Storage Organ - Other Storage Organs

Other Storage Organs

Succulents are plants which are adapted to withstand periods of drought by their ability to store moisture in specialized storage organs.

• Leaf succulents store water in their leaves, which are thus thickened, fleshy and typically covered with a waxy coating or fine hairs to reduce evaporation. They may also contain mucilagenous compounds. Some leaf succulents have leaves which are distributed along the stem in a similar fashion to non-succulent species (e.g. Crassula, Kalanchoe); their stems may also be succulent. In others, the leaves are more compact, forming a rosette (e.g. Echeveria, Aloe). Pebble-plants or living stones (e.g. Lithops, Conophytum) have reduced their leaves to just two, forming a fleshy body, only the top of which may be visible above ground.

• Stem succulents are generally either leafless or have leaves which can be quickly shed in the event of drought. Photosynthesis is then taken over by the stems. As with leaf succulents, stems may be covered with a waxy coating or fine hairs to reduce evaporation. The ribbed bodies of cacti may be an adaption to allow shrinkage and expansion with the amount of water stored. Plants of the same general form as cacti are found in other families (e.g. Euphorbia canariensis (family Euphorbiaceae), Stapelia (family Apocynaceae)).