In the laboratory experiment, we examined the insecticidal activity of three zeolites (natural 'Zeolite Slovenia' and 'Zeolite Serbia' and the synthetic zeolite 'Asorbio') for the control of adult specimens of maie weevil (Sitophilus zeamais). In the first part of the experiment we examined the contact activity of inert powders, while in the second part we studied the activity of inert powders mixed with wheat grains. The selected powders were used in various concentrations, which represented individual treatments. As a positive control we used the preparation of the diatomaceous earth 'SilicoSec®', while the negative control was made up of Petri dishes and bottles without any powders. Insecticidal activity of selected powdered preparations was studied in a growth chamber at different temperatures (15, 20 and 25 °C) and at two different values of relative humidity (55 and 75%). In the first part of the experiment, the mortality of weevils was determined on the 1st, 2nd, 3rd, 4th and 7th day after the experiment was set, and then on 8th, 9th, 10th, 11th and 14th days the mortality of weevils were determined with delay. In the second part of the experiment, the mortality of weevils was determined on the 7th, 14th and 21st days after the experiment was set. In the first part of the experiment, the highest mortality was recorded in 'Zeolit Slovenia' and 'SilicoSec®', while in the second part of the experiment, 'Zeolit Serbia' and 'SilicoSec®' were examined. The highest insecticidal effect of the studied inert powders was achieved with a combination of higher temperature and lower relative humidity after the longest time exposure. The influence of concentration on the contact inert powders was not recorded. In the second part of the experiment where we studied the action of inert powders mixed with wheat grains, we confirmed in all treatments the highest mortality of weevils at higher concentrations.
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