First Sprayable Double-Stranded RNA-Based Biopesticide Product Targets Proteasome Subunit Beta Type-5 in Colorado Potato Beetle (Leptinotarsa decemlineata)

Colorado potato beetle (CPB, Leptinotarsa decemlineata) is a major pest of potato and other solanaceous vegetables in the Northern Hemisphere. The insect feeds on leaves and can completely defoliate crops. Because of the repeated use of single insecticide classes without rotating active ingredients, many chemicals are no longer effective in controlling CPB. Ledprona is a sprayable double-stranded RNA biopesticide with a new mode of action that triggers the RNA interference pathway. Laboratory assays with second instar larvae fed Ledprona showed a dose–response where 25×10−6g/L of dsPSMB5 caused 90% mortality after 6days of initial exposure. We also showed that exposure to Ledprona for 6h caused larval mortality and decreased target messenger RNA (mRNA) expression. Decrease in PSMB5 protein levels was observed after 48h of larval exposure to Ledprona. Both PSMB5 mRNA and protein levels did not recover over time. Ledprona efficacy was demonstrated in a whole plant greenhouse trial and performed similarly to spinosad. Ledprona, currently pending registration at EPA, represents a new biopesticide class integrated pest management and insecticide resistance management programs directed against CPB.

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Conjugated linoleic acid as a novel insecticide targeting the agricultural pest Leptinotarsa decemlineata

10.1101/715011 ◽

2019 ◽

Author(s):

Justin Clements ◽

Russell L. Groves ◽

JoAnn Cava ◽

Caroline Barry ◽

Scott Chapman ◽

...

Keyword(s):

Linoleic Acid ◽

Conjugated Linoleic Acid ◽

Colorado Potato Beetle ◽

Leptinotarsa Decemlineata ◽

Larval Mortality ◽

Larval Growth ◽

The United States ◽

Feeding Preference ◽

Agricultural Pest ◽

Potato Beetle

AbstractThe Colorado Potato Beetle, Leptinotarsa decemlineata, is a major agricultural pest of solanaceous crops in the United States. Historically, a multitude of insecticides have been used to control problematic populations. Due to increasing resistance to insecticides, novel compounds and methodologies are warranted for the control of beetle populations. Mixed-isomer conjugated linoleic acid has been studied in-depth for its beneficial properties to mammalian systems. At the same time, studies have demonstrated that conjugated linoleic acid can manipulate fatty acid composition in non-mammalian systems, resulting in embryo mortality. Consequently, experiments were conducted to assess the effects of foliar-applied conjugated linoleic acid on larval growth, embryogenesis, and feeding preference in Colorado potato beetle. Both maternal and deterrent effects of dietary conjugated linoleic acid were assessed. Conjugated linoleic acid demonstrated desirable insecticidal properties, including increased larval mortality, slowed larval development, antifeedant effects, and decreased egg viability after maternal ingestion.

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Modern Techniques in Colorado Potato Beetle (Leptinotarsa decemlineata Say) Control and Resistance Management: History Review and Future Perspectives

Insects ◽

10.3390/insects11090581 ◽

2020 ◽

Vol 11 (9) ◽

pp. 581 ◽

Cited By ~ 2

Author(s):

Martina Kadoić Balaško ◽

Katarina M. Mikac ◽

Renata Bažok ◽

Darija Lemic

Keyword(s):

Colorado Potato Beetle ◽

Leptinotarsa Decemlineata ◽

New Technologies ◽

Population Genomics ◽

Resistance Management ◽

Successful Implementation ◽

Nucleotide Polymorphisms ◽

Functional Studies ◽

Potato Beetle ◽

Leptinotarsa Decemlineata Say

Colorado potato beetle, CPB (Leptinotarsa decemlineata Say), is one of the most important pests of the potato globally. Larvae and adults can cause complete defoliation of potato plant leaves and can lead to a large yield loss. The insect has been successfully suppressed by insecticides; however, over time, has developed resistance to insecticides from various chemical groups, and its once successful control has diminished. The number of available active chemical control substances is decreasing with the process of testing, and registering new products on the market are time-consuming and expensive, with the possibility of resistance ever present. All of these concerns have led to the search for new methods to control CPB and efficient tools to assist with the detection of resistant variants and monitoring of resistant populations. Current strategies that may aid in slowing resistance include gene silencing by RNA interference (RNAi). RNAi, besides providing an efficient tool for gene functional studies, represents a safe, efficient, and eco-friendly strategy for CPB control. Genetically modified (GM) crops that produce the toxins of Bacillus thuringiensis (Bt) have many advantages over agro-technical, mechanical, biological, and chemical measures. However, pest resistance that may occur and public acceptance of GM modified food crops are the main problems associated with Bt crops. Recent developments in the speed, cost, and accuracy of next generation sequencing are revolutionizing the discovery of single nucleotide polymorphisms (SNPs) and field of population genomics. There is a need for effective resistance monitoring programs that are capable of the early detection of resistance and successful implementation of integrated resistance management (IRM). The main focus of this review is on new technologies for CPB control (RNAi) and tools (SNPs) for detection of resistant CPB populations.

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Double-stranded RNA in exosomes: Potential systemic RNA interference pathway in the Colorado potato beetle, Leptinotarsa decemlineata

Journal of Asia-Pacific Entomology ◽

10.1016/j.aspen.2020.09.012 ◽

2020 ◽

Vol 23 (4) ◽

pp. 1160-1164

Author(s):

June-Sun Yoon ◽

Kyungbo Kim ◽

Subba Reddy Palli

Keyword(s):

Rna Interference ◽

Colorado Potato Beetle ◽

Leptinotarsa Decemlineata ◽

Double Stranded Rna ◽

Potato Beetle ◽

Systemic Rna

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Selection for high levels of resistance to double-stranded RNA (dsRNA) in Colorado potato beetle (Leptinotarsa decemlineata Say) using non-transgenic foliar delivery

Scientific Reports ◽

10.1038/s41598-021-85876-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Swati Mishra ◽

James Dee ◽

William Moar ◽

Jodi Dufner-Beattie ◽

James Baum ◽

...

Keyword(s):

Colorado Potato Beetle ◽

Leptinotarsa Decemlineata ◽

Insect Pest ◽

Resistance Management ◽

Cross Resistance ◽

Recessive Trait ◽

Management Tools ◽

Regulatory Review ◽

Atpase Subunit ◽

Potato Beetle

AbstractInsecticidal double-stranded RNAs (dsRNAs) silence expression of vital genes by activating the RNA interference (RNAi) mechanism in insect cells. Despite high commercial interest in insecticidal dsRNA, information on resistance to dsRNA is scarce, particularly for dsRNA products with non-transgenic delivery (ex. foliar/topical application) nearing regulatory review. We report the development of the CEAS 300 population of Colorado potato beetle (Leptinotarsa decemlineata Say) (Coleoptera: Chrysomelidae) with > 11,100-fold resistance to a dsRNA targeting the V-ATPase subunit A gene after nine episodes of selection using non-transgenic delivery by foliar coating. Resistance was associated with lack of target gene down-regulation in CEAS 300 larvae and cross-resistance to another dsRNA target (COPI β; Coatomer subunit beta). In contrast, CEAS 300 larvae showed very low (~ 4-fold) reduced susceptibility to the Cry3Aa insecticidal protein from Bacillus thuringiensis. Resistance to dsRNA in CEAS 300 is transmitted as an autosomal recessive trait and is polygenic. These data represent the first documented case of resistance in an insect pest with high pesticide resistance potential using dsRNA delivered through non-transgenic techniques. Information on the genetics of resistance and availability of dsRNA-resistant L. decemlineata guide the design of resistance management tools and allow research to identify resistance alleles and estimate resistance risks.

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A New Tool for Resistance Management: Baseline Toxicity, Ovicidal Activity, and Field Efficacy of the Novel Insecticide Tolfenpyrad on Colorado Potato Beetle, <i>Leptinotarsa decemlineata</i>

Advances in Entomology ◽

10.4236/ae.2015.34017 ◽

2015 ◽

Vol 03 (04) ◽

pp. 139-147 ◽

Cited By ~ 1

Author(s):

Adam F. Wimer ◽

Christopher R. Philips ◽

Thomas P. Kuhar ◽

James C. Adams ◽

Zsofia Szendrei

Keyword(s):

Colorado Potato Beetle ◽

Leptinotarsa Decemlineata ◽

Resistance Management ◽

The Novel ◽

Ovicidal Activity ◽

Potato Beetle ◽

Field Efficacy

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AFLP-Based Genetic Linkage Map of the Colorado Potato Beetle Leptinotarsa decemlineata: Sex Chromosomes and a Pyrethroid-Resistance Candidate Gene

Genetics ◽

10.1093/genetics/158.2.695 ◽

2001 ◽

Vol 158 (2) ◽

pp. 695-700 ◽

Cited By ~ 1

Author(s):

David J Hawthorne

Keyword(s):

Candidate Gene ◽

Linkage Map ◽

Colorado Potato Beetle ◽

Leptinotarsa Decemlineata ◽

Genetic Linkage ◽

Genetic Linkage Map ◽

Sex Chromosome ◽

Pyrethroid Resistance ◽

Codominant Markers ◽

Potato Beetle

Abstract A genetic linkage map was constructed from an intraspecific cross of the Colorado potato beetle, Leptinotarsa decemlineata. This is an initial step toward mapping the loci that underlie important phenotypes associated with insect adaptation to an agroecosystem. The map was made with 172 AFLP and 10 anonymous codominant markers segregating among 74 backcross (BC1) individuals. Markers were mapped to 18 linkage groups and a subset of the markers with a mean intermarker distance of 11.1 cM is presented. A pyrethroid-resistance candidate gene, LdVssc1, was placed onto the map as well. The sex chromosome was identified by exploiting the XO nature of sex determination in this species using patterns of variation at LdVssc1 and the codominant markers.

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