Scutellum


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Related to Scutellum: coleoptile

scutellum

[skü′tel·əm]
(botany)
A rounded apothecium with an elevated rim found in certain lichens.
The flattened cotyledon of a monocotyledonous plant embryo, such as a grass.
(invertebrate zoology)
The third of four pieces forming the upper part of the thoracic segment in certain insects.
(vertebrate zoology)
One of the scales on the tarsi and toes of birds.

Scutellum

 

one of the principal organs in the embryo of grasses of the family Gramineae. During seed sprouting, the scutellum secretes enzymes that make soluble the reserve substances of the endosperm that nourish the developing embryo. Some botanists regard the scutellum as a cotyledon, and others as a modified axis of the embryo.

References in periodicals archive ?
[With yellow on clypeus, propodeum, and posterior bands on T1-T2; usually with yellow also on scutellum and metanotum.
In many species, strong asymmetrical growth in the lower scutellum and coleoptile region of the proembryo displaces the root cap and plumule away from their original basal and lateral position (Goetghebeur 1986).
The eyes are completely hairy in subgenus Pandasyopthalmus and with double band of hairs, hind margin of scutellum with distinct teeth in subgenus Serratoparagus and without teeth in subgenus Paragus.
Pronotum bell-shaped, without middle carina and middle stria, without erect groups of scales; 1.5 times longer than width at apex, 0.7 times longer than width in middle and at base, widest near middle, narrowing to apex; lateral margins almost straight; anterior margin 0.5 times as long as posterior margin; pronotal punctures round, dense and large; distance between adjacent punctures distinctly smaller than diameter of puncture; intervals convex; scutellum rhombic, 1.5 times longer than width in middle.
Scutellum dark red-brown, silver pruinose except for tiny lateral areas, fine dark red-brown setose (2 long apical macrosetae moderately differentiated).
Scutellum: Basal third nearly impunctate, becoming more yellowish brown and densely punctate on distal two thirds.
Regeneration: Scutellum derived calli were shifted to a modified Murashige and Skoog"s (1962) medium supplemented with 3% sugar (sucrose, maltose or glucose) myo-inositol 100 mg/L, glycine 2 mg/L, nicotinic acid 0.5 mg/L, pyridoxin 0.5 mg/L, thymine 0.1 mg/L and solidified with gelling agent (phytagel, gelrite or agar).
Female: Overall length 2.90, length from tip of tylus to cuneal fracture 1.95, maximum width (across base of cuneus) 1.10; similar to male in general structure and coloration, with following exceptions: pronotum, scutellum, clavus and inner corium dark yellow, outer corium broadly pale green (Fig.
Isotopic changes approaching the [[delta].sup.13]C of the provided benthic diatoms were detected from postlarvae fed the benthic diatoms Achnanthes longipes, Cocconeis scutellum, C.
The nutlets form in a fruiting calyx called a scutellum that expands in size and changes in color from green to yellow and finally brown.
Immature embryos were dissected from young caryopses under a stereo binocular and the embryonic axis was bisected longitudinally to destroy the embryonic axis, then after 3 days remaining embryonic tissue at the half scutellum tissue was removed.
The students learn that the endosperm holds most of the corn starch, but the corn oil is mostly in the embryo, especially including the cotyledon (scutellum).