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The first leaf of a monocotyledon seedling.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



the first leaf of cereal grasses, which has no blade and consists of a closed tubule. It is colorless, green, or reddish. The coleoptile encloses and protects the young sprout, the plumule, and the growing point of the stem. It penetrates the soil with its hard apex, which then ruptures; causing the grain to sprout. A new leaf emerges from the top of the coleoptile. The coleoptile, which subsequently dries up, apparently is the middle part of the cotyledon.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Goetghebeur (1986) proposed the Cyperus-type as a specialised Helothrix-type, with a lateral displacement of the root cap caused by the strong outgrowth of the coleoptile, which results in a basal position of the first primordial leaf (Fig.
Summary of the analysis of variance for the first count (FC), germination (G), electrical conductivity(EC), coleoptile length (CL) and radicle length (RL).
salicifolius on the elongation of wheat coleoptile and the high phytotoxicity of ethyl acetate extract on the germination, growth and metaxylem cell elongation in sesame seedlings.
Coleoptile growth was stimulated by diffractaic (1) and hypostictic (2) acids, but inhibited by protocetraric (3), salazinic (4), secalonic (5), and usnic (6) acids and atranorin (7).
(1996) also observed increased coleoptiles speed of growth in wheat seedlings when they used A.
Three-dimensional progression of programmed death in the rice coleoptile. International Review of Cytology, v.58, p.218-221, 2002.
198), and that the "coleoptile is regarded either as the second leaf or as part of the cotyledon itself." Of course we cannot assign to the author of this one book any culpability for confusion in the botanical literature.
Darwin's experiments with the oat coleoptile showed that cells on the dark side of the stem elongate more rapidly than those on the light side.