Investigation of resistance levels against synthetic pyrethroids in German and American cockroach populations in Antalya province

Cockroaches are mechanical vectors of many disease agents like bacteria, viruses, fungi, etc. Tons of insecticides are used every year to combat these insects. Wrong pest control methods and unconscious use of insecticides have caused resistance in cockroaches. In this thesis, resistance levels against some synthetic pyrethroid insecticides, deltamethrin, permethrin, alpha-cypermethrin and lambda-cyhalothrin, in the German (Blattella germanica L.) and American (Periplaneta americana L.) cockroaches collected from different localities of Antalya province were determined. Resistance tests were performed using the standard glass jar surface method recommended by World Health Organization (WHO). The second and third instar nymphs of the cockroaches were exposed to the test chemicals for one hour, and knock-down rates, LD50 values, resistance ratios and resistance levels were determined. According to the results obtained, the tested chemicals were very high toxic to the American cockroach, resulting in a mortality rate of ≥95% at recommended doses by WHO. The resistance ratios of all the populations were found between 1 and 2, that's why all populations have no resistance, very low resistance or low resistance in terms of resistance status. In German cockroaches, the toxic effect was very low (0 to 80% mortality) in the field-collected populations, although the WHO recommended doses of the tested chemicals were generally assessed as highly toxic (≥96,7% mortality) on the sensitive population. When evaluated according to the resistance ratios, high resistance was observed at all the populations except permethrin and lambda-cyhalothrin active substances in the Güllük population. As a result, it is thought that unconscious use of chemical insecticides in the past and also the long-lasting use of synthetic pyrethroids may lead to high resistance in German cockroaches. Currently, no resistance has been found in American cockroaches against the tested synthetic pyrethroid active substances. In order to prevent resistance to active substances, the integrated pest management approach should be prioritized and chemical control should be kept at the lowest level. KEYWORDS: German cockroach (Blattella germanica L.), American cockroach (Periplaneta americana L.), Resistance, Synthetic pyrethroid