We have investigated spontaneous emissions from a two-level atom embedded in a p hotonic crystal with three-dimensional dispersion relation as well as interacted with a coherent intense low-frequency field .Due to this field, additional deca y channels with exchange of one low-frequency photon during an atomic transition are created, resulting in the spontaneously induced quantum interference. The s pontaneous emission can be suppressed significantly because of the combinational influences of the quantum interference effect and the band edge effect. The pop ulation in the upper levels depends on the relative position of the upper level from the band edge. The frequency of the low-frequency field and the relative in tensity of the coupling strength for the transitions can affect spontaneous emis sion from the atom.