Effects of Different Aqueous Ozone Exposure Times and Usage Times on Mortality of Tetranychus urticae Koch on Capsicum annuum L.

Keivanloo, Ensieh; Sadeghi-Namaghi, Hussein; Haddad Khodaparast, Mohammad Hossein; Moravvej, Gholamhossein; Amiri-Jami, Alireza

doi:10.21608/eajbsa.2020.109404

Effects of Different Aqueous Ozone Exposure Times and Usage Times on Mortality of Tetranychus urticae Koch on Capsicum annuum L.

Document Type : Original Article

Authors

¹ Department of Plant Protection, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran

² Department of Plant protection, faculty of Agriculture, Ferdowsi University of Mashhad, Iran

³ Department of Food Science and Technology, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran

⁴ Plant Protection Research Department, Khorasan Razavi Agricultural and Natural Resources Research and Education Center, AREEO, Mashhad, Iran

10.21608/eajbsa.2020.109404

Abstract

Tetranychus urticae Koch, is a major pest of many plants including greenhouse and field crops in the world. The development of resistance in T. urticae populations to pesticides has motivated the search for alternative control methods to suppress the pest. The control of T. urticae by ozonated water on pepper (Capsicum annuum L.) was tested in greenhouse trials. Ozone at 43 g/m³concentration with a flow rate of 12.87 g/h ozone was applied as aqueous form at different times (8 am, 2 pm and 8 pm) and different ages of the plant (4, 8 and 12 weeks old) for three exposure times (5, 10 and 15 seconds). The results indicated that in all treatments, T. urticae was susceptible to 43 g/m³ozone concentration. In all cases, differences in mortality percentage of control and ozone treatments were significant, but differences in the mortality percentage among either time of application or duration of exposure time and ages of plant treatments were not significant. Also, no symptom of injury (chlorosis, necrosis, yellowing, or malformation) was observed for any of the pepper's leaves after aqueous ozone spraying. Based on these results, aqueous ozone can reduce the population density of T. urticae without any visible damage on the pepper leaves. However, more research needs to be done before ozonated water can be deployed commercially as a pesticide.

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