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The embryonic plant stem above the cotyledons.



the part of the stem in a plant seedling between the cotyledons and the first true leaves (the first internode). In embryos the epicotyl is a conoid outgrowth consisting of primary formative tissue, or meristem. In plants with aboveground shoot formation the epicotyl and the cotyledons appear above the surface of the soil (for example, in beans and melons). In plants having underground shoot development the cotyledons remain in the soil, and the epicotyl is bent into a loop and then straightened; it carries the bud with the first leaves to the surface, toward the light (for example, in peas, plums, and oaks).

References in periodicals archive ?
In vitro organogenesis has been obtained in several citrus cultivars by the cultivation of epicotyl and internodal segments in BAP supplemented culture medium (Ghorbel et al., 1998; Moura et al., 2001; Almeida et al., 2002, 2006; Silva et al., 2005a, 2005b; Schinor et al., 2006) or with BAP and NAA supplementation (PErez-Molphe-Balch & Ochoa-Alejo, 1997, Bordon et al., 2000; Moreira-Dias et al., 2000, 2001; Schinor, 2006).
Caption: FIGURE 2: Effect of BA, with and without IBA or NAA, on the shoot regeneration rate in explants from epicotyls of Aspidospermapolyneuron.
Those obtained from the cytokinin treatments showed high survival rate (86.795.6%), thickening of hypocotyls, strong reduction of epicotyls and roots with few or no lateral root formation (Fig.
The epicotyl (Figure 4A) consists of uniseriate epidermis with unicellular non-glandular trichomes, collenchymatous and parenchymatous cortex, and central cylinder composed of two collateral vascular bundles and phloematic strands that surround the parenchymatous pith.
Thus, the minimum optimal number of plants to be measured to represent the average hypocotyl length was 45, 53, 52 and 45 for BRS Valiosa RR, Agua-Marinha RR, UFVS 2010 and NK 7059 RR, respectively, whereas the average length of the epicotyls was 49, 43, 51 and 49 for BRS Valiosa RR, Agua-Marinha RR, UFVS 2010 and NK 7059 RR, respectively (Figure 1).
curcas cultures: leaf, petiole, stem, cotyledons, epicotyls, hypocotyls, penduncle, nodal segments, apical shoots and axillary bud-derived shoots (Kaewpoo and Te-chato, 2009; Rajore et al., 2002; Sardana et al., 1998; Sujatha and Mukta, 1996; Sujatha and Reddy, 2000; Thepsamran et al., 2008; Wei et al., 2004).
The magnitude of such effects and also the most suitable pH for growth varied among organs, but, in each one of the latter, trends for L and FW were similar, excepting epicotyls and leaf blades (in which length was not measured).
Effect of ethylene treatment on polar IAA transport, net 1AA uptake and specific binding of N-l-naphthylphthalamic acid in tissues and microsomes isolated from etiolated pea epicotyls. Plant Physiol.
Purification and properties of amine oxidase from epicotyls of Pisum sativum.
Molecular cloning and characterization of a brassinosteroid-regulated gene from elongating soybean (Glycine max L.) epicotyls. Plant Physiology.
Ohashi] epicotyls as cell wall maturity and distance from the apex increased (Nishitani and Masuda, 1979).