Robert M. Price thinks that what is sown were the disiepta membra of the Man of Light or Primal Man, dismembered by the demonic archons to give life to a matter otherwise dead forever.
So, in this interpretation, the Sower would be really the evil demiurge, the god of the Jews, since he had any interest to give life to the his stupid creation by sowing the fragments of Light of the Primal Man.
Now, I note a very curious and surprising "coincidence" too much impossible to be such:
Listen! A farmer went out to sow his seed.
(Mark 4:11)
The sower is a σπείρων, the “sower”, the “scatterer”, but it may be a subtle allusion to the “dismemberer” par excellence, i.e. the evil Demiurge who dismembered the Man of Light in the Gnostic Myth. The great surprise is that we find it in the following passage:
The soldiers took Him away into the palace (that is, the Praetorium ), and they called together the whole Roman cohort.
(Mark 15:16)
Why were the best candidates, in Mark, to execute an earthly dismembering of Jesus, just the Roman σπεῖρα ?
In this way, by dismembering the body of Jesus (flagellation), the soldiers of the σπεῖρα work (without knowing it) as the Sower (σπείρων) of the Parable, and accordingly as the Demiurge of the Gnostic myth: by the act itself of dismembering Jesus, they are really sowing his disiepta membra in the entire world.