A COMPARATIVE ANATOMICAL CHARACTERISTICS OF THE STEMS OF CLIMBING PLANTS IN ARALAM WILD LEFE SANCTUARY, KANNUR

Climbing plants differ from self-supporting plants, such as shrubs and trees, in a range of characteristics. The most notable is the mechanical properties of the stem Comparison of the differentiated anatomical structures recorded in ten species of the climbing plants. The plants selected for the present study are Ampelocissus latifolia,(Vitaceae), Lygodium flexuosum (Lygodiaceae), Centrosema virginianum(Fabaceae), Tinospora cordifolia,(Menispermaceae), Wattakakka volubilis (Asclepiadaceae) Cyclea peltata (Menispermaceae), Calycopteris floribunda (Combretaceae) Pothos scandens(Araceae) Ipomoea separia (Convolvulaceae) and Piper nigrum (Piperaceae). The stems of climbing plants are characterized by the scarcity of supporting cells (fibers) and an increase in the diameter of the xylem vessels. The study con firms that they show a greater diversity of organization than other plant life forms. This anatomical radiation couldprobably not exist without the achievement of a wide range of secondary growth processes. Many dicotyledons, notably those with a climbing habit, show interesting secondary structure which differs from the more usual type described, therefore, sometimes termed anomalous. The variant secondary growth isparticularly widespread in tropical climbers. It is speculated that variant growth can increase stem flexibility, protect the phloem, increase storage parenchyma, aid in clinging to supports, limit physical disruption of vascular tissues during twisting and bending, and promote wound healing after girdling.