Host in Nutrition of Plants

In the NCERT Solutions extra questions of Chapter 1 Science (Nutrition in Plants) for Class 7, one of the key concepts is the host. Let's discuss what is meant by a host in the context of plant nutrition.

Definition of Host

A host is a living organism that provides a home or habitat for another organism. In the context of plant nutrition, a host plant is a plant that provides a habitat for another organism, such as a parasite or symbiont.

Types of Hosts

There are two types of hosts in the context of plant nutrition: the primary host and the secondary host.

Primary Host

The primary host is the plant that is initially infected or colonized by a parasite or symbiont. The primary host is essential for the parasite or symbiont to complete its life cycle.

Secondary Host

The secondary host is a plant that is colonized by a parasite or symbiont after the primary host. The secondary host is not essential for the parasite or symbiont to complete its life cycle, but it can provide a suitable environment for the parasite or symbiont to grow and reproduce.

Examples of Hosts

Some examples of host plants include:

- Legumes are host plants for Rhizobium bacteria that fix nitrogen in the soil.
- Grasses are host plants for endophytic fungi that help protect against herbivores.
- Wheat is a host plant for the rust fungus that causes wheat rust disease.

Conclusion

In conclusion, a host plant is a living organism that provides a habitat for another organism, such as a parasite or symbiont. There are two types of hosts: the primary host and the secondary host. Examples of host plants include legumes, grasses, and wheat.

The organism which lives on other organism to fulfill their needs of food and shelter are called parasites and the organism from which they drive their food is called the host. Example - cuscuta plant