QCD Corrections to SUSY Higgs Production: The Role of Squark Loops
  We calculate the two-loop QCD corrections to the production of the neutral supersymmetric Higgs bosons via the gluon fusion mechanism at hadron colliders, including the contributions of squark loops. To a good approximation, these additional contributions lead to the same QCD corrections as in the case where only top and bottom quark loops are taken into account. The QCD corrections are large and increase the Higgs production cross sections significantly. 
S. Dawson, A. Djouadi and M. Spira