![]() (b) Physiological function – Conduction of mineral salts and water absorbed by roots and translocation of prepared food matters to various plant parts. (a) Mechanical function is the bearing of the crown and weight of entire plant, the production and bearing of foliage leaves, branches and reproductive structures like flowers and fruits. Ampelopsis veitchii – an adhesive climber Functions of Stem in Plant : In this plant the adhesive discs are developed from the tendrils. These climbers are provided with adhesive discs to some of their organs, by means of such adhesive discs they may adhere to flat surfaces, e.g. There is another type of climber called adhesive climber. This helps the plant to climb neighbouring plants or objects.Ĩ. ![]() In Calamus rotang, long slender whip-like stalk covered by prickles (hook-like) is produced from the leaf sheath. Bougainvillea spectabilis (Nyctaginaceae), climbing rose, Calamus rotang (Palmae) etc. Rambler or Scramblers:- Several plants have been found to climb neighbouring plants in forests with the help of prickles and thorns e.g. (Nepenthaceae) the modified petiole often twists round the support like tendril holding the pitcher in vertical position.ħ. (Ranunculaceae) is sensitive to contact and coil round any neighbouring object helping the plant to climb. Leaf Climbers:- Leaf climbers are the climbing plants in which the leaf or part of the leaf is modified into tendril and which act as climbing organ (see iv & v under tendril climbers). D - Prickles on the stem of Lantana sp.Ħ. C – A twig of Artabotrys uncinatus showing hook on flower stalk. A – Prickle of a portion of a climbing rose (Rosa sp.) B – Prickle of cane (Calamus rotang). Bignonia unguis-cati (Bignoniaceae) sometimes hooks are modified inflorescence axes, e.g. Hook-like structures are also formed due to the modification of terminal leaflets which also serve the climbing purpose e.g. Hook climbers :- In Artabotrys uncinatus (Anonaceae) curved hooks are developed from the flower stalks (pedicels) which help the plant to climb up any other plant or support. climb up suitable objects with the help of adventitious roots which develop from the nodes of the stem.ĥ. Root climbers: – Several weak plants like Pothos scandens (Araceae), Piper betle (Piperaceae), Scindapsus officinalis (Araceae), Ficus pumila (Moraceae) etc. Antigonon leptopus (Polygonaceae), Cardiospermum helicacabum (Sapindaceae) etc.Ĥ. (vi) Inflorescence axis is modified into tendrils e.g. (v) Stipules are modified into tendrils e.g. (iv) Apex of the leaf is modified into tendril e.g. Pisum sativum (Leguminosae-Papilionaceae). (iii) Terminal leaflets are modified into tendrils e.g. Lathyrus aphaca (Leguminosae-Papilionaceae). (ii) Entire leaf is modified into tendril e.g. (Vitaceae) the apical bud is modified into tendril. (i) Tendrils may develop from the axil of leaf and are called stem tendrils either the axillary bud is modified into slender coily structure e.g. C - Leaf apex tendril of Gloriosa superba. Different plant organs are modified to form tendrils. They help the plant to climb up any other plant or object. These are slender, spirally coiled, thread-like structures which may be modifications of either branches or leaves or inflorescence stalk and are very sensitive to contact. Tendril climbers - There are some plants which develop special type of climbing organs called tendrils. Tridax procumbens (Compositae), Lindenbergia indica (Scrophulariaceae) etc.ģ. (ii) Decumbent - When the stem lies over the ground with the apex turned upwards e.g. Basella rubra (Chenopodiaceae), Evolvulus nummularius, Ipomoea reptans (Convolvulaceae) etc. (i) Procumbent or Prostrate - When the stem lies prostrate over the ground, its apex also lies flat over the surface e.g. Types of weak plant stem:- Weak stems are either (a) Trailer - trails over the surface of the ground without rooting at the nodes, or (b) Creeper - grows horizontally over the surface of the soil striking roots (arising from the nodes) at short distance or (c) Climber - climbs up by supporting any other plant or object. WEAK STEMS:- Many stems are weak, they cannot maintain an upright position. Polyanthes tuberosa (Amaryllidaceae), Allium cepa (Liliaceae), aroids, etc.ī. The plant is defined as acaulescent, e.g. It comes out through the cluster of leaves and bears at its apex either a solitary flower or a cluster of flowers. Scape:- In some monocotyledonous plants the suppressed underground stem produces an erect unbranched aerial shoot which is known as scape. grasses such as Bambusa arundinacea (Gramineae). In this case the nodes are solid and the internodes are hollow, e.g. (d) Culm:- Jointed stems are known as culm. ![]()
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