All angiosperms have flowers. These are modified shoots. And some plants form single flowers, and some - whole inflorescences.
What is an inflorescence?
This is not a separate modified shoot, but a whole system of them, from which fruits with seeds are then formed. Inflorescences are usually separated from the vegetative organs of the plant.
Classification of inflorescences
They can be classified according to the presence of leaves on them, depending on the degree of branching, according to the direction of opening of the flowers, according to the type of their growth and according to the type of apical meristems.
Types of inflorescences depending on the degree of branching
This is the most common classification. Inflorescence types classified using this method are considered in biology lessons at school.
According to this division, inflorescences can be, first of all, simple and complex.
Simple and complex inflorescences
Simple are those that have single flowers along the main axis.
Complex ones are those in which branching is three or more orders of magnitude.
For a detailed review of each group of inflorescences, see the table below:
| Simple | Type | Description |
| Brush | Flowers are distributed evenly along the entire axis. They are planted on pedicels. | |
| Spike | Flowers also grow more or less evenly along the entire length of the axis. However, such an inflorescence differs from the brush in that the flowers do not have pedicels. | |
| Shield | This is a kind of brush. In the corymb, the lower pedicels are longer, so that all the flowers line up in a horizontal row. | |
| Umbrella | This, like many other simple types of inflorescences, is a modified brush. Its axis is shortened, the pedicels are not located along its entire length, but all grow from the top. They are the same length, and the flowers line up in something like an umbrella dome. | |
| Head | The axis of such an inflorescence has a club-like shape. She is shortened. The flowers are arranged more or less evenly along its entire length. No pedicels. | |
| Basket | The end of the axis of such an inflorescence is strongly overgrown. It turns into a common bed for many tightly closed flowers. | |
| Cob | This is a modified ear with a very thickened axis. | |
| Complex | Panicle | Branched inflorescence. The degree of branching decreases towards the top of the axis. |
| Complex shield | A modified version of the previous type of inflorescence. The internodes of the main axle are shortened. | |
| Complex spike | Along the axis more or less evenly collectedsimple ears. | |
| Complex umbrella | It is formed from many simple umbrellas assembled on the main axis. |
So we looked at the main types of inflorescences. They all need to be known. Now let's talk about plants that have certain inflorescences.
Which plants have which inflorescences?
Let's look at the types of plants that have the inflorescences discussed above.
So, for example, a plant such as spring primrose has an umbrella type of inflorescence, while corn has an ear.
Let's take a look at the table in more detail.
| Types of inflorescences | Examples of plants |
| Brush | All cruciferous plants such as cabbage, turnip, watercress, shepherd's purse |
| Spike | Lyubka, plantain, verbena, sedge |
| Shield | Pear |
| Umbrella | Ginseng, spring primrose, garlic, onion |
| Head | Clover |
| Basket | Many Compositae like sunflower, aster, etc. |
| Cob | Corn |
| Panicle | Lilac, spirea |
| Complex shield | Millenium, mountain ash |
| Complex spike | Wheat, wheatgrass, barley |
| Complex umbrella | Parsley, carrot, dill |
Other classifications of inflorescences
Depending on the presence of bractsthree groups are distinguished on inflorescences:
- ebracteous;
- bracteose;
- frondose.
Inflorescences of the first group are devoid of bracts. This type includes cruciferous plants, as well as other plants, such as wild radish.
In bractose inflorescences, bracts have a scaly shape. Lilac, cherry, lily of the valley have such.
Frondous inflorescences have bracts with well-developed plates. Such plants as loosestrife, fuchsia, violets, etc. have these.
Depending on the type of growth and the direction of opening of flowers, the inflorescences can be divided into two groups:
- cymose;
- rational.
The first flowers open in the direction from the top of the axis to its base. The cymose group includes plants such as lungwort.
In the racimous type, the flowers open in the direction from the base of the axis to its top. These are plants such as, for example, shepherd's purse, as well as Ivan-tea and others.
And the last classification of inflorescences - depending on the type of apical meristems. These are educational tissues located at the top of the shoot. According to this classification, there are two groups of inflorescences:
- open;
- closed.
Open is also called indeterminate. In them, the apical meristems remain in a vegetative state. Hyacinths, lilies of the valley, etc. have such inflorescences.
Still closedare called defined. Apical flowers are formed in them from apical meristems. Such have, for example, lungwort, bell.
