One-Loop MHV Amplitudes in Supersymmetric Gauge Theories

Using CSW rules for constructing scalar Feynman diagrams from MHV vertices, we compute the contribution of $\mathcal {N}=1$ chiral multiplet to one-loop MHV gluon amplitude. The result agrees with the one obtained previously using unitarity-based methods, thereby demonstrating the validity of the MHV-diagram technique, in the case of one-loop MHV amplitudes, for all massless supersymmetric theories.