Primary energy spectral models are tested in the energy range of 1–200 PeV using standardized extensive air shower responses from BASJE-MAS, Tibet, GAMMA and KASCADE scintillation shower arrays. Results point toward the two-component origin of observed cosmic ray energy spectra in the knee region consisting of a pulsar component superimposed upon rigidity-dependent power law diffuse Galactic flux. The two-component energy spectral model accounts for both the sharp knee shower spectral phenomenon and observed irregularity of all-particle energy spectrum in the region of 50–100 PeV. Alternatively, tested multipopulation primary energy spectra predicted by nonlinear diffusive shock acceleration models describe observed shower spectra in the knee region provided that the cutoff magnetic rigidities of accelerating particles are $6\pm 0.3$ and $45\pm 2\mathrm{PV}$ for the first two populations, respectively. Both tested spectral models confirm the predominant $H-He$ primary nuclei origin of observed shower spectral knee. The parameters of tested energy spectra are evaluated using solutions of the inverse problem on the basis of the corresponding parameterizations of energy spectra for primary $H$, $He$, $O$-like and $Fe$-like nuclei, standardized shower size spectral responses in the $550–1085\mathrm{g}/{\mathrm{cm}}^2$ atmospheric slant depth range and near vertical muon truncated size spectra detected by the GAMMA array.

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