Thursday, 7 April 2011

What is Vegetative Reproduction

Vegetative reproduction is applicable for plants only, and is categorized under asexual reproduction. The alternative names for this type of reproduction are vegetative cloning, vegetative multiplication and vegetative propagation. Cloning is so called, as the resulting offspring are genetically similar to the parent plant.Vegetative propagation can be conducted manually by artificial methods. More info on what is vegetative reproduction and its various examples are highlighted in the upcoming paragraphs.

What is Vegetative Reproduction in Plants?

Vegetative reproduction is defined as the production of new plantlets from the vegetative parts (leaf, stem, roots) of the parent plant. For this to take place, there is no need for pollination, fertilization of the male and female reproductive cells, production of spores and any such processes that require male and female gametes. Since no meiosis or syngamy takes place, the daughter plants are similar to each other, and also to the mother plant. Some profound examples of natural vegetative reproduction in plants are listed below:

  • Buds formation in the edges of a kalanchoe leaf, which later grows as individual plants.
  • Production of daughter strawberry plants from runners. The same is observed in spider and ivy plants.
  • Corm formation of gladiolus, iris, saffron, arrowhead, etc. as a means to produce new plants.
  • The fleshy stem of ginger and turmeric grows underground, and produces several plants from it.
  • Plants of the lily family (onion, garlic, tuberose, etc.) produce bulbs for vegetative reproduction.
  • Development of gemmae in mosses and liverworts, which after detaching from the mother plants give rise to new plants.
  • Potato and dahlia tubers containing eyes are buried in the soil for developing new plants.
The types of vegetative propagation that are commonly studied in horticulture science are budding, grafting, layering, marcotting and cuttings. Another complex kind of vegetative cloning that is carried out under controlled laboratory conditions is called plant tissue culture. This involves culturing of a specific plant part in a nutrient medium and providing required growth factors. With the advent of this technique, cultivation of plants that do not produce seeds or those that give nonviable seeds has become very easy.

An Overview of Vegetative Reproduction

There are both advantages and disadvantages of vegetative propagation. A concern with natural vegetative propagation is, the new plants detached from the parent grow in the same area, resulting in crowdedness. This leads to competition amongst the plants in the specific growing area for space, light and nutrition. As expected, they have less vigor, and many die due to lack of sufficient light and food. The major advantages of this asexual reproduction in plants are mentioned below:
  • With this asexual reproduction type, parent plants can give rise to new offspring on their own. They do not need pollinating agents (like, wind, water and insects) for promoting fertilization.
  • Only one plant is sufficient for giving rise to offspring without undergoing the hassles of cross pollination, which is crucial for some plants (e.g. apple). Thus, from a single plant, you can propagate many plantlets by vegetative cloning.
  • Desirable attributes of the parent plant are restored in the offspring without alteration, which is not so with seed propagated plants. Thus, juicy and sweet apple varieties are commercially produced by grafting method.
  • Offspring are produced at a faster rate from the vegetative parts that store essential nutrients. Also, the new plants after separating from the mother plant establish to the particular area more easily.
This was a brief explanation on 'what is vegetative reproduction' along with examples and advantages. The con side of this propagation method lies in the fact that, the resulting daughter plants are clones of the parent plant and you cannot expect any variation in them. While this is beneficial for restoring qualitative traits in the offspring, it reduces adaptation and survival rate of new plants to the prevailing climate. In other words, variation in plants propagated by means of seeds is beneficial to cope up with the ever changing environmental conditions.

No comments:

Post a Comment