Tropism is the bending of a plant as a result of certain factors

Today we will talk about some diseases of plants. They are an integral part of our lives. Try to imagine life without our green brothers. We would not have paper, furniture, this incredible natural beauty, and most importantly - oxygen. That is, without plants, we would not have been either. Today we will talk about a disease called "tropism". This is a bending occurring as a result of some factor (gravity, light, and so on). We will discuss this issue in more detail later.

To begin with, it is important to remember that tropism is not a norm, but a disease. It is necessary to help plants that suffer, of course, if there is such an opportunity.

We propose to proceed directly to the characterization of tropism and the analysis of its varieties. Let's start right now.

Tropism

So, tropism - is the bending of any part of the plant, from Greek this term is translated as "turn". This defect can be caused by a number of factors, which include:

• shine;
• Gravity and many others.

Tropism is a process that results in a faster growth of cells on one side of the shoot (leaf, stem or other parts of the plant). If we decided to characterize this disease, then the first thing that should be paid attention is the factor that caused it. For example, let's take phototropism, which is the most common in our life. It is expressed as turning a plant or some of its organs in one direction, this is caused by one-sided lighting. Two kinds of phototropism can be distinguished:

• Positive (if the plant turns to the light source);
• Negative (if the plant turns away from the light source).

As for phototropism, Charles Darwin began to study this phenomenon for the first time. He noted that the tip of the plant is capable of responding to light stimuli, which leads to bending. The response occurs in the stretching zone, that is, slightly below the area that reacts to light. This discovery allows us to assert that the receptors and cells that respond to stimuli are disconnected, which led to speculations about the existence of hormones that act and are synthesized in different places. Now we offer to consider some varieties of tropism, with one of them we got acquainted in this section.

Varieties of plant tropism

In this section, we will consider the tropism of plants of the most common species. We can distinguish such types as:

• phototropism;
• geotropism;
• Hemotropism;
• Hydrotropism;
• Tigmotropism;
• thermotropism;
• Electrotropism.

Now a few words about each kind. About the first we have already told a little. Phototropism is the bending of a plant as a result of one-way exposure to light. He can not show himself in any way, if after a long stay in the darkness to illuminate the plant with bright light.

Geotropism is the bending of the axial organs of a plant in connection with the action of gravity. If geotropism is positive, then the plant germinates incorrectly with respect to the earth. Hemiotropism is caused by the uneven distribution of chemicals in the soil. Hydrotropism is caused by an improper distribution of water. Tigmotropism is caused by physical effects (contact, pressure, and so on). Thermotropism occurs under the influence of unilateral heat, and electrotropism - an electric current.

We also denote that hydrotropism and tigmotropism are varieties of hemotropism.

Nastia

The Greek word "naso" means seal or closure. If tropism is associated with changes in the growth process, it is caused by various factors, then the nastiness is a change under the influence of stimuli that affect uniformly all organisms. These factors include:

• Changes in air temperature;
• Humidity;
• Natural lighting and so on.

A very good example is the behavior of tulip flowers: when the sun sets - they close, when it rises - they open. This phenomenon is called niktinastyami, or sleepy movements.

Taxis

Now a few words about taxis, which are also caused by external factors. It is the movement of the whole living organism. We said that tropisms are divided into positive and negative. We can also assign the same classification to taxis. In addition, they can be classified according to stimuli:

• Tigmotaxis;
• Phototaxis;
• Chemotaxis.

We considered such a disease of plants as tropism. We hope that the information was useful!