Acute and Chronic Toxicity of Indoxacarb in Two Populations of Plutella xylostella (Lepidoptera: Plutellidae)

Abstract

The diamondback moth, Plutella xylostella (Linnaeus, 1758), is one of the main pests of brassicas, and various insecticides, such as indoxacarb, are used to control it. However, frequent insecticide applications favor the selection of resistant individuals. Thus, the residual and sublethal effects of indoxacarb in two populations of P. xylostella, one collected in the field (FP) and one from the laboratory (LP), were evaluated and compared. The objective of this research was to investigate the toxicity of indoxacarb at residual and sublethal levels in a field population of P. xylostella from Brazil and a population from the laboratory. Leaf-dip bioassays showed high toxicity, with LC50 values after 48 h of 3.7 and 6.9 mg/liter for the LP and FP, respectively. Sublethal effects were indicated by significant reduction in the survival of larvae, pupae, and offspring. There was an increase in foliar consumption and a decrease in adult survival in the LP, and a decrease in fecundity in the FP. For the LP and FP population, the mean values for R0, rm, and λ for the control treatment were significantly higher than for the treatment groups (CL15 and CL25). Exposure of larvae to sublethal indoxacarb concentrations significantly reduced larval and pupal survival. Larval and pupal survival decreased as the indoxacarb concentration increased. Fecundity was significantly lower for the FP at LC15 (96.2 eggs per female) and LC25 (69.2 eggs per female) concentrations compared with the other treatments.

Entomopathogenic Fungi-Mediated AgNPs: Synthesis and Insecticidal Effect against Plutella xylostella (Lepidoptera: Plutellidae)

“…The studies reporting the insect life cycle in the toxicity analyses provide knowledge about the total effect of a particular substance [ 48 ]. The larval viability is a parameter directly proportional to caterpillar mortality, thus these results can be correlated ( Figure 9 ).…”

Toxicity and Sublethal Effects of Diamide Insecticides on Key Non-Target Natural Predators, the Larvae of Coccinella septempunctata L. (Coleoptera: Coccinellidae)

“…Long-term toxic effects on aspects such as growth and development, reproduction, and offspring may occur in addition to acute toxicity. These effects could result in pesticide resistance, fewer offspring, decreased reduced effectiveness, and lower population levels of these natural enemies in agricultural ecosystems [ 27 ].…”

“…The risks of chemicals on environmental organisms (including predators, parasitoids, and aquatic algae) can be assessed by several environmentally relevant endpoints [ 28 ], which can be used to prove the margin of safety for pesticides on environment [ 27 , 29 ]. The LR 50 at different observation points was significantly different.…”

Integrated mass spectrometry imaging and metabolomics reveals sublethal effects of indoxacarb on the red fire ant Solenopsis invicta

“…Lemes et al . demonstrated that sublethal concentrations of indoxacarb affected the biological parameters of Plutella xylostella , including fecundity, longevity, and a decrease in adult emergence 24 . Additionally, indoxacarb has been widely used as bait due to the advantages of time‐/labor‐saving procedures and is suitable for large‐area control 25,26 .…”

“…23 Lemes et al demonstrated that sublethal concentrations of indoxacarb affected the biological parameters of Plutella xylostella, including fecundity, longevity, and a decrease in adult emergence. 24 Additionally, indoxacarb has been widely used as bait due to the advantages of time-/labor-saving procedures and is suitable for large-area control. 25,26 The use of insecticidal baits can be an effective method in the prevention and control of S. invicta, as it enables the distribution of toxicants throughout a colony.…”