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The downward bending of a leaf or other plant part, resulting from greater growth of the upper side than of the lower side.

ep′i·nas′tic (-tĭk) adj.


n, pl -ties
(Botany) increased growth of the upper surface of a plant part, such as a leaf, resulting in a downward bending of the part. Compare hyponasty
[C19: from epi- + -nasty, from Greek nastos pressed down, from nassein to press]
ˌepiˈnastic adj


(ˈɛp əˌnæs ti)

increased growth on the upper surface of a plant organ or part, esp. a leaf, causing it to bend downward.
ep`i•nas′tic, adj.
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References in periodicals archive ?
Gross Lisse leaf curl Nicotiana benthamiana mosaic, rugosity, epinasty Nicotiana clevelandii no infection/ mild chlorosis Nicotiana edwardsonii no infection Nicotiana glutinosa no infection Nicotiana megalosiphon mosaic, necrotic fleck Nicotiana rustica no infection Nicotiana tabacum no infection cv.
The toxicity of 2,4-D was evidenced by the epinasty of the leaves, bending of the leaf over the bottom side and the stems bent toward the soil.
Symptomology can vary from chlorosis of the terminal buds, cupping or crinkling of canopy leaves, and leaf or stem epinasty. Higher rates can even result in stem cracking, terminal death, or plant death [17,21,22].
This was due to epinasty, which happens when the roots gets flooded.
Directional blue light irradiation triggers epidermal cell elongation of abaxial side resulting in inhibition of leaf epinasty in geranium under red light condition.
Moreover, the herbicidal effect of 2,4-D, even when applied only to the base of the cuttings, could harm the vital functions of the cuttings, because auxins can induce prejudicial metabolic and biochemical changes, such as in nucleic acids, the plasticity of the cell wall, and the action of the RNA-polymerase enzyme, and, consequently, in the synthesis of nucleic acids and proteins, and can also induce high cell proliferation in tissues, causing stem epinasty and phloem interruption (OLIVEIRA JUNIOR et al., 2011).
In tomato, epinasty which is induced by ethylene is a good indicator of salt-sensitivity [35], and ethylene biosynthesis is increased by salt stress [7].
Many authors have reported different protocols for in vitro culture of potato using different explants and different cultivars (Roest and Bokelman, 1976; Martel and de Garcia, 1992; de Garcia and Martinez, 1995; Seabrook and Douglass, 2001; Vargas et al., 2005); however, ethylene produced by tissue, callus and plantlets in closed vessels may lead to abnormal plantlet growth, hyperhydricity, abnormal branching in vitro, epinasty, leaf and flower bud abscission, diminution of foliar area (Turhan, 2004; Mullins et al., 2006; Zobayed et al., 2001; Zobayed, 2005; Hazarika, 2006; Steinitz et al., 2010; Giridhar, 2004; Dang and Wei, 2009; Jackson et al., 1991).