String corrections to gauge couplings from a field theory approach
  An effective field theory approach is introduced to compute one-loop radiative corrections to the gauge couplings due to Kaluza-Klein states associated with a two-torus compactification. The results are compared with those of the string in the field theory ``limit'' alpha'-> 0. The whole U and the leading T moduli dependence of the gauge dependent part of the string corrections to gauge couplings can be recovered using the effective field theory approach. 
D.M. Ghilencea, S. Groot Nibbelink