Question

What are the main physiological parameters that influence plant growth?

Answer 1

Hint: Growth is defined as an increase in mass or volume of plants with or without the formation of organs of the plants. It is usually associated with the process of reproduction as well as development. It is majorly influenced by a variety of parameters thus it can alter the growth of a plant.

Complete answer:
Growth is regarded as one of the most fundamental and conspicuous characteristics of a living being. It can be defined as an irreversible permanent increase in the size of an organ or its part or even of an individual cell. Generally, growth is accomplished by metabolic processes ( both anabolic and catabolic)that occur at the expense of energy. Therefore, for example, the expansion of a leaf is growth.

Plant growth is unique because plants retain the capacity for unlimited growth throughout their life. This ability of the plants is due to the presence of meristems at certain locations in their body. The cells of such meristems have the capacity to divide and self-perpetuate. The product, however, soon loses the capacity to divide and such cells make up the plant body. This form of growth wherein new cells are always being added to the plant body by the activity of the meristem is called an open form of growth.
There are a number of physiological factors that contribute to the growth of plants.

A few of them are:
- plant hormones and their activity
- respiration
- photosynthesis
- photoperiodism
- germination of seeds,
- rate of transpiration
- dormancy
- environmental stress physiology
- enrichment of soil fertilizer
- efficiency of nutritional usage
- increase in dry and fresh weight
- leaf weight
- increase in the area of leaves
- stem diameter
- volume of the tissues
- increase in the number of cells.

Note: Oxygen, water and nutrients are very essential elements for growth. Water also provides the medium for enzymatic activities that are needed for growth. Oxygen helps in releasing metabolic energy essential for cell growth. Nutrients are required by plants for the synthesis of protoplasm and acts as a source of energy.