The toxicity of seven biorational insecticides [five insect growth regulators (Buprofezin, Fenoxycarb, Pyriproxyfen, Methoxyfenozide, and Tebufenozide) and two oil-extracts of neem and bitter gourd seeds] againstBemisia tabaciand their selectivity for its parasitoid,Encarsia formosawere evaluated in laboratory and field conditions for 2 years (2018–2019) in Pakistan. Toxicity results demonstrate that Pyriproxyfen, Buprofezin, and Fenoxycarb proved to be effective (80–91% mortality and 66.3–84.2% population-reduction) againstB. tabacifollowed by Methoxyfenozide, Tebufenozide (50–75% mortality and 47.8–52.4% population-reduction), and then oil-extracts of neem and bitter gourd (25–50% mortality and 36.5–39.8% population-reduction) in the laboratory [72 h post-application exposure interval (PAEI)] and field trails (168 h PAEI), respectively. All tested biorationals, except Methoxyfenozide [(slightly-harmful/Class-II), i.e., causing mortality of parasitoids between a range of 25–50%] and Tebufenozide [(moderately-harmful/Class-III), i.e., causing mortality of parasitoids between the ranges of 51–75%], proved harmless/Class-I biorationals at PAEI of 7-days in the field (parasitism-reduction < 25%) and 3-days in the lab (effect < 30%). In laboratory bioassays, exposure of parasitized-pseudopupae and adult-parasitoids to neem and bitter gourd oils demonstrated that these compounds proved harmless/Class-I biorationals (< 30% mortality). Alternatively, Pyriproxyfen, Buprofezin, Fenoxycarb, Methoxyfenozide, and Tebufenozide were slightly-harmful biorationals (30–79% mortality) against the respective stages ofE. formosa. We conclude that most of the tested biorationals proved harmless or slightly harmful toE. formosa, except tebufenozide after PAEI of 7-days (168 h) in the field and, therefore, may be used strategically in Integrated Pest Management (IPM) ofB. tabaci.

Background: The peach fruit fly, Bactrocera zonata (Saunders) (Diptera: Tephritidae), is a serious polyphagous pest of fruits and vegetables. Chemical management of B. zonata in fruits results in toxic residues that have adverse health effects on consumers resulting in increased demand for eco-friendly approaches. Laboratory bioassay was conducted to determine the pathogenicity of fungal and bacterial biopesticides against B. zonata. Results: The pathogenicity of all tested bioinsecticides revealed that the maximum concentration (1 × 10⁸ CFU ml⁻¹) of Metarhizium anisopliae, Beauveria bassiana, Lecanicillium lecanii and Bacillus thuringiensis caused 95.8–100%, 95.9–97.9%, 32.7–39.6%, and 20.0–22.4% mortality in B. zonata, respectively at 7 d post-application interval (PAI) as compared to mortality demonstrated by the same concentration at 5 d PAI. All tested microbial insecticides induced statistically similar mortality in both male and female B. zonata at each concentration for the same PAI. Correlation coefficient (r) values reveal that concentrations of each microbial insecticide had a high positive correlation with mortalities of male and female B. zonata. Regression parameters reveal that concentrations of tested microbial insecticides had significant linear relationship with and explained significant variability in B. zonata mortality (P < 0.05). Results also revealed that M. anisopliae was proved more pathogenic to males and females of B. zonata demonstrating the least LC₅₀ values (5.48 × 10³, and 6.17 × 10³ CFU ml⁻¹, respectively) 7 d post-application intervals, followed by B. bassiana which explained LC₅₀ value of 1.14 × 10⁴ CFU and 1.15 × 10⁵ CFU ml⁻¹ for B. zonata males and females, respectively, at the same period of application, but less than that of L. lecanii (2.77 × 10⁹ and 1.43 × 10⁹ CFU ml⁻¹) and then B. thuringiensis (3.40 × 10¹⁰ and 1.39 × 10¹⁰ CFU ml⁻¹) for the males and females, respectively, at 7 d PAIs. Conclusion: Metarhizium anisopliae incorporated adult diet was proved more effective against B. zonata, followed by B. bassiana, L. lecanii, and B. thuringiensis. Hence, M. anisopliae can be recommended for incorporating in bait-traps to develop attract-and-kill technology for B. zonata.