What is apomixis? How does it occur, and why is it important for the hybrid seed industry?

How to lay out the answer. Follow the frame, then write it in your own words.

1 · Define in one line. Apomixis is the formation of seeds without fertilisation; it is asexual reproduction that mimics sexual reproduction.
2 · How it occurs.
- A diploid egg forms without reduction division and develops without fertilisation.
- Nucellar cells grow into the embryo sac and form embryos, as in Citrus and mango (polyembryony).
3 · The hybrid seed problem. Hybrid characters segregate in the next generation, so costly hybrid seed must be bought every year.
4 · The apomixis solution. Apomictic hybrids show no segregation, so farmers could keep using their own hybrid seed.
5 · Close in one line. So scientists are trying to transfer apomictic genes into hybrid crop varieties.

Scoring tip: Use the word 'segregation'; it is the key idea examiners look for in the hybrid seed part.