Question

Students were on an excursion to a botanical garden. They noted the following observation. Will you be able to help them in understanding those condition?

A plant was found growing on other plant. Teacher said it is not a parasite. It exhibited two types of roots.

Answer 1

• Student must have observed an epiphytic plants like Dendrobium, Vanda growing on other plant.
• The two types of roots exhibited by this plant must be clinging roots and epiphytic roots.
• Clinging roots:

1. Clinging roots are tiny roots develop along internodes, show disc at tips.
2. It exudes sticky substance which enables plant to get attached to the substratum without damaging it.

• Epiphytic roots: 

1. Epiphytic plants like Vanda, Dendrobium grow on branches of trees in dense rain forests and are unable to obtain moisture from soil.
2. Such plants produce epiphytic roots which hang in the air.
3. The roots are provided with a spongy membranous absorbent covering of the velamen tissue.
4. The cells of velamen tissue are hygroscopic and have porous walls, thus they can absorb moisture from air.
5. Epiphytic roots can be silvery white or green and are without root cap.