Pyrethrum is the most important botanical insecticide.
Pyrethrins are the oldest and the most famous compound among the natural insecticides .
«Natural pyrethrins» are the 6 active ingredients found in Pyrethrum cinerariaefolium extracts. These actives are organic esters. Therefore 6 esters are possible. They are formed by combination of either chrysanthemic acid or pyrethric acid with one of the three alcohols i.e. pyrethrolone , cinerolone and jasmolone.
Kenya has, for many years, been committed to the production of natural Pyrethrum. More than 80 years ago an enterprising agriculturist found that the species Chrysanthemum cinerariaefolium could be cultivated on the high altitude areas of Kenya, specifically at elevations of 1900- 2800 m.
A small team of workers was deployed in the 1930’s and thereafter a programme of seed production, plant breeding and clonal propagation was set up. In 1935 the Pyrethrum Board of Kenya was formally established to coordinate future marketing of the expanding crop. By the end of the second World War the major pyrethrum growing area remained, since recently, the East Africa : Tanzania, Rwanda, and Papua New Guinea . For decades, Kenya was the largest producer of pyrethrum accounting for more than 65% of the global supply. Pleagued, by fluctuated production that caused several long periodic world shortages, the region lost the confidence of the users in its ability to meet the demand, and new comers tried their skill at growing some Pyrethrum. Nowadays Tasmania in Australia, having developed large scale pyrethrum cultivation, is the new world’s biggest producer whilst Uganda, Tanzania, and Rwanda expect to raise progressively their market share by increasing cultivated surfaces.
The natural product is mainly used to protect people, household and domestic animals from pest infestation.
Pyrethrins are non-polluting as they break down quickly on exposure to light and air and they are quickly metabolized.
Pyrethrum is effective against a wide variety of insect pests, such as :
- houseflies, and other flies, mosquitoes, midges, moths, wasps, hornets, fleas, lice, ...
- cockroaches, earwigs, crickets, ants, etc. ...
Thanks to its fast action (knockdown activity), well recognized for its low mammalian toxicity (harmless for man and warm-blooded animals) and non persistence in the environment, Pyrethrum acts as a nerve agent on the insects. Pyrethrum is a natural insecticide who does its job effectively and is then rapidly degraded.
Pyrethrum can be used in insecticidal preparation alone or in combination with killing agents, such as Permethrin, Cypermethrin or Deltamethrin, with or without the addition of the synergist Piperonyl butoxide that sensibly enhances the efficacy, while being relatively non-toxic and lowering the cost price.
Pyrethrum is very widely used in various fields of application, in particular:
- for household products : aerosols, trigger sprayers, mosquito coils and mats.
- for public hygiene (surface or space treatments) against flies, cockroaches, and, mosquito control.
- in sensitive environment (low volumes, biodegradable, non persistent).
- for indoor food : protection of stored products, protection of food processing and handling, sprays and fogs for farms and dairies, sequential aerosols for restaurants.
25 kg drums