UČINKOVITOST MIKROKAPSULIRANIH REPELENTOV NA OSNOVI EKSUDATA Psyadia punctulata IN ETERIČNIH OLJ DAPHNE

Vojko ŠKERLAVAJ¹_, Bojana BOH², Emil KNEZ³, Jacob OGWENO MIDIWO⁴

¹Kmetijski inštitut Slovenije, Oddelek za varstvo rastlin, SI-1001 Ljubljana, Slovenija
 ² Univerza v Ljubljani, Naravoslovnotehniška fakulteta, SI-1001 Ljubljana, Slovenija
³Aero d.d., SI-3000 Celje, Slovenija
⁴ University of Nairobi, Department of Chemistry

V prispevku so predstavljeni rezultati preizkušanja učinkovitosti mikrokapsuliranih repelentov, ki vsebujejo izločke listov rastline Psyadia punctulata oziroma odvračalni pripravek daphne. Aktivna učinkovina daphne (Dragoco, Avstrija) je zmes več kot dvajsetih naravnih in sintetičnih hlapnih spojin, ki učinkujejo kot vonjalni in okušalni repelent proti divjadi. Psiadia punctulata, rastlinska vrsta vzhodne Afrike, je znana po odvračalnem učinku na herbivorne živali tudi v času močne suše. Kot okušalno odvračalo je bil testiran izvleček te rastline, pridobljen z acetonsko ekstrakcijo smolnatega površinskega eksudata listov. Mikrokapsuliranje je bilo izpeljano po modificiranem postopku in situ polimerizacije aminoaldehidnih smol ob dodatku stiren-maleinanhidridnega modifikatorja. Pripravki so bili formulirani v obliko suspenzij s polivinilalkoholnimi in akrilatnimi vezivi. Učinkovitost odvračalnega delovanja proti srnam (Capreolus capreolus Linne) smo preizkušali v zimskem obdobju s pomočjo vab z enoletnimi jablanovimi poganjki, postavljenimi na površinah, posejanih z žitom. Spremljali smo obžiranje poganjkov v različnih časovnih presledkih. Rezultati testiranja so pokazali, da je mikrokapsuliranje v vseh primerih podaljšalo čas učinkovanja in učinkovitost odvračala v primerjavi s standardnim pripravkom na osnovi eteričnega olja daphne.

ABSTRACT

EFFICACY OF MICROENCAPSULATED REPELLENTS BASED ON Psyadia punctulata EXUDATE AND DAPHNE ESSENTIAL OILS

The contribution presents the results of testing the efficacy of microencapsulated repellents, based on Psyadia punctulata leaf exudate, and Daphne repellent. The active compound of Daphne (Dragoco, Austria) is a mixture of more than twenty natural and synthetic volatile compounds, contributing to smell- and taste-based repellent effects against deer. Psiadia punctulata, a plant species from Eastern Africa, is known to be avoided by browsing herbivores, even during severe drought. Its extract, obtained by acetone extraction of a resinous surface leaf exudate, was tested as a taste-based repellent. A modified in situ polymerization method of aminoaldehyde resins with styrene-maleic acid anhydride modifier was used for the microencapsulation. The product was mixed with polyvinyl alcohol and acrylate binders into a suspension formulation. The efficacy of the repellent on roe deer (Capreolus capreolus Linne) in winter was tested with baits, containing one-year-old apple branches, on agricultural surfaces sown with wheat. The damage caused by browsing was evaluated at different time intervals. The results of testing showed that all microencapsulated repellent formulations exhibited a prolonged activity and improved efficacy in comparison with the standard non-encapsulated Daphne repellent.