Slugs cause extensive damage to cultivated and wild plants and are therefore classified as an economically important pest. Since biotic control is a very good alternative to chemical control of economically important pests, we studied the efficacy of the parasitic nematode Phasmarhabditis papillosa on mortality and feeding of slugs from the Arionidae family at different temperatures (15, 20 and 25 °C) and nematode suspension concentrations (0, 500, 1000 and 2000 IL/slug) in a laboratory experiment. In our study, we found that mortality of slugs dependendi on several factors: temperature, nematode suspension concentrarion and duration of exposure to the nematodes. P. papillosa was most effective at T 20°C. The mortality rate of slug was 56% after two weeks, 76% after three weeks and after one month all slugs in the experiment had died. Slugs feeding was also reduced by 67 % at 20 °C after 2 weeks, and infected slugs were no longer feeding after 3 weeks. The efficacy of P. papillosa nematode was porest at 25 °C. There were no differences in the effect on slug mortality between concentrations of 1000 and 2000 IL/slug. Temperature, in combination with the duration of the experiment, had the greatest effect on slug mortality and feeding. The mantles of infected slugs inflated and they rotated 360° around their own axis.
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