In the first part of this thesis the decay of the light stop into a charm quark and the lightest neutralino is calculated at one-loop level in the Minimal Supersymmetric extension of the Standard Model (MSSM) in the framework of Minimal Flavor Violation (MFV). The second part of this thesis covers the calculation of next-to-leading order (NLO) corrections in the strong coupling constant to the pair production of squarks of the first two generations in the MSSM
