The evolution of resistance to insecticides poses a significant threat to pest management programs. Understanding the molecular mechanisms underlying insecticide resistance is essential to design sustainable pest control and resistance management programs. The fall armyworm, Spodoptera frugiperda, is an important insect pest of many crops and has a remarkable ability to evolve resistance to insecticides.
View Article and Find Full Text PDFBackground: The corn leafhopper, Dalbulus maidis, is an important pest in Brazil. While chemical control has traditionally been the cornerstone for managing this pest, field control failures have been reported for some insecticides. To understand if these failures are due to resistance, we evaluated the susceptibility of 11 field-collected populations of D.
View Article and Find Full Text PDFGenome-wide long non-coding RNAs (lncRNAs) in low, moderate, and high pyrethroid insecticide-resistant and -susceptible strains of were identified in this study. Using 45 illumina-based RNA-sequencing datasets, 8394 lncRNAs were identified. In addition, a sublethal dose of deltamethrin was administered to a Korean-resistant strain (Kor-T).
View Article and Find Full Text PDFBackground: Laboratory-selected resistant strains of Euschistus heros to thiamethoxam (NEO) and lambda-cyhalothrin (PYR) were recently reported in Brazil. However, the mechanisms conferring resistance to these insecticides in E. heros remain unresolved.
View Article and Find Full Text PDFSusceptibility monitoring to insecticides is a key component to implementing insecticide resistance management (IRM) programs. In this research, the susceptibility to teflubenzuron in (J.E Smith) was monitored in more than 200 field-collected populations from major corn-growing regions of Brazil, from 2004 to 2020.
View Article and Find Full Text PDFPest Manag Sci
June 2023
Background: Spodoptera frugiperda (J. E. Smith) is a widespread agricultural pest with several records of resistance to different insecticides and Bt proteins, including the neurotoxic insecticides chlorpyrifos (organophosphate) and lambda-cyhalothrin (pyrethroid).
View Article and Find Full Text PDFInsect Biochem Mol Biol
January 2023
The Neotropical brown stink bug, Euschistus heros, is a major pest of soybean in South America. The importance of E. heros as a pest has grown significantly in recent times due to increases in its abundance and range, and the evolution of insecticide resistance.
View Article and Find Full Text PDFFitness costs associated with insect resistance to insecticides can be exploited to implement resistance management programs. However, most of these studies are restricted to evaluating biological traits on artificial diets. Here, we investigated the fitness cost associated with chlorantraniliprole in Spodoptera frugiperda (J.
View Article and Find Full Text PDFFall armyworm (FAW), , is an important lepidopteran pest in the Americas, and recently invaded the Eastern Hemisphere. In Brazil, FAW is considered the most destructive pest of corn and cotton. FAW has evolved resistance to many insecticides and (Bt) proteins.
View Article and Find Full Text PDFThe interspecific variation in susceptibility to insecticides by lepidopteran species of soybean [Glycine max L. (Merr.)], cotton (Gossypium hirsutum L.
View Article and Find Full Text PDFBackground: Spodoptera frugiperda (J.E. Smith) is a difficult pest to manage mainly because of its resistance to insecticides and Bt proteins.
View Article and Find Full Text PDFWidespread adoption of MON 87701 × MON 89788 soybean, expressing Cry1Ac Bt protein and glyphosate tolerance, has been observed in Brazil. A proactive program was implemented to phenotypically and genotypically monitor Cry1Ac resistance in Chrysodeixis includens (Walker). Recent cases of unexpected injury in MON 87701 × MON 89788 soybean were investigated and a large-scale sampling of larvae on commercial soybean fields was performed to assess the efficacy of this technology and the distribution of lepidopteran pests in Brazil.
View Article and Find Full Text PDFThe novel ingestion bioassay method was developed for detecting and monitoring resistance of by encapsulating an artificial liquid diet using Parafilm. This methodology was compared with the tarsal contact (vial test) and topical application methods for thiamethoxam, imidacloprid, and lambda-cyhalothrin. The best bioassay method for the neonicotinoid insecticides thiamethoxam and imidacloprid was ingestion.
View Article and Find Full Text PDFThe soybean technology MON 87701 × MON 89788, expressing Cry1Ac and conferring tolerance to glyphosate, has been widely adopted in Brazil since 2013. However, pest shifts or resistance evolution could reduce the benefits of this technology. To assess Cry1Ac soybean performance and understand the composition of lepidopteran pest species attacking soybeans, we implemented large-scale sampling of larvae on commercial soybean fields during the 2019 and 2020 crop seasons to compare with data collected prior to the introduction of Cry1Ac soybeans.
View Article and Find Full Text PDFBackground: Fall armyworm, Spodoptera frugiperda (J. E. Smith), is a relevant global pest due to severe damage caused on agricultural crops and its capacity to evolve resistance to insecticides.
View Article and Find Full Text PDFCompetition behavior involving agricultural pest species has long been viewed as a powerful selective force that drives ecological and phenotypic diversity. In this context, a Game Theory-based approach may be useful to describe the decision-making dilemma of a competitor with impacts to guarantee its superiority in terms of ecological dominance or sharing of the food resource with its competitor. In an attempt to elucidate the consequences of competitive dynamics for the ecological dominance of these species in refuge areas of Bt cotton, we conducted a study that was divided into two parts.
View Article and Find Full Text PDFBackground: Brevipalpus yothersi mite is the main vector of Citrus leprosis virus (CiLV), the causal agent of citrus leprosis disease. The acaricide spirodiclofen has been widely used to control this mite. However, failures in control using spirodiclofen have been frequently reported by citrus growers.
View Article and Find Full Text PDFSpodoptera frugiperda (J.E. Smith) is one of the key cross-crop pests in Brazilian agroecosystems.
View Article and Find Full Text PDFBackground: 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA), the main benzoxazinoid found in corn, elicits variable larval responses from different pest moths. For the widespread and highly polyphagous Spodoptera frugiperda (Lepidoptera: Noctuidae), the fall-armyworm (FAW), DIMBOA acts as a feeding stimulant and improves larval growth at low concentrations. The FAW present two host plant-related strains, corn and rice strains, related to host preference on corn and other Graminae or rice.
View Article and Find Full Text PDFSpodoptera frugiperda is one of the main pests of maize and cotton in Brazil and has increased its occurrence on soybean. Field-evolved resistance of this species to Cry1 Bacillus thuringiensis (Bt) proteins expressed in maize has been characterized in Brazil, Argentina, Puerto Rico and southeastern U.S.
View Article and Find Full Text PDFPest Manag Sci
December 2020
Background: Spodoptera eridania (Stoll), S. cosmioides (Walker) and S. albula (Walker) (Lepidoptera: Noctuidae) are considered secondary pests of soybean in South America.
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