ON THE SEMIHARD HADRONIC-INTERACTIONS IN EXTENSIVE AIR SHOWER

A consistent scheme to incorporate the semihard processes into Gribov- Regge models of hadronic interactions is proposed. Particle production during the soft preevolution, before the hard parton-parton scatterin g, is explicitely taken into account. Perturbative parton cascade is d escribed on the basis of the unified evolution equation. The effect of the unitarization of the hard partonic scattering amplitude is discus sed. Some consequences for Extensive Air Shower development and for EA S data analysis are considered.