A F2 hybrid is a second-generation cross between two F1 hybrids.
Some hybrids are sterile and it is impossible to get seed from them,
while other hybrids are self- fertile.

True species × Hybrid = F2 hybrid with inconsistent characteristics.

Hybrid × Self (own pollen) = F2 hybrid with inconsistent
characteristics.

Hybrid × same Hybrid = F2 hybrid with inconsistent characteristics.

An F1 hybrid gives hybrid vigour and an F2 hybrid the most variable
offspring which diminishes as the number of the F increases. Seed
obtained from above can produce some remarkable plants, but a large
percentage of them are weak and therefore not worth growing.

F1 hybrid - is the first generation of a cross between any two
unrelated seedlines in the creation of a
hybrid. F1 hybrids can be uniform or variable depending on the P1
parent stock used.

F2 hybrid - is the offspring of a cross between two F1 plants

Hope that was not too confusing

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