Kamis, 22 April 2010

GERMINATION


Germination

Growth is the number, size and volume of cells Irreversible.menekankan on quantity, while the development process of reaching maturity / adulthood individuals who do not speak the quantity but the quality of the cells.
to discuss how the growth can be seen in the events of germination (early growth), which ended with the growth mature flowering plants which are capable of producing fruit with seeds that make up individual seeds germinated kemudiaan flowering again.

PERKEBAMBAHAN

  • Germination of seed dormancy begins first with (stop the activity)
  • make the seed dormancy of dry conditions due to transpiration etc.
  • evaporation in the seeds of this event makes seeds increased osmotic pressure / high
  • because the state of dry beans so hipertonis with the watery environment then there imbibition
  • imbibition is the condition of water coming into the seed coat and seed volume increases
  • turgor pressure of growing beans make up, so there is an emphasis towards the outer seed coat increases
  • presence of water in the seeds also make the hormone abscisic Asan decreased while the hormone gibberellin levels in seeds become active and increase
  • Active gibberellins in seeds will be intensified to become active amylase enzyme
  • Amylase enzyme then hydrolyzes starch in food grain reserve (cotyledon). to glucose
  • presence of glucose menjadkan embryo / potential individuals to receive the food that stimulates cell division in actively engaging in mitosis as in the radicle tip on hypokotil, and plumulae in epicotyl
  • good growth potential due to the roots of (hypocotyl) and stem in part (epicotyl) will solve the pressing and seed coat that is soft due to high water turgor pressure
  • a result of that process munculah sprouts (prospective crop)
  • if germination was in a dark place it will be faster because the active auxin without light stimulate apical region grew faster (Etiolasi) but if no light will continue to die along with endless reserves of food to eat because food is not immediately replaced with the result of photosynthesis, if there is sunlight he is the active growing (so the story of germination),

What can be analyzed from the story above
  1. proved essential for seed dormancy
  2. then when we finished eating rambutan, we waste it the seeds will not grow? why because the seeds are still wet, still a lot of water so that it could not happen osmosis.
  3. Water in germination for what? it was not for photosynthesis, but to raise the turgor pressure, gibberellin activate, terminate dormancy
  4. So cotyledons function as food reserves in the seed. During the development of plant seeds, the cotyledon was as a storehouse of food when germination, the cotyledon which contains a lot of these foods continue to be used when the institutions forming organs organs, once formed organs, eg plumulae has become a true leaves then stopped taking food because it occurs in the cotyledon photosynthesis..

There are 2 types of germination based on the growth rate of epicotyl and cotyledon hypokotilnya and location of land growing
  1. Epigeal: if growth is faster than the epicotyl hypokotil cotyledons raised above the ground so often called epigeous
  2. Hypogeal: if growth is faster than hypokotil epicotyl, this causes the position of cotyledons remain below ground soil is often referred Hypogeous

epicotyl that existing institutions above kottiledon who later formed leaves plumulae candidate, was hypokotil that existing institutions under which it will be as radicle cotyledons root candidates.



Treatment experiments in this case hypogeal epigeal, and we can do is very simple:
  • to sow the seeds about an inch into the soil in pots.
  • Keep in a sunny location with warm temperatures and adequate moisture in the pot so that soil does not dry out.
  • Sprouts will appear within two weeks.
  • When the seedlings have true leaves, and the complete organ organs.
  • Observe categorized epigeal seedling growth or hypogeal

Notice how the cotyledon in seeds Honeylocust , and Kentucky coffeeree 

  • Honeylocust seeds was stuck into the ground cotyledon, epicotyl position to grow faster than hypokotil, above the cotyledons are soft and green leaves.
  • Leaves were able to perform photosynthesis in the light.
  • Seeds of Kentucky coffeeree on cotyledons remain in the soil and the great white.
  • Roots in Kentucky grew faster coffeetree
  • Lots of food reserves in the cotyledons were transferred to the roots even before they appear on the ground.
  • This is one reason it takes longer to see the emergence of shoots in Kentucky honeylocust coffeetree compared to the soil surface.
At the time of seed began to germinate in the embryo meristem tissue continues to grow and expand the network to produce a new network whose task is different (defrensiasi and Specialisation) that eventually form the organs grow roots stems and leaves form the next development will grow flowers and fruit seed tubers may, where fruit and flowers are the result of modification stems and leaves.
after the young plants are formed subsequent growth is determined by the activity of meristem tissue in growing points that led to prolongation.

1 komentar:

  1. 好文章就值得回響,如果可以常常看到您的更新,應該是件很幸福的事情~~ ........................................

    BalasHapus