Measurement of Growth

Growth in plants can be measured in terms of....

1. Increase in cell number -- e.g. a single maize root apical meristem can give rise to more than 17,500 new cells per hour.
2. Increase in leaf surface area -- as seen in the growth of a dorsiventral leaf.
3. Increase in length -- as seen in the growth of a pollen tube.
4. Increase in volume of a fruit -- e.g. in a watermelon flower, the ovary can increase in volume by up to 3,50,000 times after fertilisation.
5. Increase in girth of the shoot.
6. Increase in dry weight of an organ.

Various methods for the measurement of linear growth of stem and radicle are as follows:

1. Direct method : -- growth is measured simply with an ordinary measuring scale; quick but not very precise.
2. Horizontal microscope : -- used to measure growth of plants in the field.
3. Auxanometer : -- used for precise measurement of the linear growth of a shoot; two common types are the Arc auxanometer and Pfeffer's auxanometer. …