I suspect that you may have those wide tires on a fairly narrow rim. That can cause tubes to fail on the rim side, as described below.

The tire forms an Omega shaped cross-section, which is pinched in at the bottom by the rim. There's a gap between the tire beads at the bottom, with more room below.

When you first start pumping the tube it assumes a circular profile as in the sketch below.

As you increase pressure, the section spanning the gap blows down to fill the space below the beads (above in the sketch) stretching more than the rest of the tube. On very narrow rims, this additional stretch is more than the material can tolerate and leads to small tears.

Your photo didn't show the whole tube, but you'll often see evidence of that additional stretch along the belly of the dead tube.

Using talc inside the tire helps the rube slip and equalize the stretch a bit. My solution is to use the widest tube that fits the tire. That way it's less stretched in the first phase, and has more stretch left over to blow down past the narrows.

Patching on the belly is problematic for the same reason. That area stretches more than average, and is therefore more likely to teat a poorly adhered patch off.