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bean seed germinating


1. Botany A leaf of the embryo of a seed plant, which upon germination either remains in the seed or emerges, enlarges, and becomes green. Also called seed leaf.
2. Anatomy One of the lobules constituting the uterine side of the mammalian placenta, consisting mainly of a rounded mass of villi.

[Latin cotylēdōn, navelwort, from Greek kotulēdōn, from kotulē, hollow object.]

cot′y·le′don·ar′y (-ēd′n-ĕr′ē), cot′y·le′don·al (-ēd′n-əl), cot′y·le′do·nous (-ēd′n-əs) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
References in periodicals archive ?
Seeds/pellets presenting the cotyledonary leaves above the surface of the substrate were considered as emerged, with a final count at 50 days after the test installation (BRASIL, 2009).
On the other hand, shade reduced root growth at 21 DAE, although already at 12 DAE the curves presented a differentiated pattern of growth as a consequence of the reduction of cotyledonary reserves.
Source-sink regulation of cotyledonary reserve mobilization during cashew (Anacardium occidentale) seedling establishment under NaCl salinity.
A high-efficiency Agrobacterium tumefaciens mediated transformation system using cotyledonary node as explants in soybean (Glycine max L.).
Furthermore, exposure of micropropagated, cotyledonary nodal explants of mung beans to varying concentrations of benzylaminopurine, a cytokinin, resulted in decreased shoot proliferation at the highest concentration (5 ppm).
State and phase transition behaviors of Quercus rubra seed axes and cotyledonary tissues: relevance to the desiccation sensitivity and cryopreservation of recalcitrant seeds.
In Ocotea catharinensis improved total PA levels were observed in globular-staged somatic embryos, with decreased levels during cotyledonary stage (Santa-Catarina, Hanai, Dornellas, Viana, & Floh, 2004).
A = Output operculum; B, C = protrusion of the cotyledon petiole; D = Emergence of primary root; E = emission of the first cotyledonary sheath; F = emission of second of cotyledonary sheath and emission of secondary and tertiary roots; G and H = emission of first eophyll; op = operculum; pc = cotyledon petiole; bc = cotyledonary sheath; b1 = first sheath; b2 = second sheath; b3 = third cotyledonary sheath; rp = primary root; rs = secondary root;, rt = tertiary root; pe first = first eophyll (Pictures: JOAO BARROS SILVEIRA, 2010).
The results showed that various optimal parameters such as 100 mg L-1 of kanamycin concentration for selection of transformants, 2 d of pre-cultivation time, 100 umol L-1 of acetosyringone concentration, 15 min of infection time and 2 d of co-cultivation time were obtained using cotyledonary node explants.
(A) Embryogenesis (embryo indicated with arrow) (B) callusing (C) Cotyledonary embryo (D) Regenerated embryo (E) Regenerated plantlet (F) Adapted plants
Under laminar flow (Class II, Jal Tajhiz, Iran) in sterile condition, six full-thickness samples of endometrial tissue (10 x 10 x 5 [mm.sup.3]), four on both horns and two on the uterine body from both cotyledonary and intercotyledonary regions, were collected using sterile (autoclaved) surgical instruments (Figure 1).