Virtual-Sparticle Threshold Effects on Large E_T Jet Cross Sections

We discuss the one-loop virtual-sparticle corrections to QCD jet cross sections at large $E_T$ and large dijet invariant masses, with reference to present Tevatron and future LHC collider experiments. We find characteristic peaks and dips in the sparticle threshold region, due to interferences with tree-level QCD diagrams. Their magnitudes may be several per cent of the total jet cross section, so they might provide a useful search tool that is complementary to the usual missing-energy signature for supersymmetry.