''Lonicera japonica'', known as Japanese honeysuckle
and golden-and-silver honeysuckle, is a species of
honeysuckle
Honeysuckles are arching shrubs or twining vines in the genus ''Lonicera'' () of the family Caprifoliaceae, native to northern latitudes in North America and Eurasia. Approximately 180 species of honeysuckle have been identified in both conti ...
native to eastern Asia. It is often grown as an ornamental plant, but has become an
invasive species
An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species ad ...
in a number of countries. Japanese honeysuckle is used in traditional Chinese medicine.
Description
''Lonicera japonica'' is a twining
vine
A vine (Latin ''vīnea'' "grapevine", "vineyard", from ''vīnum'' "wine") is any plant with a growth habit of trailing or scandent (that is, climbing) stems, lianas or runners. The word ''vine'' can also refer to such stems or runners themselv ...
able to climb up to high or more in
tree
In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...
s, with opposite, simple oval
leaves
A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...
long and broad. When its stems are young, they are slightly red in color and may be fuzzy. Older stems are brown with peeling bark, and are often hollow on the inside.
The
flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechani ...
s are double-tongued, opening white and fading to yellow, and sweetly vanilla scented. The
fruit
In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering.
Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particu ...
, which is produced in fall,
is a black spherical
berry
A berry is a small, pulpy, and often edible fruit. Typically, berries are juicy, rounded, brightly colored, sweet, sour or tart, and do not have a stone or pit, although many pips or seeds may be present. Common examples are strawberries, raspb ...
diameter containing a few
seed
A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiospe ...
s. While the nectar from the flowers can be safely consumed by humans, all other parts of the plant have the potential to be toxic.
Subspecies
There are three
subspecies
In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
of ''Lonicera japonica'':
Cultivation, management, and uses
Even though it is a highly invasive and destructive plant, this species is often sold by American nurseries as the
cultivar
A cultivar is a type of cultivated plant that people have selected for desired traits and when propagated retain those traits. Methods used to propagate cultivars include: division, root and stem cuttings, offsets, grafting, tissue culture, ...
'Hall's Prolific' (''Lonicera japonica'' var. ''halliana''), and in the UK as the cultivar 'Halliana'. The cultivar is also known as Hall's Japanese honeysuckle. It is an effective
groundcover and has strong-smelling
flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechani ...
s. It can be cultivated by
seed
A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiospe ...
,
cuttings, or
layering
Layering has evolved as a common means of vegetative propagation of numerous species in natural environments. Layering is also utilized by horticulturists to propagate desirable plants.
Natural layering typically occurs when a branch touches ...
. In addition, it will spread itself via
shoot
In botany, a plant shoot consists of any plant stem together with its appendages, leaves and lateral buds, flowering stems, and flower buds. The new growth from seed germination that grows upward is a shoot where leaves will develop. In the spri ...
s if given enough space to grow. The variety ''L. japonica'' var. ''repens'' has gained the
Royal Horticultural Society
The Royal Horticultural Society (RHS), founded in 1804 as the Horticultural Society of London, is the UK's leading gardening charity.
The RHS promotes horticulture through its five gardens at Wisley (Surrey), Hyde Hall (Essex), Harlow Carr (Nort ...
's
Award of Garden Merit
The Award of Garden Merit (AGM) is a long-established annual award for plants by the British Royal Horticultural Society (RHS). It is based on assessment of the plants' performance under UK growing conditions.
History
The Award of Garden Merit ...
.
Japanese honeysuckle flowers are edible to humans and appreciated for their sweet-tasting nectar. The flowers can also be a significant source of food for deer, rabbits, hummingbirds, and other wildlife.
Herbal medicine
In
traditional Chinese medicine
Traditional Chinese medicine (TCM) is an alternative medical practice drawn from traditional medicine in China. It has been described as "fraught with pseudoscience", with the majority of its treatments having no logical mechanism of action ...
,
''Lonicera japonica'' is called ''rěn dōng téng'' ();
literally "winter enduring vine") or ''jīn yín huā''
(; literally "gold-silver flower," in reference to the presence of flowers of different age on the same plant as each flower change from white (silver) to yellow (gold)). Alternative Chinese names include ''er hua'' (二花) and ''shuang hua'' (雙花), meaning ''double-
olor
An olor is a piece of cowhide or plastic tied onto a male goat like a skirt. It is used by Kenyan goatherders to prevent bucks from impregnating the female goats during times of drought.
References
External links
Society of Kenya
Contra ...
flowers''.
The dried leaves and flowers (Flos Lonicerae Japonicae) are employed in traditional Chinese medicine, where they are believed to be of use to treat fever, cold-related headache, cough, thirst, certain inflammation including sore throat, skin infection, and tumor necrosis.
Antiviral action
The antiviral action of
loniflavone, a compound found in ''Lonicera japonica'', has been investigated in computational studies, in which the ability of this compound to bind with high affinity to the spike protein of
SARS-CoV-2
Severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) is a strain of coronavirus that causes COVID-19 (coronavirus disease 2019), the respiratory illness responsible for the ongoing COVID-19 pandemic. The virus previously had a ...
has been demonstrated, an early step towards drug development for the disease caused by that virus.
As an invasive species
Japanese honeysuckle has become naturalized in Argentina, Australia, Brazil, Mexico, New Zealand, and much of the US, including Hawaii, as well as a number of Pacific and Caribbean islands. It is classified as a noxious weed in Texas, Illinois, and Virginia, and is banned in Indiana and New Hampshire. It is listed on the New Zealand
National Pest Plant Accord
The National Pest Plant Accord (NPPA) is a New Zealand agreement that identifies pest plants that are prohibited from sale and commercial propagation and distribution.
The Accord initially came into effect on 1 October 2001 between regional coun ...
as an unwanted organism.
''Lonicera japonica'' was initially brought to the United States from Japan in the early 1900s as an ornamental plant. It is still deliberately planted in the United States for reasons such as erosion control or forage for deer, but has become invasive in many areas.
It prefers to invade areas that have been disturbed, such as roadsides or floodplains. It will generally only invade forests when the canopy has been opened by logging or fallen trees, as it grows less vigorously in the shade. Once it has invaded an area, ''Lonicera japonica'' grows rapidly and outcompetes native plants for sunlight and nutrients.
It proliferates using both
sexual
Sex is the biological distinction of an organism between male and female.
Sex or SEX may also refer to:
Biology and behaviour
*Animal sexual behaviour
**Copulation (zoology)
**Human sexual activity
**Non-penetrative sex, or sexual outercourse
** ...
and
vegetative reproduction
Vegetative reproduction (also known as vegetative propagation, vegetative multiplication or cloning) is any form of asexual reproduction occurring in plants in which a new plant grows from a fragment or cutting of the parent plant or spec ...
, producing seeds that are spread by animals and expanding locally via
rhizome
In botany and dendrology, a rhizome (; , ) is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow hori ...
s.
Eventually, it will form a dense thicket which prevents other plant species from germinating in that area.
Due to its suppression of germination in the understory, ''Lonicera japonica'' also prevents the regeneration of trees.
Management of invasive ''Lonicera japonica'' has been achieved through a variety of means. Small patches can be removed by hand, or using simple digging tools,
but all plant parts including roots and rhizomes must be removed to prevent resprouting.
Larger patches can be removed through repeated mowing, but application of herbicide is also recommended to prevent regrowth.
There has been some study of using
controlled burns to remove ''Lonicera japonica'', but the underground portion of the plant is usually able to survive and resprout, limiting the effectiveness of this method.
Browsing by herbivores may limit its growth, but is unlikely to fully eliminate it.
There is currently no known
biological control
Biological control or biocontrol is a method of controlling pests, such as insects, mites, weeds, and plant diseases, using other organisms. It relies on predation, parasitism, herbivory, or other natural mechanisms, but typically also invo ...
for ''Lonicera japonica''.
Chemistry
''Lonicera japonica'' contains
methyl caffeate,
3,4-di-O-caffeoylquinic acid,
methyl 3,4-di-O-caffeoylquinate,
protocatechuic acid
Protocatechuic acid (PCA) is a dihydroxybenzoic acid, a type of phenolic acid. It is a major metabolite of antioxidant polyphenols found in green tea. It has mixed effects on normal and cancer cells in ''in vitro'' and ''in vivo'' studies.
Biolo ...
,
methyl chlorogenic acid, and
luteolin
Luteolin is a flavone, a type of flavonoid, with a yellow crystalline appearance.
Luteolin is the principal yellow dye compound that is obtained from the plant '' Reseda luteola'', which has been used as a source of the dye since at least the f ...
. The two biflavonoids,
3′-O-methyl loniflavone and
loniflavone, along with luteolin and
chrysin, can be isolated from the leaves. Other phenolic compounds present in the plant are
hyperoside
Hyperoside is a chemical compound. It is the 3-''O''-galactoside of quercetin.
Natural occurrences
Hyperoside has been isolated from ''Drosera rotundifolia'', from the Lamiaceae ''Stachys sp.'' and ''Prunella vulgaris'', from ''Rumex acetosella ...
,
chlorogenic acid
Chlorogenic acid (CGA) is the ester of caffeic acid and (−)-quinic acid, functioning as an intermediate in lignin biosynthesis. The term "chlorogenic acids" refers to a related polyphenol family of esters, including hydroxycinnamic acids (caffe ...
, and
caffeic acid
Caffeic acid is an organic compound that is classified as a hydroxycinnamic acid. This yellow solid consists of both phenolic and acrylic functional groups. It is found in all plants because it is an intermediate in the biosynthesis of lignin, one ...
. The two secoiridoid glycosides,
loniceracetalides A and
B, can be isolated, together with 10 known iridoid glycosides, from the flower buds. The plant also contains the saponins
loniceroside A and
B and the antiinflammatory
loniceroside C.
References
{{Taxonbar, from=Q161083
japonica
Flora of China
Flora of Eastern Asia
Medicinal plants of Asia
Dietary supplements
Plants used in traditional Chinese medicine
Garden plants of Asia
Drought-tolerant plants
Groundcovers
Vines
Introduced plants of South America
Plants described in 1784