An Eco-sustainable World
Ecological Glossary

Sympodial

Sympodial

With the term sympodial, in botany, we refer to a type of ramification in which the main axis has definite growth (therefore destined to stop) and laterally produces first, second, third order branches, etc.; in this case the growth occurs in an increasing manner in the following branches, so the third-order branch will be longer than the second-order one.
There is sympodial growth also in some types of inflorescence, called cymoses, defined or branchial, which have a main axis that ends with a flower, under which new axes are formed with new terminal flowers.
Sympodial growth also occurs when the apical bud degenerates at a certain point (sometimes for the formation of a flower) and its function is taken over by the underlying buds.
The sympodial growth process can occur either after each growth period or after a certain number of leaves, depending on the plant.
If the function of the apical bud is assumed by the two lateral buds immediately below, these will give rise to two lateral branches, defined as first order. Thus in the following growth cycle, the apical buds will degenerate and other branches will originate (called second, third order and so on) whose growth is gradually greater in the following branches, so the third order branch will be longer than second order, and so on.
In this case the growth is defined as sympodial a dicasio.

If, on the other hand, the elongation of the cauline apex is carried out only by the bud closest to the aborted apical one, the type of branching will be called sympodial to monocasium. The new bud will stretch towards the main stem, and at first sight it is not seen that they are two distinct branches.
In the case of the sympodial growth of the inflorescences, however, these can be divided into two types:
– Monocase growth (also called uniparous top); in this case the inflorescence is formed by various flowers positioned on a single axis, in which this produces a single secondary branch which in turn also produces a single branch and so on. In this type of development the growth is zig-zag and ends in a flower. In turn, this growth is distinguished in helicoid if the secondary branches are all formed on the same side of the main axis, while it is defined as scorpioid if the branches develop alternately to resemble a scorpion’s tail.
– Growth in dicasio (also called bipara top); in this case the inflorescence will be such that, under the terminal flower, two symmetrical secondary floriferous branches develop which continue to grow and divide, eventually forming other flowers anyway.
– Finally a pleiocasio (also called umbrella-shaped top or multiparous top); in the latter case in the inflorescence, under the apical flower, more than two branches sprout which continue to grow and divide, eventually forming flowers anyway.




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