Is there any way I can repair this PVC/conduit that carries sprinkler system wire from the ground into my garage?
There's really only 2 ways to address this issue:

Do it properly and replace that section of conduit. This will require removing the wires, but it is a permanent and visually appealing fix.
Get a split coupling or repair clamp and solvent-weld or fasten it over the damaged area.

Repair Clamp:

Split Coupling: