primary root

American  

noun

Botany.

1. the first root produced by a germinating seed, developing from the radicle of the embryo.

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primary root Scientific  

1. The first root of a plant, originating in the embryo. In gymnosperms, eudicotyledons, and magnoliids, the primary root develops into the taproot. In monocotyledons, the primary root disintegrates as the lateral roots develop into a system of fibrous roots.

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Etymology

Origin of primary root

First recorded in 1885–90

Example Sentences

See Examples For:

primary root

Grain of Indian Corn in germination, the ascending sprout is the first leaf of the plumule, enclosing the younger leaves within, at its base the primary root has broken through.

From The Elements of Botany For Beginners and For Schools by Asa Gray

The single root of the commoner biennials is the primary root, or tap-root, which begins to thicken in the seedling.

From The Elements of Botany For Beginners and For Schools by Asa Gray

These are exactly like the primary root from which they spring; there is no difference in structure or in machinery of growth. 

From Rustic Sounds and Other Studies in Literature and Natural History by Sir Francis Darwin

The growth of the primary root is limited; sooner or later adventitious roots develop from the axis above the radicle which they ultimately exceed in growth.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 3 "Gordon, Lord George" to "Grasses" by Various

From this primary root other roots develop, which are known as secondary roots.

From Dry-Farming : a System of Agriculture for Countries under a Low Rainfall by John Andreas Widtsoe