  We present the results of the experimental study of the influence of dusty
structures on plasma. We have studied glow discharges in neon and argon with
$\text{Al}_2 \text{O}_3$ polydisperse particles and melamine-formaldehyde
monodisperse particles with the diameter of $\text{4.83} \; \mu m$. We used
optical emission spectroscopy and laser-induced fluorescence methods to measure
shift of excited atoms populations, which led to similar results. In most
cases, the population change was negligible as compared to the inaccuracy.
$\text{Al}_2 \text{O}_3$ particles in argon formed large structures which
caused dramatic redistribution of radiation. In this case, spectral lines and
fluorescence became 9-50% weaker at the tube center after dusty structure
formation. It might be accounted for by a decrease of electron density due to
recombination on the surfaces of the particles. Near the tube wall, the
radiation became brighter due to an electron temperature increase. Photographs
of the discharge allowed us to calculate the radial distribution of the
population shift.
