Ans.Vegetative Propagation
When vegetative parts of plants i.e. roots, stems or leaves give rise to new plants, the process is called vegetative reproduction or vegetative propagation. It occurs naturally, and can also be brought about artificially. Figure 14.8
Natural Vegetative Propagation
Vegetative propagation occurs naturally in several ways.
1.Bulbs are short underground stems surrounded by thick, fleshy leaves that contain stored food. Adventitious roots .emerge under the base of bulb while shoots emerge from the top of the base. Examples: Tulips, onions and lilies reproduce by bulbs.
2. Corms are short and swollen underground stems containing stored food. Buds are present at the top of corm. From a bud, shoot grows and forms a new plant.
Examples: Dasheen and garlic reproduce by corms.
3.Rhizomes are horizontal underground stems with scale leaves. There are enlarged portions called nodes on rhizome. Buds are produced at nodes. The buds present on the upper surface of rhizome give rise to shoot. The lower surface of rhizome produces adventitious roots.
Examples: Ginger, ferns and water lilies reproduce by rhizomes.
1. Stem Tubers are the enlarged portions of an underground stem (rhizome). There are aggregations of tiny buds in the form of "eyes" along the surface of tuber..Each bud develops onto shoot that grows upward'and also produces roots.
Examples: Potatoes and yams reproduce by tubers
2.Suckers are lateral stems close to ground level. A sucker grows underground for some distance and then turns up, producing the new plant.
Examples:Mint and Chrysanthemum reproduce in this way.
3.Vegetative propagation by leaves is not common and is seen in plants such as bryophyllum (Pather chut). This plant has fleshy leaves and adventitious buds are present at the margins of leaves. When falls. on ground, the buds grow into new
plants. Figure 14.9