Hypocotyl


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hypocotyl

[′hī·pə‚käd·əl]
(botany)
The portion of the embryonic plant axis below the cotyledon.

Hypocotyl

 

in sprouting plants, the section of the stem extending from the root collar (the zone between the main stem and the root) to the place of attachment of the cotyledons. In the embryo, the hopocotyl is the rudimentary stem. The sprouts of some plants have an elongate hypocotyl that bears assimilative cotyledons. This type of aboveground germination characterizes hornbeam. In other plants the hypocotyl is underdeveloped, and the cotyledons do not appear on the surface. Such underground germination is typical of the pea and the oak.

The anatomical structure of the hypocotyl retains its embryonic character. It may give rise to adventitious shoots, roots, or leaves (when the apex of the epicotyl is removed, as in cyclamen). In some plants the hypocotyl becomes the repository of nutrients (for example, the tuber in cyclamen). In many root crops, including the turnip, carrot, and sugar beet, the hypocotyl consists of the fleshy part of the storage organ, which is found between the stem base and the root proper.

L. V. KUDRIASHOV

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The change of ambient magnetic field has remarkable effect on the inhibition of hypocotyl growth in plants and the circadian rhythms in mammals and insects.
In contrast, hypocotyl and root length (Figure 3 and 4) were affected by residual synthetic auxin in all three species investigated.
5) Dry weight of the radicle, cotyledon and hypocotyl,
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This exercise is introduced with a description of seedling morphology, including root hairs, cotyledons, hypocotyl, epicotyl and plumule.
As PODs, especially the anionic, are most likely involved in lignification, the enhanced lignin synthesis in the hypocotyl region and subsequent inhibition of hypocotyl growth by light is attributed to the increased activity of the anionic PODs.
The phenotypic evaluation of this allelic series will measure hypocotyl response under different light conditions.
The 113 species are described in both languages, providing scientific name, vernacular name(s) used in East Kalimantan, development of the seedling, including the hypocotyl, cotyledon(s) and epicotyl, leaves, habitat and ecology, uses, and notes, including information on the adult specimens and literature references.
for human dietary supplements comprising soy material made from ground soy hypocotyl containing at least one isoflavone.