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

That the primary root of all educational activity is in the instinctive, impulsive attitudes and activities of the child, and not in the presentation and application of external material.

From The History of Education; educational practice and progress considered as a phase of the development and spread of western civilization by Cubberley, Ellwood Patterson

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 Gray, Asa

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 Gray, Asa

Inasmuch as the growth of the primary root is soon overtaken by other roots growing from the stem, all the roots happen to be of the same size.

From A Handbook of Some South Indian Grasses by Rangachari, K.

When the primary root grows more rapidly than the secondary roots, the so-called taproot, characteristic of lucerne, clover, and similar plants, is formed.

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