20.500.12556/RUL-182567 Dejavniki insekticidnega delovanja pripravkov iz invazivnih tujerodnih rastlinskih vrst na izbrane skladiščne hrošče Factors of insecticidal activity of invasive alien plant species formulations on selected storage beetles Hrošče iz rodu Sitophilus uvrščamo med najpomembnejše škodljivce skladiščenega žita, kar potrjuje dejstvo, da se kar tri vrste iz tega rodu uvrščajo med 10 najbolj preučenih škodljivcev skladiščenih proizvodov. V naših raziskavah smo preučevali kontaktno delovanje prahov na hrošče vrste S. oryzae, repelentni učinek na hrošče vrste S. zeamais, za zatiranje hroščev vrste S. granarius pa smo uporabili rastlinske vodne izvlečke. Zaradi vse večje ozaveščenosti o nevarnostih sintetičnih insekticidov na okolje, imajo rastlinski insekticidi, zaradi njihove okoljske prijaznosti obetavno prihodnost, ker lahko delujejo kot insketicidna ali repelentna sredstva na žuželke. Ravno zato smo se odločili preučiti insekticidno delovanje biorazgradljivih rastlinskih prahov in vodnih izvlečkov iz sledečih rastlinskih vrst: Solidago canadensis, Solidago gigantea, Rhus typhina, Amorpha fruticosa in Ailanthus altissima. Gre za invazivne tujerodne vrste, za katere je značilno, da njihova zastopanost ogroža domače avtohtone vrste v ekosistemih in jih je potrebno odstraniti iz okolja. Odločili smo se preveriti, ali so navedene vrste rastlin lahko uporabne za zatiranje škodljivcev iz rodu Sitophilus. V raziskavi smo uporabili tudi inertne prahove, in sicer kremenov pesek, zeolit, lesni pepel navadne smreke in tržni pripravek SilicoSec®. V obeh raziskavah, kjer smo preučevali kontaktno delovanje prahov, se je izkazalo, da so inertni prahovi bolj insekticidno učinkoviti, saj je bil pripravek SilicoSec® najučinkovitejši pri zatiranju riževega žužka, kjer je bila 100 % smrtnost hroščev pri 20 in 25 °C za 55 % opažena že po 8 dneh pri 20 °C in 75 % RH pa po 14 dneh. V raziskavi, kjer smo uporabili hrošče vrste S. zeamais, smo potrdili rezultate naše prve raziskave, da so prahovi tujerodnih invazivnih vrst insekticidno neučinkoviti, tudi tokrat pa je bil najučinkovitejši pripravek SilicoSec®, saj je bila stopnja preživetja po 14- dnevnem tretiranju majša od 15 %. V vseh treh poskusih je imela temperatura velik pomen pri insekticidnem delovanju prahov. Ugotovili smo, da je bila največja smrtnost hroščev ugotovljena pri 10 °C, medtem ko je bila pri 25 °C najmanjša. Potrdili smo, da je vrsta S. granarius bolj odporna na nizke temperature kot vrsti S. oryzae ali S. zeamais in posledično je pričakovano boljši nadzor pri nižjih temperaturah. Vodni ekstrakti invazivnih rastlin so se izkazali za neučinkovite, največji insekticidni učinek pa je bil zaznan samo po 24 urah, nato pa je sledil padec učinkovitosti. Pri preučevanju številčnosti potomstva so prahovi invazivnih rastlinskih vrst povzročili zmanjšanje števila potomcev vrste S. granarius za približno 30 % v primerjavi s kontrolo, kar ni zanemarljivo, vendar pa je to še vedno značilno nižja učinkovitost, kot so jo imeli pripraveki SilicoSec®, zeolit in lesni pepel smreke, kjer potomstva praktično ni bilo. Beetles of the genus Sitophilus are among the most important pests of stored grain worldwide, as confirmed by the fact that three species of this genus are among the 10 most studied pests of stored products. In our research, we tested the contact action of powders on S. oryzae beetles, the repellent effect on S. zeamais beetles, and for S. granarius beetles, we used plant aqueous extracts. Due to the increasing awareness of the dangers of synthetic insecticides to the environment, plant biopesticides, due to their environmentally friendly nature, have a promising future, as they can act as insecticides or repellents for insects. For this reason, we decided to prepare biodegradable plant powders and aqueous extracts from the following plant species: Solidago canadensis, Solidago gigantea, Rhus typhina, Amorpha fruticosa and Ailanthus altissima. These are invasive alien species, whose presence threatens native indigenous species in the ecosystem and requires their removal from the environment. Since they are scheduled for incineration, we decided to investigate whether they can be useful for controlling pests from the Situphilus genus. In order to assess the effectiveness of plant powders, we also used inert powders: quartz, zeolite, SilicoSec® and spruce wood ash. In both studies, where we had contact action, it turned out that inert powders are more insecticidally effective, as SilicoSec® was the most effective in controlling S. oryzae, where 100% mortality was observed already 8 days after treatment at 20 and 25 °C for 55 % RH, and at 20 °C and 75 % RH after 14 days. In the study using S. zeamais, we confirmed the results of our first study that dusts of non-native invasive species are insecticidally ineffective, and again SilicoSec® was the most effective, as the survival rate fell below 15 % after 14 days of treatment. In all three experiments, temperature played an important insecticidal role. The results showed that the highest mortality was observed at 10 °C, while the lowest was at 25 °C. We confirmed that S. granarius is more cold-resistant than S. oryzae or S. zeamais and consequently better control is expected at lower temperatures. Aqueous extracts proved ineffective, as a greater effect was detected only immediately after 24 hours, followed by a drop in effectiveness, as aqueous extracts dry out during this period and thus lose their volatile properties. In the progeny test, plant powders of invasive plant species showed a reduction in the number of S. granarius progeny by approximately 30 % compared to the control, which is not negligible, but this is still not even close to the effectiveness shown by SilicoSec®, zeolite and wood ash, where there were practically no progeny at all. zatiranje skladiščnih škodljivcev invazivne tujerodne rastlinske vrste Sitophilus zeamais Sitophilus granarius Sitophilus oryzae insekticidi učinkovitost repelentnost nekemično zatiranje škodljivcev Storage pest control Invasive alien plant species Sitophilus zeamais Sitophilus granarius Sitophilus oryzae insecticides effectiveness repellency non-chemical pest control true false false Slovenski jezik Angleški jezik Doktorsko delo/naloga 2026-05-17 07:15:47 2026-05-17 07:16:04 2026-05-18 15:33:59 0000-00-00 00:00:00 2026 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 279755 278547971 57437.pdf 57437.pdf 1 56FA112688B7C1EAAA6612A235FF105C 7b094b459e970b590bcfcb6ec3ca67e0a133137f2d71db1702c82a4f1c112619 313f2b8e-51af-11f1-b0ab-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=233942 Biotehniška fakulteta 0 0 0