(i) Apomixis : It is a kind of an asexual process which imitates the sexual reproduction by formation of seed without fertilization. It can be referred to as special type of sexual reproduction which does not involve the process of meiosis and syngamy.
(ii) Parthenocarpy : The formation of fruit without of fertilization is called as parthenocarpy. Such fruits are seedless and called as parthenocarpic fruits. e.g., Banana.
(iii) Polyembryony : The occurrence of plural embryos in a seed is called polyembryony, e.g., citrus fruits like orange. Normally, one embryo is formed in a seed as a result of fertilization but additional embryos may develop apomictly.