Akademik Veri Yönetim Sistemi
ZEITSCHRIFT FUR PFLANZENKRANKHEITEN UND PFLANZENSCHUTZ-JOURNAL OF PLANT DISEASES AND PROTECTION, cilt.110, sa.4, ss.394-400, 2003 (SCI-Expanded)
Repellents have the potential to prevent insect infestations in stored product environments through disrupting host-food finding by insects. The scale and duration of this disruptive activity depends on the concentration of the active agent in air and on its stability. In order to determine their repellency and stability as repellents against Tribolium confusum du Val adults, the activity of eight essential oil constituents listed below was tested 5 times within a period of 8 weeks at varying concentrations at the beginning, at the end of 1(st), 2(nd), 4(th) and 8(th) week. The initial percent repellency at a concentration of 23.1 mg/l air was as follows: anethole 82.4, carvacrol 67.5, 1,8-cineole 56.6, p-cymene 31.8, menthol 48.1, gamma-terpinene 39.8, terpinen-4-ol 39.0, and thymol 67-7. Although the repellent activity was concentration dependent, a disproportionate increase in repellency was attained by increasing concentrations, e. g., an eightfold increase produced only up to twofold increase in initial repellency of the constituents assayed. For all constituents tested, the repellent activity gradually decreased with increasing time. A decrease of 31-53% in initial repellency was recorded after 8 weeks at the highest concentrations of the constituents. However, decreases in initial activity became significant only after 8 weeks for anethole, 1,8-cineole and terpinen-4-ol or after 4 weeks for carvacrol and thymol. Anethole, carvacrol, 1,8-cineole and thymol were identified as the most promising repellents in that they showed the highest activity and stability among the eight essential oil constituents tested.