Squark Effects on Higgs Boson Production and Decay at the LHC

In the context of the Minimal Supersymmetric extension of the Standard Model, I discuss the effects of relatively light top and bottom scalar quarks on the main production mechanism of the lightest SUSY neutral Higgs boson $h$ at the LHC, the gluon--gluon fusion mechanism $gg \to h$, and on the most promising discovery channel, the two--photon decay mode $h \to \gamma \gamma$. In some areas of the parameter space, the top and bottom squark contributions can strongly reduce the production cross section times the branching ratio.