DEVELOPMENT OF SEED

After double fertilization the ovule is develop into seed during the seed development following charges occur .

The diploid zygote develop into the embryo by a number of mitotic division . The embryo consist of the radicle . The plumule on whether the plant is monocotyledon or dicotyledon .

As the embryo reaches maturity its further growth is the suspended due to formation of growth inhibitors.

The triploid primary endosperm nucleus develops into the endosperm by a number of mitotic cell division. The endosperm provided nourishment  to the embryo .

Depending on the presence or absence of the endosperm .

The nucellus is generally used up by the developing embryo but in some seeds it persists in the form of a thin layer around the endosperm this residual nucleus is known as perisperm or nucellus.

 

The seed are two types

1- Endospermic seed or Albuminous seed

When the endosperm persists in the seed as food storage tissue these seed are called endospermic seed.

Example - maize, wheat, barley , rubber, rice , etc 

2- Non-endospermic seed 

When the endosperms is completely eaten up by the growing embryo such type of seed is called non-endospermic seed .

Example- pea, gram , bean ground nut