Collection of the National Palace Museum, Taipei

(Photo source: National Palace Museum, Taipei)

Step by step, a delicate structure for reproduction

The peony's peculiar heart-shaped flowers have a complex structure. This is reflected in many aspects, for example, there is a small bract at the base of the pedicel, which will fall off before flowering. The flower of the peony has a bilaterally symmetrical structure, but the four petals are not consistent in shape and are divided into two layers: the outer two petals are pink, the upper part is narrow and reflexed, and the lower part is bulging and sac-shaped, which is the main part of the "purse", "pisces" or "heart shape" we see; the inner two petals are white, the tips are often attached together, and the back of the inner petals has a protrusion and is slightly purple and yellow. Among them, the stamens and pistils are wrapped by the two inner petals. There are two small green dots at the base of the stamens, which are the nectar glands of the peony, which secrete nectar to attract pollinators.

Inflorescence of peony

(Photo source: Wei Zhourui)

Anatomy of the flower of the peony

(Image source: Zhang et al., 2018, slightly modified by the author)

The peony cannot bear fruit on its own and mainly relies on bumblebees for pollination. After flowering, it produces slender capsules, which split into two petals when mature, releasing the seeds inside. There is a crystal-clear fleshy structure on the seeds of the peony, called the elaiosome, and the elaiosome is the secret of the peony seeds to move without feet. The elaiosome is rich in nutrients and is an attractive delicacy for ants. Therefore, in order to enjoy this delicacy, ants will collect the seeds of the peony and move them away to store them. These moved seeds will quietly germinate in the storage area. In this way, with the help of the ants' transportation, the peony achieves the spread of offspring.

The fruit and seeds of the peony. The transparent part of the seed is the oleosome

(Image source: Hodges 2012)

Poison is the best camouflage, stay away!

The whole plant of Dicentra is poisonous, and is known as Poisonous Beauty in the West. Like many plants in the Poppy family, the toxicity of Dicentra is attributed to a variety of alkaloids, such as protopine, dihydrosanguinarine, sanguinarine, and corydaline. Among them, the neurotoxin protopine is considered to be the most toxic component, and its content is highest in the roots of Dicentra. These toxic components can effectively protect Dicentra from being eaten by herbivores. They are a defense of plants against external stimuli and an adaptation of plants to the environment.

Is the toxicity of the peony dangerous to people who accidentally touch or eat it? The answer is yes!

The juice exuded from the broken root of the peony can cause allergies and blistering just by contacting the skin and mucous membranes. Oral ingestion of a small amount will lead to poisoning, and in severe cases, respiratory paralysis or even death. However, the alkaloids in the peony are not useless to humans and have certain medicinal value.

Molecular structure of protopine

(Image source: Zulauf et al., 2020)

A new species identity within the genus

The Dicentra was originally thought to belong to the Dicentra genus, which in classical taxonomy includes a variety of plants with bilaterally symmetrical flowers, but scientists in the field of nature have always suspected that the division of this genus is not natural enough. Later molecular systematic studies showed that the Dicentra genus is indeed different from other Dicentra species and is located at the base of the Dicentrae subfamily on the phylogenetic tree, and should be separated. As a result, the Dicentra genus eventually became independent and became the only member of the Lamprocapnos genus.

Phylogenetic tree of the Poppyaceae

(Image source: Peng et al., 2023, slightly modified by the author)

Other species of the genus Andrews also have unique flower shapes similar to those of the peony, making them excellent ornamental plants. The Dicentra formosa (Andrews) Walp. of this genus is also cultivated in the South Garden of the National Botanical Garden.

Dicentra formosa (Andrews) Walp.

(Photo source: Wei Zhourui)

Professional anti-counterfeiting, you are not the real peony!

As a traditional Chinese flower, peony has been loved by people since ancient times. It is one of the famous cultural symbols among flowers and is almost synonymous with beauty. Therefore, not only the peonies, but many other flowers that are not related to the peony are also named "peony". Here are a few of them.

The genus Peony of the Convolvulaceae family is a variant of the hairy Peony. In fact, it is a close relative of the morning glory. Its original variant also has a trumpet-shaped corolla. However, the flower shape of this variant is quite special. Not only does it have double petals, but the corolla is also irregularly torn. At first glance, it is somewhat similar to the peony. Its plant is still a common herbaceous vine in the Convolvulaceae family. It will climb around railings and tree trunks, hence the name.

Calystegia dahurica f. anestia (Fernald) Hara

(Photo source: Wei Zhourui)

The peony, also known as ranunculus, is a plant of the genus Ranunculaceae, native to West Asia and southeastern Europe. It has many varieties and different flower colors. Its flowers are large and bright, mostly double petals, and it is a frequent visitor to the fresh cut flower market.

Ranunculus asiaticus L.

(Photo source: Wei Zhourui)

Autumn Peony is a double-petaled variety of the Broken Bowl Flower, belonging to the genus Anemone of the Ranunculaceae family. Broken Bowl Flower is widely distributed in the provinces and regions of Central China, South China, and Southwest China. It often blooms at the turn of summer and autumn. It is not only a beautiful ornamental plant, but also can be used as a medicine. Here, "Broken Bowl Flower" is a serious plant professional term. Regarding the origin of this name, one theory is that in the past, in order to prevent children from picking flowers, people scared them by saying that picking flowers would break the bowl, and breaking the bowl would mean they couldn't eat, so this flower was called "Broken Bowl Flower".

Anemone hupehensis var. japonica (Thunb.) Bowles et Stearn

(Photo source: Wei Zhourui)

Hibiscus peony, a double-petaled variety of hibiscus, is a shrub of the genus Hibiscus in the Malvaceae family, also known as hibiscus. Hibiscus flowers are large and colorful, blooming all year round in a variety of colors, and are a common tree species in landscaping.

Hibiscus rosa-sinensis var. rubro-plenus Sweet

(Photo source: Wei Zhourui)

Pine Leaf Peony (Dragon Beard Peony), also known as Portulaca grandiflora, also known as sunflower and barbata, is a plant of the genus Portulaca in the family Portulacaceae, native to Brazil. It has fleshy leaves, large flowers, a variety of colors, is easy to reproduce, and is very drought-resistant and sun-resistant. It can often be seen in parks, flower beds, and potted plants in the streets and alleys.

Portulaca grandiflora Hook.

(Photo source: Wei Zhourui)

The beauty of the country has always been valued in Luoyang, where she presents a new look and new makeup.

The flowing clouds have always been like silk, but the abundant dew now has a different look.

It is suitable to appreciate it with the Golden Thread Song, and it is suitable to pick it to fold into a girl's box.

There is green grass on the waist of the skirt, which keeps the girl busy for several days in spring.

This is a poem about peony by Zhou Zhuoyong, a poet of the Qing Dynasty, which vividly describes the beautiful shape of this flower.

Spring is in its prime. It is a good time to step out of the cage, embrace nature, enjoy the company of bees and butterflies, appreciate the flowers, and enjoy this fleeting beauty.

References:

[1] Flora of China Editorial Committee, Chinese Academy of Sciences. Flora of China (Volume 32) [M]. Beijing: Science Press. 1999.

[2] Liden M., et al. Phylogeny and classification of Fumariaceae, with emphasis on Dicentra s. 1., based on the plastid gene rpsl6 intron[J]. Plant Systematics and Evolution, 1997, 206 (1-4): 411-420.

[3] Hodges L. Bleeding Heart: A Review for Growers[J]. HortTechnology, 2012, 22 (4): 517-522.

[4] Zhang XH, Zhao L. Morphology, structure and ultrastructure of staminal nectary in Lamprocapnos (Fumarioideae, Papaveraceae) [J]. Flora, 2018, 242: 128-136.

[5] Zulauf N., et al. Toxicity of bleeding heart (poisonous plant of the year 2017) Poisonous beauty[J]. Zentralblatt für Arbeitsmedizin, Arbeitsschutz und Ergonomie, 2020, 70 (3): 145-148.

[6] Peng HW, et al. A complete genus-level phylogeny reveals the Cretaceous biogeographic diversification of the poppy family[J]. Molecular Phylogenetics and Evolution, 2023. DOI: 10.1016/j.ympev.2023.107712

(Note: Latin text should be italicized.)