Pyrethrum refers to several Old World plants of the genus
ChrysanthemumChrysanthemums, often called mums, are a genus of about 30 species of perennial flowering plants in the family Asteraceae, native to Asia and northeastern Europe.-Taxonomy:...
(e.g.,
C. coccineum) which are cultivated as ornamentals for their showy flower heads. It is also the name of a natural
insecticideAn insecticide is a pesticide used against insects. They include ovicides and larvicides used against the eggs and larvae of insects respectively. Insecticides are used in agriculture, medicine, industry and the household. The use of insecticides is believed to be one of the major factors behind...
made from the dried flower heads of
C. cinerariifolium and
C. coccineum. Pyrethrum was used for centuries as an insecticide and as a lice remedy ("
PersianIran , officially the Islamic Republic of Iran is a country in Western Asia. The name Iran has been in use natively since the Sassanid period and came into international use from 1935, before which the country was known internationally as Persia...
Insect Powder," "Persian Pellitory") in the
Middle EastThe Middle East is a region that spans southwestern Asia, southeastern Europe, and northeastern Africa. It has no clear boundaries, often used as a synonym to Near East, in opposition to Far East...
. It was sold worldwide under the brand Zacherlin by Austrian industrialist
J. ZacherlJohann Zacherl was an Austrian inventor, industrialist and manufacturer. Johann Zacherl made a fortune in the late 19
th century by selling dried flower heads of Chrysanthenum cinerariifolum as an insecticide....
.
Some members of
Chrysanthemum, including these two, are placed in another genus,
TanacetumTanacetum is a genus of about 70 species of flowering plant in the family Asteraceae, native to temperate regions of the Northern Hemisphere....
, by some authorities. Both genera are members of the daisy (or aster) family,
AsteraceaeThe family Asteraceae or Compositae is the second largest family of flowering plants, in terms of number of species....
. They are
perennial plantA perennial plant or perennial is a plant that lives for more than two years. When used by gardeners or horticulturalists, this term applies specifically to perennial herbaceous plants...
s with a daisy-like appearance and
white White is a color, the perception which is evoked by light that stimulates all three types of color sensitive cone cells in the human eye in nearly equal amounts and with high brightness compared to the surroundings. A white visual stimulation will be void of hue and grayness.White light can be...
petalA petal is one member or part of the corolla of a flower. The corolla is the name for all of the petals of a flower; the inner perianth whorl, term used when this is not the same in appearance as the outermost whorl and is used to attract pollinators based on its bright color...
s.
- C. cinerariifolium is called the Dalmatian chrysanthemum, denoting its origin in that region of the Balkans (Dalmatia
Dalmatia , is a region on the eastern coast of the Adriatic Sea and is situated in modern Croatia. It spreads between the island of Rab in the northwest and the Bay of Kotor, in Montenegro, in the southeast...
). It looks more like the common daisy than other pyrethrums. Its flowers, typically white with a yellow center, grow from numerous fairly rigid stems. Plants have blue-green leaves and grow to between 45 to 60 cm in height. The plant is economically important as a natural source of insecticideAn insecticide is a pesticide used against insects. They include ovicides and larvicides used against the eggs and larvae of insects respectively. Insecticides are used in agriculture, medicine, industry and the household. The use of insecticides is believed to be one of the major factors behind...
. The flowers are pulverized and the active components called pyrethrinThe pyrethrins are a pair of natural organic compounds that have potent insecticidal activity. Pyrethrin I and pyrethrin II are structurally related esters with a cyclopropane core. They differ by the oxidation state of one carbon. They are viscous liquids that oxidize to become inactivated. They...
s, contained in the seed cases, are extracted and sold in the form of an oleoresin. This is applied as a suspension in water or oil, or as a powder. Pyrethrins attack the nervous systems of all insectInsects are arthropods, having a hard exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae. They are the most diverse group of animals on the planet and include more than a million species that are already described. Insects represent more than half of all...
s, and inhibit female mosquitoMosquito is a common insect in the family Culicidae...
es from biting. When not present in amounts fatal to insects, they still appear to have an insect repellentAn insect repellent is a substance applied to skin, clothing, or other surfaces which discourages insects from landing or climbing on that surface. There are also insect repellent products available based on sound production, particularly ultrasound...
effect. They are harmful to fishA fish is any aquatic vertebrate animal that is typically ectothermic , covered with scales, and equipped with two sets of paired fins and several unpaired fins...
, but are far less toxic to mammalMammals are a class of vertebrate animals whose females are characterized by the possession of mammary glands while both males and females are characterized by sweat glands, hair, three middle ear bones used in hearing, and a neocortex region in the brain.Mammals are divided into three main...
s and birdBirds are winged, bipedal, endothermic , vertebrate animals that lay eggs. There are around 10,000 living species, making them the most numerous tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Birds range in size from the Bee Hummingbird to the ...
s than many synthetic insecticides and are non-persistent, being biodegradableBiodegradation is the material breakdown of chemicals by a physiological environment. The term is often used in relation to ecology, waste management and environmental remediation . Organic material can be degraded aerobically with oxygen, or anaerobically, without oxygen...
and also breaking downChemical decomposition or analysis is the separation of a chemical compound into elements or smaller compounds. It is sometimes defined as the opposite of a chemical synthesis. Chemical decomposition is often an undesired chemical reaction...
easily on exposure to light. They are considered to be amongst the safest insecticides for use around foodFood is any substance, usually composed of carbohydrates, fats, proteins and water, that can be eaten or drunk by an animal, including humans, for nutrition or pleasure. Items considered food may be sourced from plants, animals or other categories such as fungus or fermented products like alcohol...
. KenyaThe Republic of Kenya is a country in East Africa. Lying along the Indian Ocean, at the equator, Kenya is bordered by Ethiopia , Somalia , Tanzania , Uganda plus Lake Victoria , and Sudan . The capital city is Nairobi. Kenya spans an area about 85% the size of France or Texas...
produced 90% (over 6,000 tonneA tonne or metric ton , also referred to as a metric tonne, is a measurement of mass equal to , or approximately the mass of one cubic metre of water. It is not an SI unit but is accepted for use with the SI...
s) of the world's pyrethrum in 1998, called py for short. Production in TanzaniaThe United Republic of Tanzania is a country in central East Africa bordered by Kenya and Uganda to the north, Rwanda, Burundi and the Democratic Republic of the Congo to the west, and Zambia, Malawi and Mozambique to the south. The country's eastern borders lie on the Indian Ocean.The United...
and EcuadorEcuador , officially the Republic of Ecuador , literally, "Republic of the equator") is a representative democratic republic in South America, bordered by Colombia on the north, Peru on the east and south, and by the Pacific Ocean to the west. It is one of only two countries in South America that...
is also significant.
- C. coccineum, the Persian chrysanthemum, is native to Caucasus
The Caucasus or Caucas is a geopolitical region between at the border of Europe and Asia. It is home to the Caucasus Mountains, including Europe's highest mountain ....
and looks somewhat like a daisy. It produces large white, pink or red flowers. The leaves resemble those of ferns, and the plant grows to between 30 and 60 cm in height. The flowering period is June to July in temperate climates (Northern hemisphere). C. coccineum also contains insecticidal pyrethrum substances but it is a poor source compared to C. cinerariifolium.
- Other species such as C. balsamita and C. marshalli also contain insecticidal substances, but are less effective than the two species mentioned above.
- Pyrethroid
A pyrethroid is a synthetic chemical compound similar to the natural chemical pyrethrins produced by the flowers of pyrethrums . Pyrethroids now constitute a major proportion of the synthetic insecticide market and are common in commercial products such as household insecticides...
s are synthetic insecticides based on natural pyrethrum (pyrethrinThe pyrethrins are a pair of natural organic compounds that have potent insecticidal activity. Pyrethrin I and pyrethrin II are structurally related esters with a cyclopropane core. They differ by the oxidation state of one carbon. They are viscous liquids that oxidize to become inactivated. They...
s); one common example is permethrinPermethrin is a common synthetic chemical, widely used as an insecticide, acaricide, and insect repellent. It belongs to the family of synthetic chemicals called pyrethroids and functions as a neurotoxin, affecting neuron membranes by prolonging sodium channel activation. It is not known to...
. A common formulation of pyrethrin is in preparations containing the synthetic chemical piperonyl butoxidePiperonyl butoxide is a pesticide synergist. It does not, by itself have pesticidal properties. However, when added to insecticide mixtures, typically pyrethrin, pyrethroid, and carbamate insecticides, their potency is increased considerably....
: this has the effect of enhancing the toxicity to insects and speeding the effects when compared with pyrethrins used alone. These formulations are known as synergized pyrethrins.
Companion planting
Because of the natural insecticidal properties of the pyrethrums, they are used as companion plants, to repel pest insects from nearby crops. One might, for instance, plant them among broccoli plants in order to protect them from any of several insect pests. They are thought to repel
aphidAphids, also known as plant lice , are small plant-eating insects, and members of the superfamily Aphidoidea. Aphids are among the most destructive insect pests on cultivated plants in temperate regions...
s,
leafhopperLeafhopper is a common name applied to any species from the family Cicadellidae. Leafhoppers, colloquially known as "hoppers", are minute plant-feeding insects in the superfamily Membracoidea in the order Hemiptera...
s,
spider miteSpider mites are members of the Acari family Tetranychidae, which includes about 1600 species. They generally live on the under sides of leaves of plants, where they may spin protective silk webs, and they can cause damage by puncturing the plant cells to feed...
s, harlequin bugs,
tickTick is the common name for the small arachnids in superfamily Ixodoidea that, along with other mites, constitute the Acarina. Ticks are ectoparasites , living by hematophagy on the blood of mammals, birds, and occasionally reptiles and amphibians...
s, pickleworms and imported
cabbage wormThe term cabbage worm is primarily used for any of four kinds of lepidopteran whose larvae feed on cabbages and other cole crops. Host plants include broccoli, cauliflower, Brussels sprouts, collards, kale, mustard greens, turnip greens, radishes, turnips, rutabagas and kohlrabi...
s, among others.
Common names
Common names for
Chrysanthemum cinerariaefolium include:
- Pyrethrum
- Pyrethrum daisy
- Dalmatian pyrethrum
- Dalmatian chrysanthemum
- Dalmatian Insect Flower
- Dalmatian pellitory
Pellitory may refer to:*Anacyclus pyrethrum or pellitory, a plant containing an oil once used for toothaches and facial neuralgia*Achillea ptarmica or European pellitory, bastard pellitory, or wild pellitory*Parietaria debilis...
Common names for
Chrysanthemum coccineum include:
- Pyrethrum
- Pyrethrum daisy
- Painted daisy
- Persian chrysanthemum
- Persian Insect Flower
- Persian pellitory
Pellitory may refer to:*Anacyclus pyrethrum or pellitory, a plant containing an oil once used for toothaches and facial neuralgia*Achillea ptarmica or European pellitory, bastard pellitory, or wild pellitory*Parietaria debilis...
- Caucasian Insect Powder Plant
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