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प्रश्न
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.
उत्तर
Reasons for seed dormancy:
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Seed coats are tough.
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Water cannot be absorbed through impermeable layers.
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ABA slows germination and restricts development.
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Certain seeds have an underdeveloped embryo, which causes germination to be delayed.
Methods to break seed dormancy:
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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.
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External factors assist in breaking mechanical dormancy. An animal, for instance, could fracture the hard seed covering.
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Enzymatic activities break chemical dormancy.
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