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The QCD sum rules in the large-$N_c$ limit for the light non-strange vector,axial and scalar mesons are considered assuming a string-like linear spectrumfor the radially excited states. We propose a improved method for combinedanalysis of these channels that gives a reasonable description of the observedspectrum. In the vector-axial case, fixing the pion decay constant and thegluon condensate we obtain more or less physical values for the masses ofground states and the quark condensate. Thus a typical need for this method tofix the mass of some ground state is overcome. Using in the scalar channel thevalues of presumably universal slope of radial trajectories and the quarkcondensate obtained in the vector-axial channel, we find that, in contrast tosome strong claims in the literature, a prediction of light scalar state with amass close to the mass of $f_0(500)$ seems to be natural in the consideredapproach and may follow in a natural way from the Regge phenomenology.

The sigma meson from QCD sum rules for large-$N_c$ Regge spectra