Growing Point

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Growing Point

 

the rounded cone-shaped tip of a growing axial organ of a plant (stem or root), which consists of formative tissue (meristem). In algae, mosses, ferns, and horsetails the growing point consists of a single initial cell; in club mosses and seed plants it is made up of groups of initial cells placed in layers parallel to the surface of the organ. As a result of the division of these cells, the corpus, a mass of cells enclosed by a dome-shaped tunica, is formed. The cells of the corpus divide in various directions (volume growth), and the cells of the tunica divide predominantly perpendicularly (surface growth). It is by this process that plant growth occurs.

The growing point is sometimes called the apex, and its terminal cells are known as apical cells. The cells of the growing point that lie at its very tip, which are often designated as the promeri-stem, are converted lower on the axis into the meristem, from which true tissues are formed. At some distance from the tip of the growing point of the stem, or shoot apex, rudimentary leaves arise exogenously in the form of surface nodules. Buds are subsequently formed in the axils of these leaves. The young leaves and the shoot apex form the axillary bud. Between the rudimentary leaves there are zones of intercalary growth, which cause the shoot apex to grow. The growing point of a root, or the root apex, lacks surface appendages and is covered with a rootcap.

O. N. CHISTIAKOVA

References in periodicals archive ?
Those with two noses have two growing points and could produce two flowers next spring or certainly by the following year.
Rhizomes (bearded iris, Japanese iris) have thickened stems with a primary growth point at one end and additional growing points along the sides.
If you buy tubers, plant them about three times as deep as they are wide, but since there are roots and growing points (buds) all over, there is no ``up'' or ``down'' like there is with tulip or daffodil bulbs.
There are more growing points and less chance of them all being attacked by wilt.
Remove the growing points from early peas which have finished flowering to concentrate energies on pod production.
I'd also want to see a steady flow of international players because that's one of the true growing points of this league.
10 Look in growing points and under leaves on plants for greenfly or whitefly - and spray at the earliest opportunity.
Check the growing points and undersides of young leaves and spray with a suitable insecticide.
2Try putting three or four bushy surfinias in a 14-inch hanging basket, grow on in a warm place and keep pinching out the growing points after two sets of new leaves come through.
Saracens, meanwhile, have obviously benefited from the addition of South African stand-off Luke Smith to their ranks, adding five penalties and a conversion to his growing points tally.
Pinch out growing points to encourage bushier plants.
5Remove the growing points from indoor tomatoes that have reached ultimate cropping height.