Rachis

(1) Rachis (of compound leaf)

Dictionary of botanic terminology - index of names

The main stalk (axis) of a pinnate leaf above and continuous to the petiole

The rachis extends from the first set of leaflets (where the petiole ends) to the end of the leaf; as well the stalk of a pinna in a bipinnate compound leaf and that part of a fern frond stalk that bears the leaflets

(2) Rachis (of inflorescence)


	*The main stalk (axis) of an inflorescence, above the peduncle, bearing flowers. e.g. of a floral spike or a raceme*

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Holdfast roots [ Botany ]
Dictionary of botanic terminology - index of names

Some species of climbing plants develop holdfast roots which help to support the vines on trees, walls, and rocks. By forcing their way into minute pores and crevices, they hold the plant firmly in place.

Climbing plants, like the poison ivy (Toxicodendron radicans), Boston ivy (Parthenocissus tricuspidata), and trumpet creeper (Campsis radicans), develop holdfast roots which help to support the vines on trees, walls, and rocks. By forcing their way into minute pores and crevices, they hold the plant firmly in place. Usually the Holdfast roots die at the end of the first season, but in some species they are perennial. In the tropics some of the large climbing plants have hold-fast roots by which they attach themselves, and long, cord-like roots that extend downward through the air and may lengthen and branch for several years until they strike the soil and become absorbent roots.

Major references and further lectures:
1) E. N. Transeau “General Botany” Discovery Publishing House, 1994