| Home | E-mail | Cactuspedia | Mail Sale Catalogue | Links | Information | Search  |

 
 
 
Aestivation  [ Ecology - Botany ]
(
also: Estivation)  

Dictionary of botanic terminology - index of names

Synonyms: Summer rest, Growth Arrestment  or  Aestival dormancy
     
In plants and seeds the aestivation is a process for survival, a temporary cessation of growth or inactive phase during summer.
     
Aestivation (Summer dormancy) is a yearly cycle caused by chemical changes within plant cells. It is stimulated by unfavourable environmental condition with height temperatures, dryness and longer days in late spring and summer, plant metabolism comes to a virtual standstill. Summer dormancy is often found in tropical plant growing in arid areas. Plants store up water, nutritive elements and carbohydrates, which they can use to sustain themselves during dormancy.
With sparse rainfall Mother Nature has provided the plant with a built-in protection plan - dormancy. The plant will stop to grow as moisture reserves dry up, but it is far from dead.

During dormancy, stop watering and fertilizing. Let the leaves die back naturally and place the plant in a cool, shaded place while it goes through its dormancy period. Plants generally "sleep" for several month and start growing again only in Autumn when the temperature became cool an days shorten.
During prolonged summer cool and humid spells these plants are tricked into breaking dormancy and begin to swell too early. Yes hotter weather will arrest the swelling but the plants won’t return to summer normal size and makes them susceptible to damage from late prolonged drought and heat.
In general greater root mass means better access to water and nutrients, so plants are more tolerant of drought and can recover more rapidly from dormancy.
Conversely some indoor tropical plants are in constant growth and do not experience dormancy, so they require fertilizers and water all the time.
Plants who require pruning, should be eventually pruned in mid-summer at the end of their dormancy.


Seed aestivation (summer dormancy): Non-germination of seeds due to two dormancy factors. Seeds need to under go both a chemical and physical change. Many seeds germinate only after an extended period of dormancy. To break the summer dormancy and encourage germination of seeds when fall comes, and the rains begin, seeds must be exposed to cool temperatures.
 

 


Advertising



 

 

1


 
 
 
 
Holdfast roots  [ Botany  ]

Dictionary of botanic terminology - index of names

 
     
  Some species of climbing plants develop holdfast roots which help to support the vines on trees, walls, and rocks. By forcing their way into minute pores and crevices, they hold the plant firmly in place.  
     
Climbing plants, like the poison ivy (Toxicodendron radicans), Boston ivy (Parthenocissus tricuspidata), and trumpet creeper (Campsis radicans),  develop holdfast roots which help to support the vines on trees, walls, and rocks. By forcing their way into minute pores and crevices, they hold the plant firmly in place. Usually the Holdfast roots die at the end of the first season, but in some species they are perennial. In the tropics some of the large climbing plants have hold-fast roots by which they attach themselves, and long, cord-like roots that extend downward through the air and may lengthen and branch for several years until they strike the soil and become absorbent roots.

Major references and further lectures:
1) E. N. Transeau “General Botany” Discovery Publishing House, 1994
   

 

 

 

| Home | E-mail | Cactuspedia | Mail Sale Catalogue | Links | Information | Search  |