Question

The adventitious embryo in Citrus is formed from

• A. nucellus
• B. egg apparatus
• C. zygotic embryo
• D. fertilized egg

Answer 1

The correct option is A nucellus

Adventitious embryony is also called nucellar embryony or nucellar budding. The embryo does not develop from the cells of the embryo sac but develops from the cells of either the nucellus or integuments. This type of embryo is common in tropical and subtropical species of Citrus, mango, etc. So, Citrus’s adventive embryo is formed from the nucellus.
Three cells inside the embryo sac at the micropylar end constitute the egg apparatus, which in turn, consists of one egg cell and two synergids.
Fertilisation is the fusion of the male and the female gametes inside the ovule forming a diploid zygote.
The zygotic embryo is formed following fertilisation of the ovule, which undergoes a series of differentiation events, leading to the formation of a mature embryo.