Definitely not the direction I would've taken the holes theme, and that's great to see! This is unique to anything I've seen in the jam so far, and it's fun for it! It plays like a standard third person shooter, and is quite fun for what it is! The graphics are nice, especially the cacti, which are great to look at. I personally would've liked to see the holes used a bit more (perhaps guns appearing from wormholes), and the dialogue to skip itself if you die and replay the game, though you see it infrequently enough that it isn't a problem, and perhaps background music. It's a short game, but regardless, it's definitely a fun one!
Also just a brief thing I noticed coding-wise: when you move diagonally, the farmer moves faster, as he's moving both horizontally and vertically at the same time. You can fix this by using the Vector3 value of his motion, normalized and then times the speed value, so for example
new Vector3 (horizontalSpeed, verticalSpeed, 0).normalized * Speed * Time.deltaTime;
You might've just forgotten, or perhaps you didn't know - it certainly doesn't make the game any worse, it's still very fun, but probably worth a mention.