vZaZaa.com

Catnip
Nepeta is a genus of about 250 species of flowering plants in the family Lamiaceae. The members of this group are known as catnip or catmint because of their famed effect on cats—nepeta pleasantly stimulates cats' pheromonic receptors. The genus is native to Europe, Asia and Africa, with the highest species diversity in the Mediterranean region east to mainland China. It is now common in North America as a weed. Most of the species are herbaceous perennial plants, but some are annuals. They have sturdy stems with opposite heart-shaped, green to grayish-green leaves. The flowers are white, blue, pink or lilac and occur in several clusters toward the tip of the stems. The flowers are tubular and spotted with tiny purple dots. The scent of the plant has a stimulating effect on cats.

Oil isolated from catnip by steam distillation is a repellent against insects, in particular mosquitoes, cockroaches and termites. Research suggests that in a test tube, distilled nepetalactone, the active ingredient in catnip, repels mosquitoes ten times more effectively than DEET, the active ingredient in most insect repellents, but that it is not as effective as a repellent on skin.

Effects on cats
Both true catnip and Faassen's catnip have a sharp, biting taste, while the taste of giant catmint is bland.

Catnip and catmints are mainly known for the behavioral effects they have on cats, particularly domestic cats. When cats sense the bruised leaves or stems of catnip, they may roll over it, paw at it, chew it, lick it, leap about and purr, often salivating copiously. Some cats will also growl and meow. This reaction only lasts for a few minutes before the cat loses interest. It takes up to two hours for the cat to "reset" after which it can come back to the catnip and have the same response as before. Young kittens and older cats are less likely to react to catnip.

Approximately two thirds of cats are susceptible to the behavioral effects of catnip. The phenomenon is hereditary; for example, most cats in Australia are not susceptible to catnip, since Australian cats are drawn from a relatively closed genetic pool. It elicits such a response in only some cats—and it is such a dramatic response—because a genetic element is involved that is enriched in domesticated breeds. There is some disagreement about the susceptibility of lions and tigers to catnip. Some claim that all lions and tigers are affected by catnip, but others say that lions are affected but not tigers. In a recent television documentary released by Animal Planet called Stalking the Jaguar, the scientists on the mission used a form of catnip to attract the elusive jaguar to a camera point for filming. Upon attraction, the wild jaguar reacted in the exact same way that domestic cats react to catnip, suggesting further proof of the genetic existence of the susceptibility to catnip outside of domestic felines.

Catnip contains nepetalactone, a terpene. Nepetalactone can be extracted from catnip using steam distillation. Cats detect it through their olfactory epithelium and not through their vomeronasal organ. At the olfactory epithelium, the nepetalactone is hypothesized to bind to one or more olfactory receptors where it probably mimics a cat pheromone, such as the hypothetical feline facial pheromone or the cat urine odorant MMB.

Other plants that also have this effect on cats include valerian (Valeriana officinalis) and plants that contain actinidine or dihydroactinidiolide (Smith, 2005).

Species
Nepeta cataria (Catnip, True Catnip, Catmint or Field Balm) is a 50–100 cm tall herb resembling mint in appearance, with greyish-green leaves; the flowers are white, finely spotted with purple. It has been introduced to many countries, and is now a widespread weed in some areas, including the United States. A lemon-scented cultivar, N. cataria 'Citriodora' looks exactly like true catnip, but has the scent of lemons, and can be used like Lemon balm.

Nepeta grandiflora (Giant Catmint or Caucasus Catmint) is lusher than true catnip, and has dark green leaves and dark blue, almost purple flowers.

Nepeta × faassenii (N. racemosa × N. nepetella; Faassen's Nepeta or Faassen's Catnip) is mostly grown as an ornamental plant. This hybrid is far smaller than either of above and is almost a ground cover. It has greyish-green leaves and light purple flowers.

Some Dracocephalum, Glechoma and Calamintha species were formerly classified in Nepeta.

Nepeta species are used as food plants by the larvae of some Lepidoptera (butterfly and moth) species including Coleophora albitarsella.

Nepeta curviflora flowers
Selected speciesNepeta agrestis
Nepeta annua
Nepeta apuleii
Nepeta beltranii
Nepeta camphorata
Nepeta cataria
Nepeta ciliaris
Nepeta coerulescens
Nepeta curviflora
Nepeta densiflora
Nepeta dentata
Nepeta dirphya
Nepeta discolor
Nepeta elliptica
Nepeta everardi
Nepeta floccosa
Nepeta foliosa
Nepeta fordii
Nepeta glutinosa
Nepeta govaniana
Nepeta granatensis
Nepeta grandiflora
Nepeta heldreichii
Nepeta hemsleyana
Nepeta hindostana
Nepeta hispanica Nepeta italica
Nepeta jomdaensis
Nepeta kokamirica
Nepeta kokanica
Nepeta laevigata
Nepeta lamiopsis
Nepeta latifolia
Nepeta leucolaena
Nepeta leucophylla
Nepeta longibracteata
Nepeta manchuriensis
Nepeta melissifolia
Nepeta membranifolia
Nepeta micrantha
Nepeta multibracteata
Nepeta multifida
Nepeta mussinii
Nepeta nepalensis
Nepeta nepetella
Nepeta nervosa
Nepeta nuda
Nepeta parnassica
Nepeta parviflora
Nepeta phyllochlamys
Nepeta prattii
Nepeta pungens Nepeta racemosa
Nepeta raphanorhiza
Nepeta scordotis
Nepeta sessilis
Nepeta sibirica
Nepeta sibthorpii
Nepeta souliei
Nepeta spruneri
Nepeta staintonii
Nepeta stewartiana
Nepeta sungpanensis
Nepeta supina
Nepeta taxkorganica
Nepeta tenuiflora
Nepeta tenuifolia
Nepeta tuberosa
Nepeta ucranica
Nepeta veitchii
Nepeta virgata
Nepeta wilsonii
Nepeta yanthina
Nepeta zandaensis

Natural hybrids
Nepeta × faassenii


http://en.wikipedia.org/wiki/Catnip