The silicoflgellate species Distephanopsis concavus Horvat is revised based on further research of the type material. This species is characterized by having a basal ring with strongly concave sides ...which reduce the basal ring area and by four symmetry planes which are morphological characteristics not known in other Distephanopsis species. The species was found in Middle Miocene deposits of the Central Paratethys. Its occurrence at type locality in SE Slovenia is dated to late Middle Badenian and is correlated to the upper part of the nannoplankton biozone NN5.
V preglednem članku se osredotočamo na alternativni pristop varstva krompirja (Solanum tuberosum) pred koloradskim hroščem (Leptinotarsa decemlineata), ki pri nas in v svetu velja za najpomembnejšega ...škodljivca te pomembne poljščine. V prispevku predstavljamo uporabo različnih inertnih prahov za zatiranje tega škodljivca. Osredotočili smo se na kategorizacijo prahov, predstavitev posameznih skupin inertnih prahov in opis ene ali več snovi, ki pripadajo specifični skupini. Poleg splošne predstavitve načinov delovanja posameznih prašiv navajamo tudi praktične zglede uporabe prašiv proti koloradskemu hrošču, s čimer želimo predstaviti potencial različnih prašiv za uporabo v praksi. Ugotavljamo, da veljata lesni pepel in diatomejska zemlja za bolj perspektivna inertna prahova pri zatiranju škodljivih žuželk. Lesni pepel učinkovito deluje proti ličinkam ter v manjši meri tudi na odrasle osebke, diatomejska zemlja pa prav tako vpliva na zmanjšanje številčnosti koloradskega hrošča na krompirju. Ostala inertna prašiva so v strokovni literaturi izpostavljena kot manj učinkovita oz. sploh še niso bila preizkušena ali uporabljena proti temu škodljivcu. Za dokončno določitev učinkovitosti prašiv bodo potrebne nadaljnje raziskave, tako v laboratorijskih razmerah kot na prostem.
The Colorado potato beetle (CPB) is an economically important pest on potatoes, which can cause significant damage if not controlled. Our laboratory trial was conducted to study the efficacy of five ...types of inert dusts (diatomaceous earth, quartz sand, Norway spruce wood ash, zeolite, and tree of heaven leaf dust) against the CPB. Efficacy was tested using three modes of application (MoA): MoA 1, in which the used inert dusts were applied to both leaves and insects; MoA 2, where just the leaves were pre-dusted; and MoA 3, where only the pests were pre-dusted. All three modes were tested on larvae (L1/L2 and L3/L4) and adults of CPB. Among the inert dusts applied to the adults, the highest efficacy was recorded for the diatomaceous earth treatment (13.3 ± 3.3%) in the first MoA and the wood ash treatment (6.7 ± 3.3%) in the second MoA after 7 days of exposure. Defoliation results for adults were most promising in the A. altissima leaf dust treatment in the first and second MoA (45.3 ± 8.2%) after 7 days of exposure. For the old larvae, wood ash was the most promising in regards to efficacy (26.7 ± 7.3%) and defoliation (app. 70.0%) after 7 days of exposure in the third MoA. For the young larvae, the most promising results at the end of the 7-day exposure period for efficacy were obtained from the treatment of diatomaceous earth (65.7 ± 22.9%). Defoliation rates for young larvae were also high, but most promising in the treatment of A. altissima leaf dust (41.0 ± 4.2%) in the second MoA. The results showed that the inert dusts were not very effective in controlling the CPB, with the exception of wood ash and diatomaceous earth, which showed some limited control. A. altissima leaf dust generated a low defoliation rate, possibly due to an antifeedant effect on the beetles.
In a laboratory experiment, we studied the insecticidal effects of invasive alien plants on the rice weevil. The research was carried out in two parts. In the first part, we studied the insecticidal ...properties of seven different plant species, namely, Bohemian knotweed (Fallopia × bohemica), Japanese knotweed (Fallopia japonica), false indigo-bush (Amorpha fruticosa), tree of heaven (Ailanthus altissima), staghorn sumac (Rhus typhina), Canada goldenrod (Solidago canadensis), and giant goldenrod (Solidago gigantea). Mixtures of powders and wheat were prepared in two different concentrations, namely, 2.5 w% and 1.25 w%. The experiment was performed at temperatures 20 °C and 25 °C and at two humidity levels, 55% R.h. and 75% R.h. Very low mortality (below 8%) was found when using combinations with the higher relative humidity. No significant differences were observed between the effects of these concentrations. In the second part of the experiment, Norway spruce wood ash and diatomaceous earth (product SilicoSec®) were added to the powder obtained by milling leaves of four different invasive plant species (Canada goldenrod, staghorn sumac, tree of heaven, false indigo). In the independent application, wheat was added to the powder at a concentration 2.5 w%. In the treatments that involved mixtures of powder and wood ash/diatomaceous earth, we applied 1.25 w% plant powder and 1.25 w% wood ash or 1.25 w% plant powder and 450 ppm of a SilicoSec® preparation. The positive control was carried out as two separate treatments with 2.5 w% wood ash of Norway spruce and 900 ppm of the SilicoSec® product, while untreated wheat represented the negative control. The experiment was performed at two temperatures (20 °C and 25 °C) and two R.h. values (55 and 75% R.h.). The mortality of beetles was recorded on the 7th, 14th, and 21st day after the start of the experiment. Higher mortality rates of rice weevil adults were found at the higher relative humidity, and an important factor of mortality was also the day of exposure, as a higher mortality was found when the exposure of individuals to the tested substances was for a longer time period. After 21 days at 25 °C and 55% R.h., the combinations in which the lower concentration of Norway spruce wood ash was added to the powder of invasive alien plants achieved more than 90% mortality of beetles. By adding the plant powder of invasive alien plants to wood ash, we achieved a greater insecticidal efficacy of invasive plants and lower concentrations of wood ash. Nevertheless, the results of our research do not indicate any great usefulness of the plant powder of invasive plants in suppressing the rice weevil. Additional studies should primarily focus on the insecticidal efficacy of powder from the genus Solidago, which in our study, displayed the greatest insecticidal potential among the tested invasive plants.
The wood ash from seven plant species (sessile oak, European beech, European hornbeam, silver fir, European spruce, common alder, and Spanish chestnut) was tested against Spanish slug (Arion ...vulgaris) as an environmentally acceptable alternative to chemical bait pellets. We carried out laboratory and semi-field experiments to assess the contact and barrier efficacy of selected wood ash. To demonstrate the contact efficacy, slugs were rolled in the wood ash. Geochemical analysis of wood ash was carried out as well. The highest concentrations of chemical compounds SiO2, Al2O3, Fe2O3, MgO and MnO and elements Ba, Co, Cs, Ga, Cu, Pb and Zn were identified in the most effective ashes (beech, oak, fir, and spruce) compared to the ineffective ashes (hornbeam, chestnut, black ader). The concentration of cobalt was comparably higher, while the concentration of molybdenum was comparably lower in the four most effective wood ashes. The results of our studies revealed that the wood ash of oak and spruce have great contact efficacy. The oak and beech wood ash showed the strongest barrier efficacy against slugs. In the semi-field trials, only 10% of the plants treated with oak wood ash were damaged by slugs. The oak wood ash is an efficient alternative for slug control, however, further studies and biotechnical enhancement are needed.
A carbonate cobble was collected in a creek near Slovenj Gradec (Slovenia). It comprises Trochactaeon gastropods as well as foraminifera Fleuryana adriatica and Cuneolina ketini from a subtidal ...environment with agglutinated and porcelaneous benthic foraminifera. Packstone-grainstone of the structural type contains the abovementioned foraminiferal taxa, which are previously undetermined in this part of the Upper Cretaceous Tethyan realm. Stratigraphic data from this area, together with the determined microfossil assemblage of the carbonate cobble, indicate the upper part of Lower Campanian age, implying an extension of the F. adriatica and C. ketini stratigraphic range. The paleoniche within the Tethyan realm in which F. adriatica thrive is the shallowest part of the subtidal, close to peritidal conditions. It was developed on a relatively harder substrate that resulted from a laterally more pronounced paleorelief which enabled the shifting of hyaline benthic foraminifers towards the shallowest part of the subtidal. Their paleoniche is laterally absent from protected paleoenvironments with soft muddy substrate and a relatively high carbonate sedimentation rate, colonized with elevator rudists, as well as from relatively higher water energy paleoenvironments with completely hard grainstonerudstone substrate.
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Areas around seaports are prone to environmental damage. In the port of Koper, Slovenia hematite was transhipped during a strong wind. The broader area was accidentally covered with hematite dust. ...Since the soils had already been geochemically mapped, we repeated the sampling to compare the geochemical composition of the topsoil. No soil contamination was established. The enrichment factors show depletion of majority of elements. According to the distances from the dust source, SiO2, Na2O and Cr have decreasing, and Fe2O3 increasing trends. The SiO2 and Cr content correspond to the concentration of quartz rich sand, and the dissolution of carbonate closer to the sea. Co and Ni are probably bound to the clay minerals. Cu, Pb, and Zn could have some anthropogenic contribution.
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In the Middle Miocene the area of present-day eastern Slovenia was situated at the eastern mouth of the Slovenian Corridor – a hypothetical seaway connecting the Central Paratethys and the ...Mediterranean. The exact location and time of closure of a seaway between the two neighbouring marine realms are still a matter of debate. We studied Badenian (late Langhian and early Serravallian) calcareous nannoplankton assemblages from eastern Slovenia for their palaeogeographical significance by comparing them to contemporaneous Central Paratethyan and Mediterranean assemblages and the assemblages described in selected ODP and IODP reports. Assemblage composition and the sequence of biostratigraphic events observed in Slovenia were very similar to that in several Mediterranean sites. Comparison with the World Ocean suggests that this similarity reflects communication between the Mediterranean and Paratethyan populations rather than a universal trend of nannoplankton evolution.
Late Badenian assemblages from different localities within the Central Paratethys exhibit considerable variation with respect to the presence of discoasters (considered as typical of the Mediterranean) and the presence of Rhabdosphaera poculi and Hayella challengeri (considered as typical of the Eastern Paratethys). Our results suggest the mixing of Mediterranean and Eastern Paratethyan influences throughout the entire Central Paratethys during the late Badenian. The observed variability explains how opposing views on the status of the marine connection between the Central Paratethys and the Mediterranean in the late Badenian can arise from palaeontological studies of fossil assemblages considering only a single site or a small area.
The gastropod species Pereiraea gervaisi migrated from the Mediterranean to the Central Paratethys – where it is only known from the immediate proximity of the hypothesised Slovenian Corridor. This supports the thesis that the communication between the two seas took place via the Slovenian Corridor and not some other marine connection like the hypothetical Axios (Vardar) Trench.
•Did the Central Paratethys and the Mediterranean communicate in early Serravallian?•Paleontological evidence from eastern Slovenia (C. Paratethys) suggests that they did.•P. gervaisi distribution in Central Paratethys indicates site of marine connection.•Contradictions in previous works result from considering single sites only.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Diatomejsko zemljo uporabljajo v številne namene, med drugim tudi kot bioinsekticid za varovanje uskladiščenih pridelkov. Ta zemlja nastane z mletjem sedimentnih kamnin, imenovanih diatomiti. Obstaja ...veliko vrst diatomejske zemlje, a le zemlje z manj kot 7 % kristalnega SiO2 so primerne za zatiranje škodljivcev. Diatomejska zemlja ni toksična za sesalce, dolgotrajno varuje živež pred škodljivimi žuželkami, za njen nanos se uporablja približno enaka tehnologija kot pri klasičnem nanosu insekticidov in se med predelavo zlahka odstrani z živeža. Med nekaj negativnimi lastnostmi gre izpostaviti dejstvo, da zmanjša hektolitrsko maso zrnja (zniža nasipno gostoto zrnja), ki je glavno merilo kakovosti zrnja. Diatomejska zemlja ima velik absorpcijski potencial in se veže na epikutikularne voske žuželk, zato deluje praktično na vse škodljivce, ki imajo kutikulo zaščiteno z voski.
Laboratory experiments were carried out to evaluate the impact of zeolites of different origins on the mortality of the maize weevil (Sitophilus zeamais Motschulsky). We tested the efficacy of ...natural zeolites (Slovenian and Serbian) and a synthetic zeolite (Asorbio®). Diatomaceous earth (SilicoSec®) was used as a positive control. We applied the zeolites as surface treatments (at concentrations of 10 g/m2 and 20 g/m2) and as admixtures (grain with zeolites) (at concentrations of 450 ppm and 900 ppm). The mortality of the weevils when the zeolites were applied as a surface treatment was evaluated every day until the 7th day after application; delayed mortality was measured every day until the 14th day after application. When the zeolites were admixed, we evaluated mortality after the 7, 14, and 21 days. The research was performed at two different relative humidity values (55 and 75%) and at three different temperatures (15, 20 and 25 °C). We conclude that the mortality of maize weevils was influenced by relatively high temperature and low relative humidity values. There was no impact of the zeolite dose on the mortality of the maize weevils when applied as a surface treatment. The mortality of the weevils was similar in the treatments with the two natural zeolites (Slovenian and Serbian), while the mortality of the maize weevils was the lowest in the treatments with Asorbio®. The use of natural zeolites as a protectant for stored products was shown to be effective in our research, although additional surveys should be conducted.
•Higher mortality was detected in treatments, where we have used natural zeolites.•Exposure time, R.h. and temperature, have and important impact on efficacy of zeolites.•SiO2 content was significantly higher in natural, in comparison to synthetic zeolites.•Zeolites, which have form of clinoptilolite have higher efficacy than zeolite, formated as 4A.•Treatments with zeolites proved to have lower general mortality, in comparison to other inert dusts (wood ash, ...).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP