Germination of seed is natural
process it also depends upon on some physical and chemical properties of soil.
Germination occurs when a spore
or seed
starts to grow.
It is a term used in botany. When a spore or seed germinates, it produces a shoot
or seedling,
or (in the case of fungi) a hypha. The biology
of spores is different from seeds.
A spore germinates if and
when conditions are right. It has a very limited lifespan. The method of
spore-bearers, which are lower plants such as mosses, ferns and also fungi, is to produce vast
numbers of spores, of which only a small percentage germinate.
Seeds contain an embryo,
a store of food (the endosperm), and a protective coat. Seed plants include Gymnosperms
(such as conifers) and Angiosperms
(such as flowering plants). Seeds can survive much longer than spores, sometimes for
hundreds of years. The strategy of seed-bearing plants is to invest energy and
material in the substance of seeds, and they have evolved more sophisticated
methods of dispersal than just wind.
Seeds do not germinate until their
requirements are met, and these needs differ from species
to species.
1.
The dormancy period must be
over. Dormancy is governed by changes inside the seed. Each species has its own
dormancy period, and will not germinate until that period is over.
2.
Their hibernation must be
over. The hibernation is ended when events in the environment trigger
germination. Sometimes this is just temperature and water, sometimes fire,
sometimes the seed must go through a long cold spell.
The requirements for fruits
is the same as for seeds. A fruit is just a seed with one or more extra layers
derived from parts of the flower.
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