  We consider the observational constraints from the detection of antiprotons
in the Galaxy on the amount of Primordial Black Holes (PBH) produced from
primordial power spectra with a bumpy mass variance. Though essentially
equivalent at the present time to the constraints from the diffuse $\gamma$-ray
background, they allow a widely independent approach and they should improve
sensibly in the nearby future. We discuss the resulting constraints on
inflationary parameters using a Broken Scale Invariance (BSI) model as a
concrete example.
