اثرات زیرکشنده فرمولاسیون‏های نانوکپسول و مایع امولسیون‏شونده اسانس‏های نعناع‏فلفلی و رزماری بر مینوز برگ گوجه‏فرنگی Tuta absoluta

Tomato is one of the most important agricultural crops and the second major vegetable crop worldwide after potato. Tomato leaf miner, Tuta absoluta; Lepidoptera: Gelechiidae, is one of the important insect pests of this product, which poses a serious threat to tomato production across the world. Control of this pest is mostly dependent on the application of chemical insecticides ( Organophosphates, Pyrethroids, Oxadiazins, Spinosyns, Avermectins, Diamides). Following commercial use of plant essential oils (EOs) in pest control, their slow-release formulations have been developed in order to increase their effectiveness and solve their instability problem. In the present study, at first, the lethal activity of peppermint (Mentha piperita L.) and rosemary (Rosmarinus officinalis L.) EOs as emulsifiable concentrates (EC) and nano-capsules (NC) on the tomato leaf miner was determined by the leaf-dipping method. Mortality of different concentrations (1, 5, 10, 20 and 40 percent) recorded at 24, 48 and 72 hours after treatment. The 40 percent concentration caused severe phytotoxicity. The corrected mortality of lower tested doses was less than 30 percent for both formulations. Thus, the concentration of 10% (LC15) of nano-formulated EOs was selected to study their sub-lethal effects. The demographic and biological parameters of the life table were calculated and compared with TwoSex-MSChart (chi) software. The results of the sub-lethal study showed a significant increase in the larval duration in both treatments compared to that of control. So that the longest larval duration was observed in nano-capsule formulation of rosemary (9.24 ± 0.15 day) and the lowest larval duration was observed in the control (7.78 ± 0.16 day). However, the nano-capsule formulations of EOs had no effect on the adult longevity, but peppermint nano-capsules significantly decreased the ovipositional period compared to that of control and rosemary nano-capsules. Fertility and survival rates were also significantly decreased in females treated with rosemary nano-capsules. Analysis of life table parameters showed a significant decrease in the intrinsic rate of increase (rm) and the finite rate of increase (λ) in treatment with rosemary nano-capsules. Net reproductive rate (R0) was significantly decreased in treatment with both EOs compared to the control. Also, the inhibitory effects of both EO formulations, EC and NC, were investigated on the female oviposition and results showed that the lowest average number of eggs observed in nano-capsules. The study of the phytotoxicity of formulations on tomato plants showed an increased toxicity in nano-capsules. Peppermint nano-capsules showed highest phytotoxicity. In general, rosemary essential oil has the ability to use in integrated pest management programs because of a reasonable reduction in the pest developmental parameters, higher inhibition effect on adult female oviposition and less phytotoxicity.