SUMMARYThe established indoor population of introduced Valencia slug, Lehmania valentiana (Ferussac, 1821), has been recorded for the first time in Serbia. The first two specimens had been found in December, 2010 and cultivated in the laboratory by the end of April, 2011 when they died. In May, we collected new specimens of different ages in the same locality, indoor garden of Hyatt Regency Belgrade hotel. In the case of large population densities Valencia slug could cause severe damage to greenhouse plants in our country, yet it is unlikely that it could survive winter outdoor in Serbia, and we do not expect its permanent outdoor establishment.

SUMMARYThe aim of our study was to investigate the possibility of application of essential oils as additives in cereal-based rodenticide baits, at rates which prevent mould development and are applicable in humane medicine. Also, the purpose of these oils would be to extend the utility value of baits and reduce the use of antifungal ingredients that usually affect bait acceptance.The effects of essential oils of ten different plant species, applied at rates of one and two ml per kg of plain bait, on bait acceptance and palatability in choice feeding tests for Swiss mice were studied under controlled laboratory conditions. Baits were prepared according to relevant EPPO standards (2004). The effects of essential oils on bait acceptance and palatability for Swiss mice were determined in choice feeding tests using a formula by Johnson and Prescott (1994).There was no significant statistical difference in effects between groups and sexes regarding weight change in the experiment. During the experiment and recovery period, neither change in mice behavior no deaths were observed. Cinnamon and anise essential oils, commonly used as attractants, and clove oil, were most effective because they had no negative effect on bait acceptance and palatability, while fenchel and bergamot oils showed repellent activity that grew as the oil content in baits increased.

The species complexes of leaf-inhabiting mites on apples were studied on actively cultivated and neglected apple orchards as well as on wild apple trees in Serbia, from 1981 to 2013. Thirty-nine species of 11 families were found on Malus domestica Borkh; 25 species of 6 families were found on Malus sylvestris (L.) Miller and Malus pumila Miller. A complex of 18 phytoseiid and 9 spider mite species was detected. Four phytoseiid and three spider mite species were found in commercial apple orchards, 13 phytoseiid and 5 spider mite species in neglected apple stands, and 12 phytoseiid and 7 spider mite species in forest habitats. Predatory mites Euseius finlandicus (Oudemans) and Amblyseius andersoni (Chant) and spider mites Panonychus ulmi Koch and Amphitetranychus viennensis (Zacher) had the highest constancy of occurrence. Positive and significant (or very significant) association was detected for 16 pairs of species. The pairs of phytoseidsspider mites Amb. andersoni-Pan. ulmi, Amb. andersoni-Tetranychus turkestani Ugarov et Nikolskii, and Typhlodromus (Anthoseius) rhenanus (Oudemans)-Te. turkestani had the highest interspecific association indices. Higher mite diversity was found on wild than on cultivated apples, and higher diversity on neglected than on cultivated apples. The complexes of phytoseiids and spider mites had uniform composition in the cultivated orchards, while their composition in the neglected stands was nonuniform and extremely heterogeneous on the wild apple trees.

SuMMARYDamage caused by the white snail Cernuella virgata (Da Costa, 1778) was for the first time observed in vegetable crops in Serbia during the summers of 2011 and 2012. In this country, serious damage to vegetable crops is usually caused by slugs, while snails do not normally cause any significant harm. Typical xerophilic snail species in the genera Cernuella, Xerolenta and Theba cause damage even more rarely since they are limited to wild flora in uncultivated and ruderal areas, and local outbreaks occur seldom and only in forage leguminous crops. The species C. virgata was for the first time found to cause damage to a number of vegetable crops during long periods of extremely warm and dry weather, including total devastation of a green onion crop.

The effect of cinnamon (Cinnamomi zeylanicum) and clove (Eugenia caryophyllata) essential oils on the acceptibility of cereal-based baits to house mice in storage facilities was examined. The effects of three concentrations, 0.5, 0.75 and 1 %, were tested for optimization purposes. The experiments were performed in a mill storage, and in another storage for seeds and seedlings. Attractiveness of the examined concentrations of cinnamon and clove essential oils was statistically significant, compared to placebo bait, within seven days of the experiment. On the seventh day, the average consumption of baits containing 0.75 % and 1 % concentrations of cinnamon oil was 46 % in the mill storage, i.e. 35.5 % more than placebo baits were consumed. Fourteen days after the beginning of the experiment, no significant difference was detected in the consumption of baits offered in the mill storage. On the other hand, a significant difference was revealed regarding the consumption of examined baits in the seed and seedling storage. The average consumption of baits containing 0.75 % and 1 % cinnamon oil was 47 % and 51 % higher after 14 days than the consumption of placebo bait. Compared to the other test baits, those containing cinnamon essential oil at 0.75 % and 1 % concentration demonstrated better attractiveness without mutual statistically significant differences.