orthotropism

biology

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July 1, 2026

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Orthotropism is a biological term describing the tendency of a plant to grow with its main axis oriented vertically. This is a specific type of tropism, which is a plant's directional response to a stimulus. Most tropic movements are orthotropic, meaning they are directed toward the source of the stimulus, such as light or gravity. In contrast, plagiotropism refers to growth that is oblique to the direction of the stimulus. Orthotropism ensures that plants grow upright, which is crucial for their development and interaction with environmental factors like sunlight and gravity.123

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tropism
Most tropic movements are orthotropic; i.e., they are directed toward the source of the stimulus. Plagiotropic movements are oblique to the direction of stimulus. Diatropic movements are at right angles to the direction of stimulus.
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Most tropic movements are orthotropic; i.e., they are directed toward the source of the stimulus. Plagiotropic movements are oblique to the direction of stimulus. Diatropic movements are at right angles to the direction of stimulus.
Read More