Tropic Movements Types

Tropic movements, also known as Tropisms, is a unidirectional movement of plants. It happens in response to different environmental stimuli.

Plant Tropisms

There are six major types of tropic movements in plants as mentioned below:

Phototropism

The phototropism happens under the rection of light. In phototropism, plants grow towards light or grow away to the opposite direction of the light. In general, the plant stems are usually positive for phototropism. On the other hand, the plant roots show negative phototropism which grows against the light in the soil. The leaves also respond positively toward the light source.

• Phototropism is a tropic movement in plants. In simple words, it is the growth of a plant in response to an external stimulus.
• It involves plants orienting their growth towards or away from a sunlight source.
• The plant hormones, like auxins, help in the growth of the light source.
• Phototropism helps the leaves to grow in the sunlight. It helps to increase their ability to produce energy through photosynthesis.

Gravitropism

Gravitropism is a tropic movement in plants that responds to gravity by growing towards it. The shoots are gravitropism negative and roots are the gravitropism positive. Gravitropism is also known as the geotropism. The leaves are generally geotropic as they select their positions at right angles. Leaves stay intact with the steams at the center of gravity.

• Gravitropism is generally involved with the growth or movement of plant parts majorly roots and stems.
• This type of tropic movement helps the plants to orient themselves properly in the soil.
• This particular tropic movement optimizes the growth of roots and stems. It also ensures that roots penetrate the soil and shoots will grow towards sunlight.

Also Read: Difference between Shoot and Stem

Chemotropism

Chemotropism is a tropic movement in plants that is majorly caused by specific chemical compounds. This tropic movement results in the curvature movement in different plant organs.

• Chemotropism helps the plants locate the nutrients, water, or other necessary substances to grow and survive.
• During fertilization, this process is really helpful as it helps in the movement of pollen tubes towards ovules.

Also Read: Fertilization in Plants

Thigmotropism

Thigmotropism is a tropic movement in plants where the plants grow or develop in reaction to contact with a solid object. It is also known as haptotropism.

• Thigmotropism generally involves in the directional growth of the roots, stems, or tendrils.
• This tropic movement helps a plant to adapt new environment.
• In this movement, plats generally find support to grow by wrapping or climbing on them.

Thermotropism

Thermotropism is a type of tropic movement where a plant or a plant portion reacts to changes in the ambient temperature.

• Thermotropism is the tropic movement of plants in which they respond to the temperature and heat resources.
• This tropic movement generally depends on the species of a plant and on the conditions where the plant grows.
• Thermotropism helps plants to regulate the functions like photosynthesis, seed germination, and overall growth and development of a plant.

Hydrotropism

Hydrotropic is a tropic movement that helps a plant’s movement or growth in response to water stimulus or water sources. In this tropic movement, roots migrate and grow towards the water. Through this process, plants display a positive response to being hydrotropic.

• Hydrotropism allows the plants to locate and access water resources.
• The water resources generally lead this movement through specialized cells present in a root tip.
• Hydrotropism helps the plants to adapt the soil moisture levels to increase the resilience to the drought conditions.

Tropic Movements in Plants are also known as Plant Tropisms. It is a unidirectional movement of the plants that happens due to the response to different stimuli. This movement can occur in the same direction, or it is also possible to take place in the opposite direction of a particular stimulus. Plant movements take place when they need light, water, essential nutrients, etc. to live. In this article, we are going to discuss the Tropic Movements in Plants, types of tropic movements, processes, examples, and advantages.