Thigmo-

Thigmomorphogenesis is the response by plants to mechanical sensation ( wind, raindrops, rubbing by passing animals, etc ) by altering their growth patterns, which may include their canopy structure, growth rate, anatomy, morphology and mechanical strength of their wood. 

Thigmotropism is a movement in which a plant moves or grows in response to touch or contact stimuli, such as wall, pot, or trellis, etc.

Thigmonasty or seismonasty is the nastic response of a plant to touch or vibration.

Thigmotaxis is the movement of an organism toward or away from objects that provide a mechanical stimulus.

Thigmomorphogenesis

Thigmomorphogenesis is from the Greek words “thigma” which means ‘to touch’;  “morphê” shape and “genesis” creation.  Thus, thigmomorphogenesis is the response by plants to mechanical sensation by altering their growth patterns, which may include their canopy structure, growth rate, anatomy, morphology and mechanical strength of their wood.  The mechanical sensation can be evinced by wind, raindrops, and rubbing by passing animals.

The term ‘thigmomorphogenesis’ was first coined by Mordecai J. Jaffe. ¹

Plant responses to mechanical sensation through reduction in the rate of stem elongation, increase of stem diameter resulting in shorter and stockier plants.  Other responses include alterations in chlorophyll content, hormone levels, biotic and abiotic stress resistance, pithiness, flowering time, senescence, and stomata aperture. ²

1. Lansing Funeral Home, 2007, The Lansing Star Online Obituaries, 14^th October, L-Star Publishing, Inc,  NY.   http://www.lansingstar.com/obituaries/3020-mordecai-j-qmarkq-jaffe

2. Biddington NL.1986,  The Effects of Mechanically-Induced Stress in Plants : A Review. Plant Growth Regulation 1986;4:103-123.

Observations & Studies

Theophrastus, a Greek who succeeded Aristotle in the Peripatetic school, observed that trees growing in windy environments were shorted in heights, shorter internodes, more knots, less straights, closer grain, and harder wood.¹

Charles Darwin reported a mechono-stimulus-induced plant behaviour, where roots reorient their growth direction upon making contact with barriers. ²

Free-swaying Pinus radiata trees grew more in diameter over the lower part of the trunk than stayed trees.³

Salisbury reported that repeated touching of leaves of young cocklebur plants caused a 30% inhibition in growth in addition to an increase in rate of leaf senescence. ⁴

Moderate shaking of Liquidambar trunks for 30 seconds daily reduced height growth to only 20 to 30 percent of that of trees not shaken.⁵

Young plants of Hordeum vulgare, Bryonia dioica, Cucumis sativus, Phaseolus vulgaris, Mimosa pudica and Ricinus communis show retardation of growth when given mechanical stimulus. ⁶

  

1. Theophrastus, 300 BCE, De Causis Plantarum (On the Causes of Plants)

2. Darwin & Darwin, 1881, The Power of Movement in Plants 

3. Jacobs, MR., 1954, The effect of wind sway on the form and development of Pinus radiata D. Don, Australian Journal of Botany 2(1) 35 - 51

4. Salisbury FB, 1963, The Flowering Process, New York, Macmillan.

5. Neel PL, Harris RW., 1971, Motion-induced inhibition of elongation and induction of dormancy in Liquidambar. Science. 1971 Jul 2;173(3991):58-9.

6. Jaffe MJ, 1973,  Thigmomorphogenesis  : The Response of Plant Growth and Development to Mechanical Stimulation : With Special Reference to Bryonia dioica ., Planta 1973 Jun ; 114(2):145-57. Doi:10.1007/BF000387472, 

Summary of structural changes in acclimation to windy environments :

 Anatomy

·         Increase in MFA

·         Increase in grain angle

·         Increase in cell division in direction of flexing

·         Increase in wood density

·         Increase in lignification ( higher S:G )

·         Decrease in stiffness, more flexible

Morphology

·         Shorter thicker stems ( Lower H:D )

·         Smaller leaves

·         Shorter internodes

·         Shorter branches

·         Thicker branch junctions

·         Streamlining

Sarikei : Local Produce

Engkabang besar

Shorea macrophylla

Engkabang kechil

Plukenetia corniculata

buah empit

Pentaspodon motleyi

berangan tikus

Castanopsis borneensis

sagan berauh

Scorodocarpus borneensis

Passiflora foetida

Royal Family of Palms

Royal Palm

Scientific name : Roystonea regia

Synonyms : Euterpe ventricosa, Euterpe jenmanii , Oreodoxa regia, Oenocarpus regius, Palma elata , R. floridana, R. jenmanii, R. elata, R. ventricosa, R. regia var. hondurensis

Common names : Cuban royal palm, Florida royal palm, Royal palm

Native : Southern Florida, Mexico, Central America, and the Caribbean





Caribbean Royal Palm

Scientific name : Roystonea olearcea

Synonyms : Areca oleracea, Euterpe caribaea, Gorgasia oleracea,  Kentia oleracea , Oreodoxa oleracea, Oreodoxa caribaea, R. caribaea, Oreodoxa regia var. jenmanii, R. oleracea var. excelsior, R. venezuelana, R. oleracea var. jenmanii

Common names : palmiste, imperial palm, cabbage palm

Native : Lesser Antilles, Columbia, Venezuela, Trinidad and Tobago.

Dwarf Royal Palm

Scientific name : Adonidia merrillii

Synonyms : Normanbya merrillii, Veitchia merrillii

Common names : Manila palm, Christmas palm

Native : The Philippines, Sabah 

Pinang Rajah

Scientific name : Cyrtostachys renda

Synonyms : Areca erythrocarpa, A. erythropoda, Cyrtostachys lakka, C. rendah, C. lacca var singaporensis, C. lakka, Pinanga purpurea, Ptychosperma coccinea

Common names : Pinang rajah, red palm, red sealing wax palm, lipstick palm

Native : Thailand, Malaya, Sumatra, Borneo

King Palm

Scientific name : Archontophoenix alexandrae

Synonyms :  Cocos romanzofiana, C. australis, C. plumose, C. datil, C. geriba, C. arechavaletana, Calappa acrocomioides, Calappa australis, Calappa datil, Calappa plumose, Calappa romanzoffiana.

Common names : Alexander palm, King palm

Native : Queensland & NSW

Queen Palm

Scientific name : Syagrus romanzoffiana

Synonyms : Ptychosperma alexandrae

Common names : Queen palm, Cocos plam

Native : Paraguay, Argentina, Brazil, Bolivia

Princess Palm

Scientific name : Dicyosperma album

Synonyms : Areca alba, A. borbonica, A. lacteal, A. propria, A. purpurea, A. furfuracea, A. rubra, A. pisifera, A. aurea, Dictyosperma aureum, D. furfuraceum, D. rubrum, Linoma alba, Sublimia palmicaulis.

Common names : Princess palm, hurricane palm

Native : Mascarene Islands

Landscape Guidelines @ Malaysian Authorities

Publications by Jabatan Landskap Negara :

    Garis Panduan Negara Edisi 2
    National Landsape Policy
    Manual Pelan Induk Landskap
    Panduan Penanaman Pokok Teduhan
    Panduan Rekabentuk Sejagat Kemudahan Rekreasi Taman Awam 

Guidelines by Jabatan Perancangan Bandar & Desa Malaya :

    Garis Panduan Perancangan 005-A Tanah Lapang & Rekreasi ( draft )
    Garis Panduan Perancangan 014-A Taman Atas Bumbung
    Garis Panduan Perancangan 022-A Gated Community & Guarded Neighbourhood
    Garis Panduan Perancangan 024-A Kejiranan Hijau
     

Landscape Guidelines for respective Local Authorities :

    Kemaman

    Klang
    Kota Bharu
    Kuantan
    Kubang Pasu
    Nilai 
    Selayang
 

Cute Ornamental Plants

Species : Pachira aquatica

Synonyms : Carolinea macrocarpa, Bombax macrocarpum, B. glabrum, P. macrocarpa, etc

Common names : Malabar chestnut, Guina chestnut, provision tree, saba nut, 發財樹, 美國花生, 瓜栗, etc

Family : Malvaceae

Species : Tillandsia usneoides

Synonyms : Dendropogon usneoides, Renealmia usenoides, T. crinite, T. Filiformis, T. trichoides, etc

Common names : Spanish moss

Family : Bromeliaceae

Species : Tillandsia bergeri

Family : Bromeliaceae

Species : Dischidia ruscifolia

Common names : million hearts, etc

Family : Apocynaceae

Parthenium hysterophorus

Parthenium hysterophorus is a species of flowering plant in the aster family, Asteraceae.   Originated from the American tropics, it is now spread all over the world.  It invades all disturbed land, including farms & plantation, pastures, roadsides, park and gardens in India, Australia, Africa and Asia.

Biology

P. hysterophorus is an annual plant of the Asteraceae family. It normally grows to 30-90 cm in height, but can grow up to 1.5-2.5 m.   It occurs in humid and subhumid tropics, capable to grow on a wide variety of soil types

Flower heads are both terminal and axillary, penduculate and slightly hairy; composed of many florets formed into small white capitula, 3-5 mm in diameter.  Each head consists of 5 -8 fertile ray florets and about 40 male florets.  First capitulum forms in the terminal leaf axil, with subsequent capitula occurring progressively down to stem on lateral branches arising from the axils of the lower leaves.  Thousands of inflorescences may be produced at the apex of the plant during the season.

  

Seeds are black, flattened, about 2 mm long.  A plant can produce about 15,000-25,000 seeds.  Seeds buried in soil can remain viable for at least 4-6 years.  Germination occurred at 10-25°C, over wide range of soil pH.  Germination rate is extremely high.

 

Flowering may begin as early as 4 weeks after germination.  Life circle is about 86 days under optimum conditions, up to 335 days under unfavourable conditions.

Physiological studies have shown that P. hysterophorus has a low photorespiratory activity and has the C3 photosynthetic pathway but with positive C4 tendencies.

Its wide adaptability, photo- and thermo-insensitivity, drought tolerance, strong competition, allelopathy, high seed production, longevity of seeds in soil, small and light seeds that are capable of long distance travel via wind, water, birds, vehicles, machinery, contribute to its rapid introduction worldwide.

Noxious Weed

Parthenium hysterophorus is a vigorous weed that colonises pastures and farms.  Its presence reduce the pasture and crop production, as well as threatening the local biodiversity.

The presence of P. hysterophorus pollen grains inhibits fruit set in tomato, brinjal, bean, etc.

It found its way to India in the 1950s via contaminated wheat imported from the USA.  Today, approximately 2million hectares of land in India have been infested with P. hysterophorus.

P. hysterophorus was introduced to Australia via the movement of military aircraft and machinery during WW2 and pasture seeds.   In Queensland, it is declared a Class 2 plant under the Land Protection (Pest and Stock Route Management) Act 2002.

Health Hazard

P. hysterophorus is linked with several health problems, both in human and domesticated animals.

Contact with P. hysterophorus causes dermatitis and allergic respiratory problems in humans and cattle, due to the presence of toxin parthenin. 

Livestock fed on grass mixed with its leaves too will develop deteriorated quality of milk and meat.

It also causes diarrhoea, severe popular erythematous eruptions, breathlessness and choking.

Benefit

P. hysterophorus is used in its native neotropics as herbal remedy for various intestinal and skin disorders.  It has potential medicinal properties for skin inflammation, rheumatic pain, diarrhoea, urinary tract infections, dysentery, malaria and neuralgia.

Compost produce from P. hysterophorus can lower weed population, possibly due to allelophatic compounds present in it.  The allelophatic substances may be used as insecticide, herbicide, fungicide and nematicide.

Removal of heavy metal and dye from the environment.

Control

Chemical control with glyphosate has found to be unsuccessful.  Paraquat is effective only when the plant is young.  Manual removal can only be done when the population is small.

 

Biological control by leaf-feeding beetle from Mexico, Zygograma bicolorata is reported to be able to defoliate and kill the plant.