The connection between the spatial gradient of the equivalent vertical total electron content (Ntot) of the ionosphere and scintillation patches are examined. It is shown that in the evening hours under quiet geomagnetic conditions, a steplike gradient of Ntot with latitude develops at the northern edge of the main ionospheric trough. Later in the evening, the above structure moves southward and the latitudinal gradient of Ntot becomes very pronounced and around it a scintillation patch is formed. During magnetic disturbances, the monotonic sharp gradient Ntot is destroyed. A number of maxima of total electron content which become collocated with many scintillation patches are formed. Further, under disturbed conditions, the power law index of both the amplitude and phase scintillation spectra shows a marked variation with latitude which may be quadi-periodic.