The Green Living World
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continually renewed and a series of cells are produced. Meristems are
divided into two types: a) the primary, mainly derived from the embryo,
which are responsible for the tissue architecture of herbs and for the primary
structure of any plant; and b) the secondary, which, when present, contains
the tissue from which the production of plant secondary structure derives,
including most wood and additional functional parts.
In the meristem, the produced cells, at first indeterminate, follow their
destiny until maturity, achieving different shapes and displaying different
activities in accordance with their position in the pertinent organ. Thanks to
meristems, the plant grows, changes, and renews itself. Even when the plant
is not growing, the meristems are still present and active. Thanks to these
cells, in temperate zones each year in spring, perennial plants restart their
lives, generating new tissues, since meristems elaborate the body of plants
according to the environmental conditions and the plant’s development
plan.
Apical meristems produce the primary tissues forming the so-called primary
plant body. Both root and shoot apical meristems are composed of little
delicate cells. In particular, the root apical meristems, moving through the
soil, must be protected by the root cap. Many herbaceous plants undergo
only primary growth, whereas others, like woody plants, experience a
secondary growth, which is accomplished mainly by lateral meristems.
Tissues formed by these new meristems are responsible for most of the plant
body, including the trunk, branches, older roots of trees, and shrubs, and are
collectively called the secondary plant body, compared to the primary one
now limited to its innermost parts and derived from the first step of plant
growth from the plantula.
The potential of meristems has not been ignored by the nutraceuticals sector.
Among botanicals, the most innovative products, like those utilised in
meristemotherapy, deserve special attention. The utilisation of meristems
possesses a special appeal, derived from the therapeutic use of buds or other
young and developing vegetal parts. The general idea is to profit from the
renewing force of growing or of newborn parts of the plant. Nowadays, this
is reported in the new approach based on botanicals focused on the use of
juvenile parts, named in several ways, e.g. bud-, meristematic-, embryo-,
phytoembryo-, or blasto-therapy, among others. For the sake of simplicity,
we will adopt the terms gemmotherapy or meristemotherapy, referring to a
modern non-conventional medical therapy, using plant raw materials rich in
meristems to obtain bud-derived products. Despite an increase in public
interest and requests, gemmotherapy is still in search of its proper definition,