  A model is developed for electromagnetic form factor of the pion. One-loop
corrections are included in the linear sigma-model. The rho-meson contribution
is added in an extended VMD model. The form factor, calculated without fitting
parameters, is in a good agreement with experiment for space-like and time-like
photon momenta. Loop corrections to the two-pion hadronic contribution a^{(had,
\pi)}_\mu to the muon anomalous magnetic moment are calculated. The optimal
value of the sigma-meson mass appears to be close to the rho-meson mass.
