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

See Examples For:

hyponasty

As the rectangularly bent portion of an upright stem grows older, the lower part straightens itself; and this is effected through hyponasty.

From The Power of Movement in Plants by Darwin, Charles

There can therefore be no doubt that the straightening of the abruptly curved portion of the growing stem of this plant, which appears to be wholly due to hyponasty, is the result of modified circumnutation.

From The Power of Movement in Plants by Darwin, Charles

When the pod is nearly ripe, the upper part straightens itself and becomes erect; and this is due to hyponasty or apogeotropism, or both combined, and not to heliotropism, for it occurred in darkness.

From The Power of Movement in Plants by Darwin, Charles

As the arching occurred in whatever position the seeds were placed, it is no doubt due to temporarily increased growth of the nature of epinasty or hyponasty along one side of the part.

From The Power of Movement in Plants by Darwin, Charles

The hooking depends chiefly, as far as we could ascertain, on the tip being affected by epinasty and geotropism; the lower and older parts continually straightening themselves through hyponasty and apogeotropism.

From The Power of Movement in Plants by Darwin, Charles