14332

12959

كارشناسي ارشد

گياهپزشكي

اصفهان : دانشگاه صنعتي اصفهان

1397

سيزده، ۶۶ص.: مصور، جدول، نمودار

جهانگير خواجه علي

امير مساح

نفيسه پورجواد، رحيم مهرابي

1397/11/24

كتابنامه

كشاورزي

مهندسي كشاورزي

1397/11/27

ID12959

Evaluation of resistance to abamectin and cypermethrin in the populations of Tuta absoluta collected from Isfahan province Marziyeh Azizi marziyeh azizi@ag iut ac ir January 13 2019 Department of Plant Protection Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor Dr Jahangir Khajehali J Khajeali@cc iut ac irAbstractThe tomato leaf minor Tuta absoluta Meyrick Lepidoptera Gelechiidae is one of the most importantpests of tomato in world and Iran Due to significant resistance of this pest against insecticides principlesof resistance management must be considered in pesticides application In this study resistance of differentpopulations of the tomato leaf minor from Isfahan province was evaluated against abamectin andcypermethrin The median lethal concentration LC50 of different populations were measured by bioassaysusing a leaf dip method The LC50 of abamectin in the reference population of Isfahan University ofTechnology IUT was estimated as 5 67 mg a i L while the population of Shahre e Abrisham1 showed a25 fold resistance with on LC50 value of 143 18 mg a i L Other treated populations showed also 2 to 20 fold resistance to abamectin Pre treatment of different populations with DEM synergist on inhibitor ofglutathione s transferases GSTs increased 2 7 to 5 9 fold of the toxicity of abamectin GST activity wassignificantly different between resistant and reference populations TPP on inhibitor of esterases ESTs increased abamctin toxicity in the populations as much as 2 5 to 3 7 fold The activity of ESTs in thesepopulations was also significantly different Furthermore inhibiting of cytochrome P450 monooxygenasesby PBO increased abamectin toxicity about 3 fold in the population of Shahre e Abrisham1 It seems thatGSTs and ESTs play a more important role in the resistance development against abamectin in the studiedpopulations Also the zymograms for ESTs have proved their role in abamectin resistance Againstcypermethrin a tested populations showed an LC95 4600 mg a i L while recommended dose of thisinsecticide is about 30 mg a i L PBO pre treatment reduced LC50 of cypermethrin more than TPP andDEM The synergistic ratios of PBO for the reference population of IUT and Mourche Khort populationwere 2 16 and 3 51 respectively The activities of cytochrome P450 monooxygenases in Falavarjan andMourche khort populations were evaluated 2 and 1 26 times higher than that of IUT population respectively DEM synergist increased cypermethrin toxicity in the resistant population of Kondelan 3 67 fold while in IUT population 2 fold synergistic ratio was observed Also enhanced activity of GSTs inresistant populations was possibly associated with resistance to cypermethrin In addition increasedcypermethrin toxicity after inhibiting the activity of ESTs by TPP was not significant between testedpopulations Evaluating the activity of ESTs in the reference and resistant populations did not show anysignificant difference Therefore it could be concluded that cytochrome P450 monooxygenase and GSTenzymes play a minor role in resistance of cypermethrin but the main resistance mechanism possibly wasassociated with mutations in the pest sodium channel gene High levels of resistance to abamectin andcypermethrin in the collected populations from Isfahan province shows the importance of insecticideresistance management based on alternative use of insecticides with different mode of action or chemicalgroup Keywords Enzyme activity Synergist Insecticide resistance management 67

جهانگير خواجه علي

امير مساح

نفيسه پورجواد، رحيم مهرابي