  We calculate the leading-order scattering amplitude of one vector and two
tensor gauge bosons in a recently proposed non-Abelian tensor gauge field
theory and open superstring theory. The linear in momenta part of the
superstring amplitude has identical Lorentz structure with the gauge theory,
while its cubic in momenta part can be identified with an effective Lagrangian
which is constructed using generalized non-Abelian field strength tensors.
