What are the causes of seed dormancy and how can it be removed?

(N/A) Causes of Seed Dormancy:
$1$. Underdeveloped embryo: The embryo may not be fully mature at the time of seed dispersal.
$2$. Impermeable seed coats: The seed coat may be impermeable to water or oxygen,preventing the necessary metabolic processes for germination.
$3$. Mechanically resistant seed coats: Hard seed coats physically restrict the expansion of the embryo.
$4$. Presence of germination inhibitors: Chemicals like Abscisic acid $(ABA)$ inhibit germination by suppressing gene transcription and enzyme synthesis.
$5$. Absence of growth promoters: $A$ lack of sufficient Gibberellins $(GA)$ in dormant seeds prevents the initiation of germination.
Methods to Remove Seed Dormancy:
$1$. Natural removal: When the concentration of Gibberellins increases and exceeds that of $ABA$,the inhibitory effect is neutralized,and the embryo becomes active.
$2$. Mechanical scarification: Lightly scraping the seed coat with sandpaper or other abrasive materials makes it permeable to water and gases.
$3$. Chemical scarification: Using specific chemicals to soften or break down the hard seed coat.
$4$. Temperature treatment: Exposing soaked seeds to specific high or low temperatures for a defined period can break dormancy.
$5$. Oxygen availability: Providing an oxygen-rich environment to soaked seeds can also help in overcoming dormancy.