Which preposition to use with maturation

of Occurrences 6%

The ovary is the organ for the preservation and maturation of the germ plasm, that treasure which the body is built but to cherish and hand on as a sacred heirloom.

to Occurrences 1%

It is necessary that of every play the chief action should be single; for since a play represents some transaction, through its regular maturation to its final event, two actions equally important must evidently constitute two plays.

Which preposition to use with  maturation