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Full-Text Articles in Life Sciences
Using Adults To Monitor Rnai Susceptibility Of Western Corn Rootworm, Diabrotica Virgifera Virgifera Leconte, Field Populations, Matthew Welter
Using Adults To Monitor Rnai Susceptibility Of Western Corn Rootworm, Diabrotica Virgifera Virgifera Leconte, Field Populations, Matthew Welter
Department of Entomology: Dissertations, Theses, and Student Research
The western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, is the most damaging corn pest in the U.S. Corn Belt, costing producers over $1 billion annually in control and damage costs. Currently, corn producers rely on three control strategies for WCR management: crop rotation, chemical insecticides, and transgenic corn expressing Bacillus thuringiensis Berliner (Bt) proteins. Populations of WCR have evolved resistance to all of these tactics, limiting effective control strategies for producers. RNA interference (RNAi), is the newest mode of action developed for WCR management. In July 2017, the first RNAi plant-incorporated protectant (PIP) corn product was approved for production …
Characterization Of The Natural Enemy Community, With Emphasis On Entomopathogens, For Management Of Western Corn Rootworm (Diabrotica Virgifera Virgifera) In West Central Nebraska, Camila Oliveira-Hofman
Characterization Of The Natural Enemy Community, With Emphasis On Entomopathogens, For Management Of Western Corn Rootworm (Diabrotica Virgifera Virgifera) In West Central Nebraska, Camila Oliveira-Hofman
Department of Entomology: Dissertations, Theses, and Student Research
Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae),the western corn rootworm (WCR), is a major pest of corn (Zea mays L.) in the United States and Europe. WCR management options comprise mainly transgenic hybrids, insecticide applications and crop rotation. WCR is highly adaptable to management practices and field-evolved resistance to transgenic corn, insecticides and crop rotation in the United States Corn Belt has been reported. Therefore, the motivation for this project was to look into alternative options for WCR management. The goal of this dissertation is to characterize the natural enemies from irrigated commercial cornfields in Nebraska and examine their …
Spatial Variation In Western Corn Rootworm (Coleoptera: Chrysomelidae) Susceptibility To Bacillus Thuringiensis Corn Events In Nebraska, Jordan D. Reinders
Spatial Variation In Western Corn Rootworm (Coleoptera: Chrysomelidae) Susceptibility To Bacillus Thuringiensis Corn Events In Nebraska, Jordan D. Reinders
Department of Entomology: Dissertations, Theses, and Student Research
The western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, is an economically important pest species of field corn (Zea mays L.) in the U.S. Corn Belt. Yield losses and control costs exceed greater than $1 billion annually. Over the past 10+ years, growers have adopted transgenic corn hybrids expressing rootworm-active Bacillus thuringiensis (Bt) proteins as a primary WCR management tactic. Field-evolved resistance to Cry3Bb1 and mCry3A proteins expressed in single-trait Bt hybrids has been confirmed in some areas of Nebraska. Growers have used different tactics as needed to prevent or mitigate resistance, resulting in a mosaic of selection pressure placed …
Effects Of A Corn Root Defense Substance On Western Corn Rootworm Diabrotica Virgifera Virgifera Leconte Larvae, Zixiao Zhao
Effects Of A Corn Root Defense Substance On Western Corn Rootworm Diabrotica Virgifera Virgifera Leconte Larvae, Zixiao Zhao
Department of Entomology: Dissertations, Theses, and Student Research
The objectives of this research were to evaluate the effects of hydroxamic acids, a group of corn root defense substances on western corn rootworm (Diabrotica virgifera virgifera LeConte) larvae and identify putative molecular mechanisms for hydroxamic acid detoxification. Corn line 428G carries a homozygous mutant bx1 gene, which makes it unable to synthesis hydroxamic acids. In contrast, H88 is the wild type parental line of 428G and is able to synthesize hydroxamic acids. Larvae were fed on 428G and H88 roots for 7 days for comparison. No significant difference was observed in growth, development, or survival rate. A RNA-Sequencing …
Characterization Of Resistance To The Cry1f Toxin From Bacillus Thuringiensis In Resistant Fall Armyworm, Spodoptera Frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) From Puerto Rico, Ana Maria Velez
Department of Entomology: Dissertations, Theses, and Student Research
Transgenic corn expressing Cry1F protein from Bacillus thuringiensis Berliner has been registered for Spodoptera frugiperda control since 2003. Unexpected damage to Cry1F corn was reported in 2006 in Puerto Rico and Cry1F resistance in S. frugiperda was documented. The inheritance of Cry1F resistance was characterized in a S. frugiperda resistant strain from Puerto Rico which displayed >387-fold resistance to Cry1F. Concentration-response bioassays of reciprocal crosses of resistant and susceptible parental populations indicated that resistance is recessive and autosomal. Bioassays of the backcross of the F1 generation crossed with the resistant parental strain suggest that a single locus is responsible …