Apomixis & Polyembryony

Apomixis is a special mechanism, to produce seeds without fertilization. It is a form of asexual reproduction that mimics sexual reproduction.

Ways of  Formation of apomictic seeds :

1)  A  diploid egg cell (formed without meiosis)  develop into embryo without fertilization

2) Cells of nucelus (2n) surrounding embryo sac  protrude into embryo sac and  develop into embryos. Ex. Citrus and Mango.

 

Polyembryony : Occurrence of more than one embryo in a seed

It is often associated with apomixes.  Ex: Citrus, groundnut.