In gametophytic system of self-incompatibility, fully compatible will result from a cross between

In the gametophytic system of self-incompatibility, fully compatible will result from a cross between S₁S₂ × S₃S₄.
Gametophytic self-incompatibility, involves the inability of the gametes from the same parent plant to fuse and form a zygote or, if the zygote forms, then it fails to develop. These systems force outcrossing and maintain a wide genetic diversity.
The fully compatible progeny will result from a cross between S₁S₂ × S₃S₄.