Orchid is one of the oldest cultures on Earth. Plants of this species appeared about 100 million years ago. Among horsetails and ferns, they became the first flowering crop. It is noteworthy that the appearance and structure of the orchid has been preserved since those ancient times. An unusual form of inflorescences, strong foliage and an airy root system have reached the present. In this article we will consider the features and structure of orchids.
General description of the species
Orchidaceae is one of the largest families in the plant world. Most of it is perennial grasses. More rare are shrubs and tree creepers. An orchid can have a wide variety of sizes. The smallest member of the family has a height of only a few centimeters, and the largest exceeds 35 meters.
Most representatives of this culture are epiphytes. They grow on the trunks of other plants, using them as a support. It is noteworthy that at the same time such orchids are not parasites. The soil is indifferent to this type of plants, they receive more sunshine and are less exposed to herbivores.
The roots of this ancient plant are one of its most important organs. They perform a number of functions necessary for the normal existence of an orchid. First of all, they allow the stems of the plant to become fixed in the substrate. Due to this, they are in an upright position. The second important point is the participation of the root system in the process of photosynthesis. Due to the structure of the orchid, they share this role with foliage. The third interesting feature of the roots of these plants is their ability to absorb moisture in the air and bark of the crops on which the orchid grows.
Another significantly common type of orchid is called lithophytes. Compared to epiphytes, they are few in number. Typically, such orchids grow in rocky terrain. The third group is terrestrial species. They are the second most species.
Orchid trunk can have a variety of shapes. It is short, long, erect, and creeping. It depends on the type of orchid plant, structure and its species characteristics. The culture has simple alternate leaves. The color of flowers can be very diverse, as well as their size. Experts distinguish two types of inflorescences from an orchid: a simple ear with a single arrangement of flowers and a brush with many flowers growing along the stem.
Branching Varieties
A large family of orchids can be divided according to the type of branching into two huge groups. The first species, developing horizontally, but releasing several stems that grow vertically, is called sympodial. Such a variety of orchids include Cattleya, Bulbofilyum, Oncidium, Encyclia and many others. The stem of these plants grows horizontally and in most cases is under the substrate. It releases to the surface a large number of vertically growing shoots. They, in turn, develop flowers, bulbs and other parts of the culture. It is noteworthy that such an orchid has a kind of main horizontal shoot. It is called a rhizome.
The second type of orchids are plants that have a monopodial shoot. Unlike the sympodial one, it has one growth point and it grows vertically. The most prominent representatives of this species are: Wanda, Erangis, Phalaenopsis and Vanilla. But besides them there are many more orchids of this type, growing in the wild. The structure of the orchid provides for the only main shoot on which the crown bud is located. From it annually grow new pairs of leaves. Between the leaves there are sinuses where the generative buds are located. They subsequently develop into an aerial root system and peduncles. It is noteworthy that the stem itself can also have buds. However, they are vegetative. Their role is to develop new shoots if the main stem dies.
Orchid Leaf Structure
Foliage of a plant can have a variety of shapes and sizes. It depends on the type. For example, in monopodial orchids, the leaves have large sizes and a dense structure. Under natural conditions, they play the role of a store of useful trace elements and moisture. Leaves are annually formed from shoots. Each shoot develops in two leaves. They grow strictly opposite each other. Specialists call them pairs. It is noteworthy that the distance between the leaves in pairs can be very different. In some cases, it can be several millimeters, and in others such a gap reaches a meter or more. This feature depends on the type of orchid.
In turn, in sympodial types, bulbs are responsible for the accumulation of nutrients. They are small formations located at the base of the shoot. In this regard, sympodial orchids have small, thin leaves of a narrow shape. Depending on the variety, they can be small scaly and long lashy.
Stem
Orchid has no stem in the full sense of the word. She has the role of escape. At the same time, the structure of the orchid shoot contributes to the rapid development of culture. In monopodial species, it is vertical; branches and leaves are located on it. Sympodial orchids have vertical shoots with branches of a rhizome or, as it is also called, rhizomes. This is the bearing part of the plant, its stem. Using epiphytic roots, the rhizome is attached to the substrate. It is noteworthy that the stems of this culture can be both short and very long. In the natural environment, plants of this family with a long trunk are attached to the trees by aerial roots. When growing orchids at home, a support is placed in a flower pot.
Root system
The structure of the root of the orchid varies depending on its type. Sympodial processes have processes that form on the bottom of the shoot. Monopodial differ in that they form roots along the entire length of the stem. However, although the location of the processes of different species is different, they perform the same functions. With their help, the orchid is attached to the substrate, absorbs moisture and nutrients.
Aerial Orchid Roots
These organs are the most unique part of the plant. Orchid is an epiphyte. Such plants attach to other crops by shoots, but are not parasites. They do not suck out nutrients, but simply rely on the plant. Orchids need this, for example, in order to get through the branches of trees to more illuminated places. The most striking representative of epiphytes is the Phalaenopsis orchid, the structure and size of which allows it to be grown at home. It is noteworthy that plants do not root in the ground. They get all the substances necessary for the normal development through photosynthesis. They are able to take moisture directly from the air. It is to perform these functions that they need roots located on the surface. In shape, they are long and thick processes. The outer layer of roots consists of velamen. This is a kind of spongy tissue. With its help, the roots absorb moisture in the air. In addition, such a coating has a protective role.
Bulbs
This interesting name was given to the special formations that are found only in sympodial orchids. They are a thick powerful shoot that acts as a reservoir for moisture and nutrients. Moreover, the word "bulb" in translation from Latin means "onion". It is noteworthy that, in addition to such an education, there are so-called pseudobulbs. They are the same growths, performing the same role, but having a different appearance. Pseudobulbs can be ovoid, oval and even conical. However, both types have a common name - tuberidium. They emerge from the vegetative shoots of rhizomes. In fact, bulbs are shoots of a special shape. They also form buds and form leaves.
Orchid flowers
With all its variety of shapes and colors, the structure of the orchid flower is quite simple. Its distinctive feature is central symmetry, that is, six parts are arranged in two circles. The outer circle has three colored sepals. They, in turn, alternate with the petals of the inner circle. In the center is a labellum. The so-called "lip". It is noteworthy that only the orchid family has this part of the flower. The “lip” plays the role of a landing site for insects that pollinate the plant. The color and shape of Labellum can be very different. It directly depends on the type of orchid. Orchid flowers can have various shapes and sizes from 1 to 25 centimeters.
Peduncle structure
The peduncle of an orchid is an shoot on which flowers form. In turn, it grows out of the sinus between the trunk and leaves of the plant. Peduncle changes annually. At home, it grows in the autumn or spring. If the formation of the peduncle does not occur, this may mean that the plant does not have enough light. As a rule, the problem is eliminated by moving to a more illuminated place. When the flowers fall, the peduncle dries out. Experts recommend cleaning it, and then dry the slices.
Orchidaceae is not only one of the oldest plant families on the planet, but also one of the most beautiful. Such a culture is able to bring its own zest to any interior, and knowledge of the plant structure will ensure proper care for it.