Question

Seeds of some plants germinate immediately after shedding from the plants while in other plants they require a period of rest before germination. The later phenomena is called as dormancy. Give the reasons for seed dormancy and some methods to break it.

Answer 1

Reasons for seed dormancy:

• Seed coats are tough.

• Water cannot be absorbed through impermeable layers.

• ABA slows germination and restricts development.

• Certain seeds have an underdeveloped embryo, which causes germination to be delayed.

Methods to break seed dormancy:

• Temperature as well as other environmental factors can cause physical dormancy to be disrupted. When a seed goes through the intestines of an animal, it loses its physical dormancy.

• External factors assist in breaking mechanical dormancy. An animal, for instance, could fracture the hard seed covering.

• Enzymatic activities break chemical dormancy.