hyponasty

American  

[hahy-puh-nas-tee] / ˈhaɪ pəˌnæs ti /

noun

Botany.

1. increased growth along the lower surface of a plant or plant part, causing it to bend upward.

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hyponasty British  

/ ˈhaɪpəˌnæstɪ /

noun

1. increased growth of the lower surface of a plant part, resulting in an upward bending of the part Compare epinasty

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Other Word Forms

• hyponastic adjective
• hyponastically adverb

Etymology

Origin of hyponasty

1870–75; hypo- + Greek nast ( ós ) pressed close, compact + -y ³

Example Sentences

Nature of the circumnutating movement—History of a germinating seed—The radicle first protrudes and circumnutates—Its tip highly sensitive— Emergence of the hypocotyl or of the epicotyl from the ground under the form of an arch - Its circumnutation and that of the cotyledons—The seedling throws up a leaf-bearing stem—The circumnutation of all the parts or organs—Modified circumnutation—Epinasty and hyponasty—Movements of climbing plants—Nyctitropic movements—Movements excited by light and gravitation—Localised sensitiveness—Resemblance between the movements of plants and animals—The tip of the radicle acts like a brain.

From Project Gutenberg

These changes of position, which are due to epinasty or hyponasty, occur at certain periods of the life of the plant, and are independent of any external agency.

From Project Gutenberg

The movements thus induced result from a modified form of circumnutation; for, as we shall immediately see, an organ under the influence of epinasty does not generally move in a straight line downwards, or under that of hyponasty upwards, but oscillates up and down with some lateral movement: it moves, however, in a preponderant manner in one direction.

From Project Gutenberg

At the same time there may be in addition, as De Vries insists, increased growth on one side due to geotropism, and on another side due to heliotropism; and thus the effects of epinasty or of hyponasty may be either increased or lessened.

From Project Gutenberg

He who likes, may speak of ordinary circumnutation as being combined with epinasty, hyponasty, the effects of gravitation, light, etc.; but it seems to us, from reasons hereafter to be given, to be more correct to say that circumnutation is modified by these several agencies.

From Project Gutenberg