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U sažetku se opisuje laboratorijsko testiranje insekticidne učinkovitosti dijatomejskih zemalja (DZ) SilicoSec® i Celatom Mn-51® u suzbijanju žitnog kukuljičara Rhyzopertha dominica (Fab.) na pšenici s tri doze (250, 500 i 750 ppm) pri dvijema ekspozicijama (7 i 14 dana). Cilj rada je bio utvrditi insekticidnu učinkovitost testiranih DZ na žitnog kukuljičara te utvrditi optimalnu dozu. Pšenica (100 g) vlage 13, 5 % zaprašena je dijatomejskom zemljom (svaka DZ pojedinačno) u staklenkama volumena 200 ml, nakon čega je introducirano 20 jedinki žitnog kukuljičara različitog spola po tretmanu, starosti 7-21 dan. Svi tretmanu su postavljeni kroz četiri ponavljanja. Najviši mortalitet (82, 5 %) postignut je u tretmanu sa SilicoSec® pri dozi od 750 ppm nakon 14. dana ekspozicije. Statistički značajno viši mortalitet u odnosu na kontrolni tretman postignut pri ekspoziciji od 7 dana pri dozi od 500 ppm za obje dijatomejske zemlje. Produljenjem ekspozicije i povećanjem doze zabilježen je statistički značajno viši mortalitet. Navedeni rezultati ukazuju na visoku učinkovitost istraživanih DZ u suzbijanju žitnog kukuljičara na pšenici. Potrebna su daljnja istraživanja utjecaja navedenih DZ na razvoj potomstva žitnog kukuljičara.

Provedeno je istraživanje insekticidnog utjecaja dijatomejske zemlje, prašiva i ekstrakta carske paulovnije na žitnog kukuljičara. Primjenjeni su u tretmanima prašiva lista carske paulovnije, dijatomejska zemlja Celatom Mn-51® i SilicoSec®, te ekstrakti u različitim dozama nakon 7. i 14. dana ekspozicije. Od ekstrakata je korišten: vodeni ekstrakt carske paulovnije; kombinacija vodenog i alkoholnog ekstrakta carske paulovnije pri omjeru 1:1; te alkoholni ekstrakt (2-propanol) carske paulovnije. Insekticidna učinkovitost je ovisila o dozi i ekspoziciji. Najlošije se pokazalo prašivo carske paulovnije koje nakon 7. dana ekspozicije nije postiglo mortalitet. Dijatomejska zemlja (DZ) se pokazala najvišu insekticidnu učinkovitost. Povećanjem doze se i mortalitet povećavao te je najviša doza od 750 mg kg-1 postigla najviši mortalitet. DZ SilicoSec® je postigla viši mortalitet u odnosu na Celatom MN-51®. Od ekstrakata lista carske paulovnije najbolje je djelovao ekstrakt 3 (alkoholni ekstrakt), zatim kombinacija alkoholnog i vodenog ekstrakta carske paulovnije (ekstrakt 2), dok je najniži mortalitet postigao vodeni ekstrakt (ekstrakt 1) carske paulovnije., This research was conducted with the aim to test the insecticidal efficacy of diatomaceous earth, powder and extract of empress tree against lesser grain borer. Treatments with leaf powder of empress tree, diatomaceous earths Celatom Mn-51® and SilicoSec®, as well as extracts in different doses were applied in two different exposures (7 and 14 days). The following extracts were used: aqueous extract; combination of aqueous and alcoholic extract in 1:1 ratio; and alcoholic extract (2-propanol) of the empress tree. The insecticidal influence depended on the dose and exposure. The least effective was the powder of empress tree which on the seventh day of exposure has not achieved any mortality. Diatomaceous earth proved to have the highest insecticidal properties. As the doses were raised the mortality rate was higer. The highest dose (750 mg kg-1) achieved the highest mortality. Diatomaceous earth SilicoSec® achieved a higher mortality rate than Celatom Mn-51®. The most effective extract has proved to be extract 3 (alcoholic extract), followed by the combination of alcoholic and aqueous extract of (extract 2), while the lowest mortality rate was achieved by the aqueous extract (extract 1) of empress tree.

Prilikom skladištenja pšenice najvaţnije je utvrditi optimalne uvjete za trajnije i kvalitetnije skladištenje. Jedna od najĉešćih mjera zaštite uskladištenih proizvoda od skladišnih kukaca je primjena kemijskih preparata, pesticida. Obzirom na brojne neţeljene posljedice dugoroĉne i prekomjerne primjene sintetiĉkih pesticida, velika je potreba iznalaţenja novih nepesticidnih mjera koje bi bile manje štetne za okoliš i ljudsko zdravlje, a istovremeno jednako ili više uĉinkovite u odnosu na sintetiĉke pesticide. Cilj ovoga rada je utvrditi insekticidno djelovanje dijatomejske zemlje SilicoSec® i formulacije na bazi dijatomejske zemlje i biljnih komponenti na tri vrste skladišnih štetnika u laboratorijskim uvjetima. U istraţivanju su korišteni odrasli oblici ţitnog kukuljiĉara R. dominica, riţinog ţiška S. oryzae i kestenjastog brašnara T. castaneum. Korištena je sjemenska pšenica sorte Vulkan te je testirano inertno prašivo na bazi dijatomejske zemlje, SilicoSec® i formulacija dobivena mješavinom DZ SilicoSec® i biljnih komponenti (oznaĉena nazivom F Silico). Oba prašiva su testirana u 4 doze (300, 400, 500 i 600 ppm). Insekticidna djelotvornost DZ SilicoSec® i formulacije F Silico procijenjena je mortalitetom odraslih jedinki test kukaca nakon 7 i 14 dana, te utjecajem na razvoj potomstva F1 generacije. Rezultati djelovanja DZ SilicoSec® i formulacije F Silico na testirane kukce pokazali su razliĉito insekticidno djelovanje ovisno o apliciranoj dozi i ekspoziciji. MeĊu testiranim vrstama skladišnih štetnika izrazito osjetljive na testirana prašiva su se pokazale vrste S. oryzae i T. castaneum, dok je vrsta R. dominica bila nešto otpornija. Dobiveni rezultati ukazuju da se prirodna prašiva, DZ SilicoSec® i dobivena formulacija F Silico, mogu uspješno koristiti za ĉuvanje sjemenske pšenice od zaraze glavnih skladišnih štetnika; S. oryzae, T castaneum i R. dominica., During the storing of wheat the most importatnt thing is to determine optimal conditions for a longer and better quality of storing. One of the most common measures to protect stored products from insects is the use of chemical pesticides. Considering numerous unwanted consequences, long-term and excessive applications of synthetic pesticides, there is a great urge to find new non pesticides measures that would be less harmful to the environment and human health, but at the same time being equaly or more effective against synthetic pesticides. The objective of this research is to determine the insecticidal activity of diatomaceous earth SilicoSec® and formulation based on diatomaceous soil and plant components on three species of pests in laboratory conditions. In research we used adult forms of R. dominica (lesser grain borer), S. oryzae (rice weevil) and T.castaneum (red flour beetle). The wheat that was used is the variety Vulkan, and an inert dust based on diatomaceous earth SilicoSec®, and a formulation obtained from a mixture of DZ Silicosec® and plant components (marked by name F Silico) were tested. Both of this dusts were tested in 4 doses (300, 400, 500 i 600 ppm). Insecticidal activity of DZ SilicoSec® and formulation of F Silico is estimated by mortality of adults after 7 and 14 days and influencing the development posterity of the F1 generation. Results of action of DZ SilicoSec® and formulation of the F Silico on tested pests show different insecticidal activity depending on the dosage and exposure. Among the tested species of storage pests, the most sensitive to the tested dust were T. castaneum and S. oryzae, while R. dominica was more resistant. The results indicate that the natural powder DE SIlicoSec® and the obtained formulation F Silico, can be successfully used for protection of wheat against the main storage pests: R. domenica, S. oryzae, and T. castaneum.

The insecticidal activity of two commercial formulations of diatomaceous earths (DEs) was evaluated in the laboratory against two major pests of stored grain: Rhyzopertha dominica (F.) (Coleoptera Bostrichidae) and Sitophilus oryzae (L.) (Coleoptera Curculionidae). The formulations Protector® and SilicoSec® were tested at two different doses (500 and 1000 ppm) against adults of the two species. Bioassays were carried out using 2-liter-glass jars containing common wheat (with a moisture content ranging from 10.5 to 11.7%, for R. dominica, and 10.7 to 13.4% for S. oryzae) mixed with the DEs, and maintained at 26.7 °C and 60% RH. The efficacy of the treatment was evaluated by recording adult mortality after 2, 7 and 14 days. Both formulations have shown an adulticidal effect, although the mortality was influenced by species, dosages and exposure time. Protector® showed a significant insecticidal activity against the lesser grain borer and the rice weevil already after two days of treatment. After 14 days the mean mortality was greater than 95% even at a dosage of 500 ppm for R. dominica, and greater than 87 and 92% at a dosage of 500 ppm and 1000 ppm respectively, for S. oryzae. SilicoSec® caused less mortality than Protector® after 2 days of exposure, especially for the S. oryzae. However, there was no difference between formulations after 7 or 14 days.