Chapter 10, Problem 30A

Summary Introduction

To discuss:

The benefits and drawbacks of using cuttings to reproduce a certain type of plant

Introduction:

The main advantage of sexual reproduction is that it produces genetic variation in species. Genetic variation arises due to differences in genetic sequence in DNA among individuals. Genetic variation helps species survive better in adverse conditions. Vegetative propagation allows development of genetically identical plants.

Answer to Problem 30A

Benefits of reproducing through plant cuttings

• It allows production of genetically identical plants very quickly.
• Only one parent is involved so there is no need to depend on external agents for pollination.
• Seedless varieties of plants can be grown by this method.

Drawbacks

• No genetic variation possible so there is weakening of plants over time.
• Plants are more susceptible to diseases and pests.
• There is overcrowding of plants near the parent plant which leads to deficiency of nutrients.

Explanation of Solution

Reproduction through cuttings is a method of vegetative propagation. It is an asexual method in which vegetative part of plant such as stem, root or leaf is used to develop a new plant. Growing plants by the method of cutting is an artificial method of vegetative propagation. In this process a part of stem is taken and planted in soil. After some days roots develop from the base of the stem. New shoots arise and a new plant is formed. Many plants such as rose, banana, potato, jasmine etc are propagated by this method. There are many advantages and disadvantages of this method.

Advantages- It is beneficial for those plants that do not produce seeds such as banana.

Such plants can be grown in quick succession as there is no seedling phase and plants mature faster. So the farmers can grow more crops quickly. The desirable traits in parent plants are preserved and unwanted traits are removed. Since the method produces genetically identical plants, the new plants have all the desirable traits of the parent plant. This method produces clones of parent plant. So this is an added advantage to farmers/ horticulturists who want to grow high quality plants and want to maintain consistency in quality of plant/ crop.

Disadvantages- Vegetative propagation method produces exact copies of parent plant so there is no gene variation. This has an impact on the overall biodiversity of a species. If a certain plant is prone to diseases it may lead to loss of entire crop due to diseases. There is a chance of competition for nutrients amongst the plants propagated vegetatively as they are grown very close to each other.