Sublethal effects of diflovidazin on life table parameters of two-spotted spider mite Tetranychus urticae (Acari: Tetranychidae)

ABSTRACT

The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae) is a serious pest of many agricultural crops. Using chemical pesticides is one of the main methods for its management. In this study, sublethal effects of diflovidazin including LC₅, LC₁₀, LC₂₀, and distilled water were evaluated on biological parameters (such as r, λ, gross reproductive rate, R₀, and T) of T. urticae. The experiments were done under laboratory condition at 25 ± 2°C, 60 ± 5% relative humidity (RH), and a photoperiod of 16:8 (L: D) hours. The crude data were analysed based on age-stage, two-sex life table analysis. The results indicated significant reduction in female’s duration of maturation, oviposition period, and total fecundity by increasing examined dose. The highest and lowest values of the net reproductive rate (R₀) were obtained 48.88 and 31.14 offspring/individual in control and LC₂₀, respectively. The maximum value of intrinsic rate of increase (r) was 0.234 day⁻¹ that obtained in control treatment, while the minimum value was 0.216 day⁻¹ obtained in LC₂₀ concentration. Finite rate of increase (λ) had not significantly descended with concentration enhancing from LC₅ to LC₂₀ compared with the control. The results demonstrated that diflovidazin could be incorporated in integrated pest management programmes of T. urticae.

KEYWORDS:

• Acari
• sublethal effects
• Flumite
• Tetranychus urticae
• life table

Acknowledgement

We greatly appreciate the University of Tehran’s support on this project.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the University of Tehran.