Natural Methods of Vegetative Propagation in Plants - Practice Questions & MCQ

• In vegetative propagation, any part of the plant, i.e., stem, root, leaf or even buds are capable of giving rise to new plants.
• Methods of Vegetative Reproduction:
  • Natural methods and
  • Artificial methods.

Natural Methods:

• In such methods of vegetative propagation, a portion of the plant gets detached from the mother plant and develops into a new independent plant under suitable environmental conditions. 
• The detached parts may be roots, stems, leaves or flowers.

Natural Method of Vegetative Propagation by Roots:

• The ordinary roots in many plants, such as Dalbergia sissoo, Populus, Guava, Murraya, Albizia develop adventitious buds that grow to form new plants. 
• Root tubers with adventitious buds occur in sweet potato, Tapioca, Yam, Dahlia, and Asparagus.

Natural Method of Vegetative Propagation by Stem:

• Different plant parts, such as bulbs, runners, rhizomes, corms, tubers, offset, etc. help the plant to multiply under favorable conditions.
• The bulb is a modified shoot that has a very short stem and apical and axillary buds. Some of these grow to form shoots, e.g., Allium cepa (onion), Allium sativum (garlic)
• The runners are creeping stems that produce roots at nodes. Runners break at places and each piece develops into an independent plant, e.g., Cynodon (doob grass), Oxalis, etc. 
• The rhizomes are underground, horizontally growing stems. They have prominent nodes, internodes, and axillary buds. Aerial branches sprout from the axillary buds which get separated from the rhizome and form new plants, e.g. ginger.
• The corm is a condensed rhizome that grows in a vertical direction. The axillary buds, present in the axil of scale leaves, produce daughter corms which later on form new independent plants, e.g., Crocus (Saffron).
• The tuber is a modification of the underground stem. The “eyes” or buds present on the tuber form new independent plants. Potato (Solanum tuberosum) is the most common example.

Natural Method of Vegetative Propagation by Leaves:

• Leaves of a number of plants possess adventitious buds for vegetative propagation, e.g., leaf tips of walking fern (Adiantum caudatum), marginal notches in Kalanchoe and Bryophyllum. 
• In Bryophyllum, the marginal buds sprout while the leaf is attached to the plant. 
• In some other plants, the buds develop only when the leaf is injured or detached and fall on the moist soil, e.g., Begonia, Saintpaulia, and Streptocarpus.

Natural Method of Vegetative Propagation by Bulbils:

• Bulbils are fleshy buds that develop into new plants after falling on the soil, e.g. Agave, Oxalis, Pineapple, Dioscorea, Lily, Chlorophytum, etc. 
• Some of them are modified floral buds, e.g., Agave. 
• In Dioscorea, they develop in the axils of leaves while in Oxalis they occur above the base of the fleshy root.