Harmonic Radar: Assessing the Impact of Tag Weight on Walking Activity of Colorado Potato Beetle, Plum Curculio, and Western Corn Rootworm

SUMMARYThe present study is focused on the potential occurrence of the Colorado potato beetle (Leptinotarsa decemlineata, Say 1824), an important potato pest, and the European corn borer (Ostrinia nubilalis, Hübner 1796), the most important maize pest, during climate change. Estimates of the current potential distribution of both pest species as well as their distribution in the expected climate conditions are based on the CLIMEX model. The study covers central Europe, including Austria, the Czech Republic, Hungary, and parts of Germany, Poland, Romania, Slovakia, Switzerland, Ukraine, Slovenia, the northern parts of Serbia, parts of Croatia and northern Italy. The validated model of the pests’ geographical distribution was applied within the domain of the regional climate model (RCM) ALADIN, at a resolution of 10 km. The weather series that was the input for the CLIMEX model was prepared by a weather generator (WG) which was calibrated with the RCM-simulated weather series (for the period of 1961–90). To generate a weather series for two future time periods (2021–50 and 2071–2100), the WG parameters were modified according to 12 climate change scenarios produced by the pattern scaling method. The standardized scenarios derived from three global climate models (HadCM, NCAR-PCM and ECHAM) were scaled by low, middle and high values of global temperature change estimated by the Model for the Assessment of Greenhouse-gas Induced Climate Change (MAGICC) model (assuming three combinations of climatic sensitivity and emission scenarios). The results of present study suggest the likely widening of the pests’ habitats and an increase in the number of generations per year. According to the HadCM-high scenario, the area of arable land affected by a third generation per season of Colorado potato beetle in 2050 is c. 45% higher, and by a second generation of the European corn borer is nearly 61% higher, compared to present levels.

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Competition of Transgenic Volunteer Corn with Soybean and the Effect on Western Corn Rootworm Emergence

Weed Science ◽

10.1614/ws-d-11-00133.1 ◽

2012 ◽

Vol 60 (2) ◽

pp. 193-198 ◽

Cited By ~ 32

Author(s):

P. Marquardt ◽

C. Krupke ◽

W. G. Johnson

Keyword(s):

Yield Loss ◽

Larval Survival ◽

Western Corn Rootworm ◽

Growth And Yield ◽

Corn Rootworm ◽

Soybean Yield ◽

Emergence Traps ◽

Volunteer Corn ◽

Corn Plants ◽

The Impact

Glyphosate-resistant (GR) volunteer corn has emerged as a problematic weed in corn:soybean rotational systems, partly because of the rapid increase in adoption of corn hybrids that contain traits for both glyphosate and insect resistance. Volunteer GR corn can decrease soybean yields. The objectives of this study were to quantify the impact of volunteer corn on soybean growth and yield and determine how volunteer corn densities affect western corn rootworm (WCR) emergence. Volunteer corn seed was hand-planted at targeted densities of 0.5, 2, 4, 8, 12, and 16 seeds m−2at soybean planting and 21 d after planting to evaluate both early- and late-emerging cohorts. WCR emergence was assessed with the use of field emergence traps placed over individual corn plants in the 0.5- and 16-plants-m−2plots in 2008 and 2009. In 2010, WCR emergence traps were also placed over individual and clumped volunteer corn plants at densities of two and eight plants m−2. Soybean yield reductions ranged from 10 to 41% where early-emerging volunteer corn densities ranged from 0.5 to 16 plants m−2. No soybean yield loss occurred with the late-emerging cohort of volunteer corn. Twice as many adult WCRs emerged from a single volunteer corn plant growing at densities of 8 and 16 plants m−2, compared with plots containing 0.5 and 2 plants m−2. These results demonstrate that controlling volunteer corn will not only prevent soybean yield loss, but also may reduce the risk of WCR larval survival after exposure to Bt (Bacillus thuringiensisBerliner derived) corn.

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Effects of Bioinsecticidal Aegerolysin-Based Cytolytic Complexes on Non-Target Organisms

Toxins ◽

10.3390/toxins13070457 ◽

2021 ◽

Vol 13 (7) ◽

pp. 457

Author(s):

Anastasija Panevska ◽

Gordana Glavan ◽

Anita Jemec Kokalj ◽

Veronika Kukuljan ◽

Tomaž Trobec ◽

...

Keyword(s):

Pore Formation ◽

Western Corn Rootworm ◽

Corn Rootworm ◽

Beneficial Arthropods ◽

Arthropod Species ◽

Protein Partner ◽

Potato Beetle ◽

Pore Complexes ◽

Mammalian Toxicity ◽

Specific Membrane

Aegerolysin proteins ostreolysin A6 (OlyA6), pleurotolysin A2 (PlyA2) and erylysin A (EryA) produced by the mushroom genus Pleurotus bind strongly to an invertebrate-specific membrane sphingolipid, and together with a protein partner pleurotolysin B (PlyB), form transmembrane pore complexes. This pore formation is the basis for the selective insecticidal activity of aegerolysin/PlyB complexes against two economically important coleopteran pests: the Colorado potato beetle and the western corn rootworm. In this study, we evaluated the toxicities of these aegerolysin/PlyB complexes using feeding tests with two ecologically important non-target arthropod species: the woodlouse and the honey bee. The mammalian toxicity of the EryA/PlyB complex was also evaluated after intravenous administration to mice. None of the aegerolysin/PlyB complexes were toxic against woodlice, but OlyA6/PlyB and PlyA2/PlyB were toxic to honeybees, with 48 h mean lethal concentrations (LC50) of 0.22 and 0.39 mg/mL, respectively, in their food. EryA/PlyB was also tested intravenously in mice up to 3 mg/kg body mass, without showing toxicity. With no toxicity seen for EryA/PlyB for environmentally beneficial arthropods and mammals at the tested concentrations, these EryA/PlyB complexes are of particular interest for development of new bioinsecticides for control of selected coleopteran pests.

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The effects of drought stress and western corn rootworm feeding on maize root biology

10.32469/10355/64002 ◽

2010 ◽

Author(s):

◽

Kristen A. Leach

Keyword(s):

Gene Expression ◽

Mirna Expression ◽

Expression Patterns ◽

Primary Root ◽

Diabrotica Virgifera Virgifera ◽

Western Corn Rootworm ◽

Specific Response ◽

Corn Rootworm ◽

Defense Genes ◽

The Impact

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] Drought and western corn rootworm (WCR), Diabrotica virgifera virgifera, can have substantial impacts on the potential yield of maize, Zea may L. Maize lines were selected to survey the level of diversity available for primary root elongation maintenance under water stress and three WCR-related traits: WCR damage, root size, and root regrowth. Data analysis suggests that lines belonging to the Tropical/Semi-tropical population structure group are a significant source of alleles which would improve resistance/tolerance to these stressors. Further analysis of the WCR trait data found significant correlations with agronomically important traits related to plant maturity, confirming the impact of maize phenology on WCR damage. This indicates that phase change or changes in biochemical pathways as the plant matures may serve as additional criteria to effectively select germplasm that is resistant/tolerant to WCR feeding. In an effort to identify maize genes responsible for defense against WCR herbivory, a transcriptome analysis discovered that the presence of an endosymbiont, Wolbachia, down-regulated the expression of defense genes. Gene expression time courses suggest WCR elicits a response to herbivory by WCR+wb which was confirmed by a more extensive analysis of the microarray data. Maize defense genes were found to be down-regulated in agreement with the previous study. Transcriptional down-regulation may be the result of transposable element interference or post-transcriptional regulation by small RNAs, i.e. siRNAs or miRNAs. Three classes of miRNA were identified based on their response to WCR+wb, WCR-wb, and control treatments in the CRW3 germplasm; WCR-specific response, Wolbachia-specific response, and generalized defense response. Models based on the miRNA expression patterns along with information from the literature about their targets and downstream effects enabled us to predict phenotypes based on miRNA mediated-changes in gene expression. Results of the GO term enrichment analysis together with miRNA expression analysis support miRNA-mediated post-translational modification as one mechanism underlying the Wolbachia-associated changes in maize gene expression.

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