Seeds and Seedling Vocabulary

Fruit: the mature ovary wall, generally containing seeds
Funiculus: stalk by which seed is attached to placenta in fruit

Seed Surfaces
Alate: winged
Circumalate: winged circumferentially
Comose: with a tuft of trichomes
Coronate: with a crown
Crested: with an elevated ridge or ridges; with raphe
Umbonate: with distinct projection usually from the side
Verrucose: warty

Seed Parts
Aril: fleshy outgrowth of funiculus, raphe, or integuments (seed coat)
Embryo: young sporophyte consisting of epicotyl, hypocotyl, radicle, and one or more cotyledons
Endosperm: food reserve formed from syngamy of central cell and sperm
Hilum: funicular scar on seed coat
Micropyle: hole through seed coat for delivery of sperm cells
Raphe: ridge on seed coat fromed from fused funiculus
Seed Coat: hardened integuments of ovule, protective covering of seed

Embryo Parts
Coleoptile: protective first leaf sheath surrounding epicotyl in grasses
Coleorhiza: protective sheath around radicle in grasses
Cotyledon: embryonic or seed leaf
Epicotyl: apical end of embryo axis above cotyledon
Hypocotyl: embryonic stem below cotyledons
Mesocotyl: embryonic stem axis between scutellum and coleoptile in grasses
Plumule: leaves of epicotyl in seed
Radicle: basal end of embryo axis, becoming root
Scutellum: the cotyledon in grasses

Seed Types
Cotylespermous: food reserve in cotyledon
Endospermous: food reserve in endosperm
Hypocotylespermous: food reserve in hypocotyl

Cotyledon Number
Monocotyledonous: one cotyledon
Dicotyledonous: two cotyledons

Cotyledon Size
Anisocotylous: unequal cotyledons
Isocotylous: cotyledons equal in shape and size

Radicle Position
Antitropous: radicle pointing away from hilum
Syntropous: radicle pointing toward hilum

Embryo Types
Bent: embryo with cotyledons folded back along the hypocotyl/radicle.
Broad: basal globular or lenticular embryo surrounded in endosperm
Capitate: basal head-like embryo surrounded in endosperm
Dwarf: embryo small compared to seed; seed in 0.2 to 2 mm long
Folded: embryo with thin extensive cotyledons folded and pleated in various ways
Investing: embryo with thick cotyledons as major portion with limited endosperm
Linear: axial embryo several times longer than broad, with thin cotyledons
Micro: axial embryo in minute seeds less than 0.2 mm long, occupying most of seed
Peripheral: embryo pressed along side of seed coat, remainder is endosperm
Rudimentary: undifferentiated embryo in copious endosperm

Cotyledon Position
Accumbent: with cotyledon edges against hypocotyl
Incumbent: with cotyledon sides against hypocotyl

Seedling Types
cotyledons remaining in seed and usually below ground
cotyledons emergent from seed and usually appearing above ground

Seedling Parts
Adventitious root: a root arising from stem, petiole, or leaf tissues
Cataphyll: rudimentary scale leaf in cryptocotylar species
Collet: external demarcation between hypocotyl and root
Eophyll: the first few green leaves developed by seedlings in transition to adult leaves
Lateral root: a branch root, a secondary root, arising from root tissue
Leaf primordia: young leaves having unexpanded blades
Metaphyll: adult leaves
Primary root: derived from radicle
Root apex: root meristem including terminal root cap
Root hair: epidermal cells of a young root extending outward among soil particles
Shoot apex: shoot meristem with leaf primordia

This page © Ross E. Koning 1994.

The CBE citation style for this page would be: Koning, Ross E. 1994. "Seeds and Seedling Vocabulary". Plant Physiology Website. (your visit date)

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