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Flower
spathe
Sheets
Pseudobulbs
bracts
roots
Rhizome
Parts of an Orchid
Sheets
It is on the leaves that the orchid produces most of the energy that the plant needs. In fact, this is a capacity of all the green parts of the plant. It is through the leaf that transpiration takes place, gas exchange, capturing sunlight to carry out photosynthesis and also the possibility of absorbing nutrients.
The figure below shows the complex structure of a leaf.
Cuticle - is a mechanical barrier formed by fatty acids (fats), protecting against excessive water loss, fungal and bacterial attacks and mechanical trauma. The cuticle is thinnest at the bottom.
Epidermis - is the most colorless, outermost layer of the leaf (top and bottom). It is responsible for controlling perspiration, regulating gas exchange, defending against infections, secreting metabolic compounds, and absorbing water and nutrients. At the bottom, this layer had pores specialized in gas exchange called stomata.
mesophile - Comprises the tissue between the two epidermis. Chloroplasts are found in the mesophyll, structures full of chloriphyll responsible for photosynthesis. This tissue is traversed by conduction beams (visually represented by the leaf's veins). The conduction vessels are of two types, the xylem, responsible for bringing nutrients from the soil to the leaves, and the phloem, responsible for conducting the organic molecules produced in the leaves to the rest of the plant. In orchids, in fact, there is no separation of palisade and spongy parenchyma, the latter being homogeneous throughout its structure.
stomata - They are the most important organs for gas exchange in orchids, present on the underside of the leaves. The stomatal cells are the only ones in the epidermis that have chlorophyll, therefore capable of carrying out photosynthesis. The stomata are also responsible for most of the foliar fertilization. In the figure on the side we also see the stomatal chamber which, in orchids, is kept filled with humid air, an important adaptation that reduces 136bad5cf58d_water for the environment.
pseudobulbs
They are usually referred to as bulbs, although this is not the correct nomenclature. They are characterized by being thickened, with an adapted function for water storage and regulation of carbohydrate metabolism. The shape of the pseudobulb is different among different species of orchids. It is one of the main adaptations that allows orchids to survive prolonged periods of drought. The observation of this structure allows the orchidist to evaluate if the irrigation regime of his plants is adequate or not; as they become more furrowed, they indicate a lack of irrigation. The maximum absorption capacity of nutrients occurs when they are swollen (full of water). They should never be cut after flowering.
Rhizome
the axis of growth of the orchid and one of the most important structures of the plant. It is the true stem of the sympoidal orchid (modified stem). It contains the buds, responsible for the formation of buds that will evolve into pseudo-bulbs. It is the rhizome that can be cut to obtain new orchid seedlings.
In orchids with so-called monopoidal growth, there is no rhizome.
roots
the structure responsible for fixing the plant to the substrate and also for absorbing water and nutrients.
Nas orquídeas as raízes tem cor esbranquiçada e se torna esverdeada quando cheias de água . They are structurally adapted, being surrounded by a sponge, called a canopy, thus being able to absorb the moisture present in the air.
The tip is greenish, and may have some other pigment. This structure is very sensitive, drying out when touched with some force, irrigated with highly concentrated solutions of fertilizers or pesticides or even if attacked by pathogens. If the tip is not greenish, the root is no longer growing.
Observar as condições das raízes sempre allows a good conclusion about the health of your orchid.
Flower
It is the reproductive structure of the flower. Every beautiful flower presentation has the function of attracting its pollinators to fertilize it to form seeds and perpetuate the species.
The flower buds developing inside the spatha (bracts), which protects them from weather and also from predators. As the buds develop, they reach the external environment to finalize maturation, culminating in the opening of the flower.
The flower of an orchid is always formed by three sepals and three petals, in which one of the petals is modified lip. Technically, the sepals protect the orchid's reproductive organs and the petals attract pollinators.
spathe
The reproductive part of the orchid is divided into a column (gynostemium), anther, stigma and ovary.
The column is formed by the male (Antera) and female (stigma) organs. The pollinae are protected inside the anther, which are responsible for fertilization when they are moved (pollinator function) to the stigma. As an extension of the column, at the back of the flower are the ovaries, in which the maturation of the seeds will occur if fertilization occurs (capsule).
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