sensitive plant

Mimosa pudica
(Mimosa pudica) Flower-head
Scientific classification
Kingdom: Plantae Division: Magnoliophyta Class: Magnoliopsida Order: Fabales Family: Fabaceae Subfamily: Mimosoideae Genus: Mimosa Species: M. pudica
Binomial name
Mimosa pudica L.[1]

Mimosa pudica (Sensitive Plant) (pudica = shy), is a creeping annual or perennial herb often grown for its curiosity value: the compound leaves fold inward and droop when touched, re-opening within minutes. The species is native to South America and Central America, but is now a pantropical weed.

Contents 1 Description 1.1 Plant movement 2 Taxonomy and nomenclature 2.1 Common names 3 Distribution 4 Agricultural impacts 5 Cultivation 6 Uses 6.1 Medicinal properties 6.2 Ayurvedan Properties (guna) of Lajjalu 7 See also 8 References 9 External links

Description

The stem is erect in young plants, but becomes creeping or trailing with age. The stem is slender, branching, and sparsely to densely prickly, growing to a length of 1.5 m (5 ft). The leaves of the mimosa pudica are compound leaves. The leaves are bipinnately compound, with one or two pinnae pairs, and 10-26 leaflets per pinna. The petioles are also prickly. Pedunculate (stalked) pale pink or purple flower heads arise from the leaf axils. The globose to ovoid heads are 8-10 mm in diameter (excluding the stamens). On close examination, it is seen that the floret petals are red in their upper part and the filaments are pink to lavender. The fruit consists of clusters of 2-8 pods from 1-2 cm long each, these prickly on the margins. The pods break into 2-5 segments and contain pale brown seeds some 2.5 mm long. The flowers are pollinated by the wind and insects.^[2]

Plant movement

Mimosa pudica is well known for its rapid plant movement. In the evening the leaflets will fold together and the whole leaf droops downward. It then re-opens at sunrise. This type of motion has been coined thigmonasty movement. The leaves also close up under various other stimuli, such as touching, warming, blowing, or shaking. The stimulus can also be transmitted to neighbouring leaves. These types of movements have been termed seismonastic movements. The movement is caused when the leafs lose turgor pressure. Turgor pressure is the force that is applied onto the cell wall by water and other cell contents. This allows the plant to stay upright. But when it is disturbed by a stimulus, chemicals in the plant force the water to leave the cell. When this pressure is lost the result is a sagging plant. This characteristic is quite common within the Mimosaceae family.

It is not known exactly why Mimosa pudica evolved this trait, but many scientists think that the plant uses its ability to shrink as a defense from predators. Animals may be afraid of such a fast moving plant and would rather go and eat a less active one.

Taxonomy and nomenclature

Mimosa pudica was first formally described by Carl Linnaeus in Species Plantarum in 1753.^[3] The species epithet, pudica, is Latin for "bashful" or "shrinking", alluding to its shrinking reaction to contact.

Common names

The species is known by numerous common names including

• sensitive plant^[4]
• humble plant^[4]
• shameful plant^[4]
• sleeping grass^[5]
• shy plant
• shrinking plant
• humble plant
• modest plant
• moriviví
• touch-me-not^[4].
• küstüm (Turkish)
• Kruikie roer my nie (Afrikaans)
• chui mui (Hindi)

The Chinese name for this plant (Chinese: 含羞草; pinyin: hánxiū cǎo) translates to "shyness grass".^[6] Its Sinhala name is Nidikumba, where 'nidi' means 'sleep'^[7]. Its Tamil name is Thottal Sinungi, where 'Thottal' means 'touched' and 'Sinungi' means 'little cry'^[8]. Other non-English common names include Makahiya (Philippines, with maka- meaning "quite" or "tendency to be", and -hiya meaning "shy", or "shyness")^{[citation needed]}, Mori Vivi^[9] (West Indies), and mate-loi (false death)^{[citation needed]} (Tonga). In Urdu it is known as CHui-Mui. In Bengali, this is known as 'Lojjaboti', the shy virgin. In Indonesia, it is known as Putri Malu (Shy Princess).

Distribution

Mimosa pudica is native to South America and Central America. It has been introduced to many other regions and is regarded as an invasive species in Tanzania, South Asia and South East Asia and many Pacific Islands.^[5] It is regarded as invasive in parts of Australia and is a declared weed in the Northern Territory,^[10] and Western Australia although not naturalized there.^[11] Control is recommended in Queensland.^[12] It has also been introduced to Nigeria, Seychelles, Mauritius and East Asia but is not regarded as invasive in those places.^[5] It also grows in parts of Florida, in the United States of America.

Agricultural impacts

The species can be a troublesome weed in tropical crops, particularly when fields are hand cultivated. Crops it tends to affect are corn, coconuts, tomatoes, cotton, coffee, bananas, soybeans, papaya, and sugar cane. Dry thickets may become a fire hazard.^[2] In some cases it has become a forage plant although the variety in Hawaii is reported to be toxic to livestock.^[2][13]

Mimosa pudica also has the ability to take nitrogen from the air and "fix" it to a form that is suitable for itself and other plants. This trait is common among plants in the Fabaceae family.

Cultivation

In cultivation, this plant is most often grown as an indoor annual, but is also grown for groundcover. Propagation is generally by seed.

Uses

Mimosa pudica is sold as an educational product and novelty gift sometimes under the trademark name TickleMe Plant.^[14]

Medicinal properties

The plant lajjalu described in Ayurveda has been identified as Mimosa pudica.^{[dubious – discuss]} This plant has several alternate Sanskrit common names, including Namaskari, and Rakta Paadi.^{[citation needed]}

In Ayurveda, the plant is described as a plant which folds itself when touched and spreads its leaves once again after a while. It is said to have a bitter and astringent taste, and has a history of use for the treatment of various ailments. Most commonly used is the root, but leaves, flowers, bark, and fruit can also be implemented.^{[citation needed]}

A list of some of the notable chemical compounds found in Mimosa pudica can be found here: [1].

Ayurvedan Properties (guna) of Lajjalu

• Has tikta and kashaya rasa (bitter and astringent taste).^{[citation needed]}
• Has property of cold (sheetha).^{[citation needed]}
• Balances kapha, pitta.^{[citation needed]}
• Shushrutha has placed this plant in Priyangwambhastaadi gana.^{[citation needed]}

Mimosa pudica with leaves open

Mimosa pudica with leaves closed

See also

• Exotic plants
• Mimosa pigra

References

External links

Wikimedia Commons has media related to: Mimosa pudica

• View occurrences of Mimosa pudica in the Biodiversity Heritage Library
• Sensitive Plant by Dr. T. Ombrello
• Nyctinasty and Mimosa leaf movement by John Hewitson
• Video of Mimosa reacts when touched
• Videos of the sensitive plant 1 2
• Streaming video of plant. [2]
• Video mimosa pudica in Bornéo [3]