bract


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Related to bract: epicalyx

bract

a specialized leaf, usually smaller than the foliage leaves, with a single flower or inflorescence growing in its axil

Bract

 

a leaf in whose axil the flower develops; a leaf enveloping a flower shoot. Bracts are smaller than ordinary leaves and are reduced. Only in a few plants, such as sage, are they large and colorful. Sometimes, for example, in Cruciferae and dill, the bracts fall early.

bract

[brakt]
(botany)
A modified leaf associated with plant reproductive structures.
References in periodicals archive ?
Poinsettia "flowers" are botanically bracts that surround the true flowers.
Species similar to Psittacanthus lasianthus, from which it differs by the sympodial, densely puberulous, three-angled stems, ternate leaves, terminal dichasia, perfoliate bracts, a neck-bearing, not inflated corolla densely laciniate on its outer surface and a triangular, ligule on the inside of each petal, a ring-like nectary, and a micropapillose stigma versus percurrent, glabrous, circular stems, paired leaves, axillary dichasia, not perfoliate bracts, a neck-lacking, inflated corolla without laciniae on its outer surface and a finger-like ligule on the inside of each petal, a 4-lobed nectary, and a smooth stigma in P.
However, there is limited information about the relationships between bract colour and pigment composition during the inflorescence development in this ornamental rhizomatic species.
Multicategoric characters were: (1) primary head shape: round, elliptical, oval, triangular and large transverse elliptical; (2) head tip shape: pointed, round, flat and depressed; (3) external bracts tip shape: pointed, flat and emarginated; (4) external color of the bracts: green, violet-striped green, green-striped violet, mainly violet and totally violet; and (5) anthocyanic pigmentation of the petiole: absent, mild, partial, strong and very strong.
Bracts are entire, 1-8 mm length, from sessile to amplexicaul.
bryoides based on material from "near Cordoba", "near Tucuman" ( = Lorentz 73), and "near Jujuy", but describing longer leaves (8,5-10 mm vs 6,3-8,5 mm), shorter bracts (4,2-5,3 mm vs.
The storage of inflorescences at temperatures of 12 and 19[degrees]C did not alter bract color.
They are characterized by a collar-like ring of large, sometimes brightly colored, bracts that enclose the inflorescence, making them look rather like an artichoke.
Floral defense by nocturnal bract closure represents an addition exaptation, because the defense function was added to the advertisement function without the latter being lost.
The morphological characters that contributed the most to genetic diversity in this study were bottom thickness, bottom fresh mass/head fresh mass ratio, bottom diameter, outer bract length, primary head length, bract base length, plant diameter, leaf length, primary head diameter, bract base thickness and plant height.