Functional response of Typhlodromus bagdasarjani and Phytoseiulus persimilis (Acari: Phytoseiidae) feeding on Tetranychus urticae (Acari: Tetranychidae) on rose

Rose is one of the most valued cut flowers and Tetranychus urticae Koch is one of its most important pests. Due to harmful effects of pesticides, biological control is one of the best methods in pest control. Typhlodromus bagdasarjani Wainstein & Arutunjan from family Phytoseiidae is a species with wide distribution in Iran. Phytoseiulus persimilis Athias-Henriot is an exotic and most commonly used species in greenhouses. Functional response is one of the important criteria for the effectiveness estimation in biological control programs. In this research, functional response of three-days old mated females to different densities to T. urticae eggs was studied on Rosa hybrida cv. Blarodje. Prey densities were 2, 4, 8, 15, 25, 35, 50 and 75 for females of P. persimilis and 2, 4, 8, 15, 25, 35, 50, 75, 100 and 120 for females of T. bagdasarjani. Based on logistic regression, functional response type III was determined for both predators. Also, handling time and b parameters for P. persimilis were estimated 0.5939±0.0058 hour and 0.0187±0.0020 and handling time parameter and b and d parameters for T. bagdasarjani were estimated 0.2409±0.0067 hour, 0.0033±0.0007 and 0.0637±0.0246, respectively. Functional responses of two predators were compared with each other. Handling time has significant differences in two Predators. Apparently, T. bagdasarjani ability in predation on T. urticae eggs is more than P. persimilis.