Life Sciences Commons^™

Co-Transcriptomic Analysis Of The Maize–Western Corn Rootworm Interaction, Lise Pingault, Saumik Basu, Neetha N. Vellichirammal, William Paul Williams, Gautam Sarath, Joe Louis

Department of Entomology: Faculty Publications

The Western corn rootworm (WCR; Diabrotica virgifera virgifera) is an economically important belowground pest of maize. Belowground feeding by WCR is damaging because it weakens the roots system, diminishes nutrient uptake, and creates entry points for fungal and bacterial pathogens and increases lodging, all of which can significantly suppress maize yields. Previously, it was demonstrated that belowground herbivory can trigger plant defense responses in the roots and the shoots, thereby impacting intraplant communication. Although several aspects of maize-WCR interactions have been reported, co-transcriptomic remodeling in the plant and insect are yet to be explored. We used a maize genotype, …

Impact Of Maize Hormonal Interactions On The Performance Of Spodoptera Frugiperda In Plants Infected With Clavibacter Michiganensis Subsp. Nebraskensis, Karen Da Silva, Sydney E. Everhart, Joe Louis

Department of Entomology: Faculty Publications

In nature, plants interact with multiple organisms, below and aboveground. Although interactions of plants with single biotic stressors are well characterized, knowledge of how the immune system responds to multiple biotic stressors is lacking. It is known that the two most important pathways involved in the plant immune defenses are jasmonic acid (JA) and salicylic acid (SA). The crosstalk between these plant hormonal signaling pathways seems to fine-tune the plant responses to different stressors. In this study, we characterized maize (Zea mays) hormonal interactions under the attack of two economically important pests: the bacterial pathogen that causes Goss’s …

Transcriptomic And Volatile Signatures Associated With Maize Defense Against Corn Leaf Aphid, Lise Pingault, Suresh Varsani, Nathan Palmer, Swayamjit Ray, W. Paul Williams, Dawn S. Luthe, Jared G. Ali, Gautam Sarath, Joe Louis

Department of Entomology: Faculty Publications

Background: Maize (Zea mays L.) is a major cereal crop, with the United States accounting for over 40% of the worldwide production. Corn leaf aphid [CLA; Rhopalosiphum maidis (Fitch)] is an economically important pest of maize and several other monocot crops. In addition to feeding damage, CLA acts as a vector for viruses that cause devastating diseases in maize. We have shown previously that the maize inbred line Mp708, which was developed by classical plant breeding, provides heightened resistance to CLA. However, the transcriptomic variation conferring CLA resistance to Mp708 has not been investigated.

Results: In this study, we contrasted …

Aboveground Herbivory Influences Belowground Defense Responses In Maize, Lise Pingault, Saumik Basu, Prince Zogli, W. Paul Williams, Nathan Palmer, Gautam Sarath, Joe Louis

Department of Entomology: Faculty Publications

The European corn borer (ECB; Ostrinia nubilalis) is an economically damaging insect pest of maize (Zea mays L.), an important cereal crop widely grown globally. Among inbred lines, the maize genotype Mp708 has shown resistance to diverse herbivorous insects, although several aspects of the defense mechanisms of Mp708 plants are yet to be explored. Here, the changes in root physiology arising from short-term feeding by ECB on the shoot tissues of Mp708 plants was evaluated directly using transcriptomics, and indirectly by monitoring changes in growth of western corn rootworm (WCR; Diabrotica virgifera virgifera) larvae. Mp708 defense responses …

High Plains Wheat Mosaic Virus: An Enigmatic Disease Of Wheat And Corn Causing The High Plains Disease, Satyanarayana Tatineni, Gary Hein

Department of Entomology: Faculty Publications

Brief history: In 1993, severe mosaic and necrosis symptoms were observed on corn (maize) and wheat from several Great Plains states of the USA. Based on the geographical location of infections, the disease was named High Plains disease and the causal agent was tentatively named High Plains virus. Subsequently, researchers renamed this virus as maize red stripe virus and wheat mosaic virus to represent the host and symptom phenotype of the virus. After sequencing the genome of the pathogen, the causal agent of High Plains disease was officially named as High Plains wheat mosaic virus. Hence, High Plains virus, …

Evaluation Of Foliar Insecticides For The Control Of Western Bean Cutworm In Field Corn, 2018, Katharine A. Swoboda-Bhattarai, Samantha R. Daniel, Julie A. Peterson

West Central Research and Extension Center, North Platte

The objectives of this field trial were to evaluate the efficacy of single applications of foliar insecticides at preventing feeding damage by the western bean cutworm (WBC), an important pest of corn and dry beans that has undergone a rapid range expansion into the eastern Corn Belt during the last 18 yr. This study was conducted within the historic range of WBC, at the University of Nebraska-Lincoln’s Henry J. Stumpf International Wheat Center in Perkins County, NE (40.856851°N, −101.701335°W). An RCB design with a total of 16 treatments (including an untreated check) and four replications was used. Plots measured 20 …

Evaluation Of Seed Treatments And At-Plant Soil Insecticides For The Control Of Wireworms (Coleoptera: Elateridae) In Field Corn, 2015, Kayla A. Mollet, Jonas Victor De Macedo, Grace E. Hirzel, C. Oliveira-Hofman, Julie A. Peterson

Department of Entomology: Faculty Publications

Wireworms are an important pest of corn, other field crop seedlings, and vegetables and can cause significant damage if not controlled. This field trial was established to evaluate the efficacy of neonicotinoid seed treatments and in-furrow soil insecticides to protect seedling field corn under a heavy wireworm pressure scenario. The trial was conducted on a commercial production field in Perkins County near Madrid, NE (40.781993° N, −101.463666° W). The field was selected for its likelihood to have heavy wireworm pressure due to the following: 1) past farmer observations of crop damage when planted to field corn in 2012; 2) sandy …

Evaluation Of Foliar Insecticides For The Control Of Western Bean Cutworm In Field Corn, 2017, Katharine A. Swoboda-Bhattarai, Grace E. Hirzel, Julie A. Peterson

Department of Entomology: Faculty Publications

The objective of this field trial was to evaluate the efficacy of a single application of foliar insecticides at preventing feeding damage by the western bean cutworm (WBC), an important pest of corn and dry beans. Direct feeding by WBC larvae on developing kernels in the ear can result in yield loss, whereas WBC infestation can also lead to secondary fungal infections. WBC has undergone a rapid range expansion into the eastern Corn Belt within the last 16 yr. This study was conducted within the historic range of WBC, at the University of Nebraska-Lincoln’s Henry J. Stumpf International Wheat Center …

Performance Of Seed Treatments And In-Furrow At-Plant Insecticides For Protection Against Cry3bb1-Resistant Western Corn Rootworm, 2015, Jonas Victor De Macedo,, Kayla A. Mollet, Julie A. Peterson

Department of Entomology: Faculty Publications

The western corn rootworm is an important pest of corn that can compromise yield by feeding on plant roots during its larval stage. WCRW management has been complicated by the development of resistance in some regions, including Nebraska, to transgenic Bacillus thuringiensis (Bt) traits, particularly the protein Cry3Bb1, which confers cross-resistance to mCry3A. A field trial was established to evaluate the efficacy of neonicotinoid seed treatments in combination with in-furrow insecticides on a corn hybrid expressing mCry3A Bt proteins against corn rootworm in an area with a history of rootworm resistance. The trial was conducted in a farmer’s field in …

Evaluation Of Foliar Insecticides For The Control Of Western Bean Cutworm In Field Corn, 2015, Débora G. Montezano, Kayla A. Mollet, Grace E. Hirzel, Julie A. Peterson

Department of Entomology: Faculty Publications

The western bean cutworm (WBC) is an important pest of corn and dry beans. This study was conducted within the historic range of WBC in western Nebraska; however, it has undergone a rapid range expansion into the eastern Corn Belt within the last 16 years. This field trial was established to evaluate the efficacy of a single application of foliar insecticides against this pest to prevent feeding damage to non-Bt corn ears. The trial was located at the University of Nebraska-Lincoln’s West Central Water Resources Field Laboratory in Keith County, Nebraska, USA (41.160246° N, –102.035695° W). A RCB design with …

Evaluation Of Foliar Insecticides For The Control Of Western Bean Cutworm In Field Corn, 2016, Débora G. Montezano, Kayla A. Mollet, Grace E. Hirzel, Julie A. Peterson

Department of Entomology: Faculty Publications

The western bean cutworm (WBC) is an important pest of corn and dry beans. In addition to yield loss due to direct feeding on developing kernels in the ear, WBC infestation can also lead to secondary fungal infections. This study was conducted within the historic range of WBC in western Nebraska; however, it has undergone a rapid range expansion into the eastern Corn Belt within the last 16 years. This field trial was established to evaluate the efficacy of a single application of foliar insecticides against this pest to prevent feeding damage to non-Bt corn ears. The trial was located …

Lessons From The Far End: Caterpillar Frass-Induced Defenses In Maize, Rice, Cabbage, And Tomato, Swayamjit Ray, Saumik Basu, Loren J. Rivera-Vega, Flor E. Acevedo, Joe Louis, Gary W. Felton, Dawn S. Luthe

Department of Entomology: Faculty Publications

Plant defenses to insect herbivores have been studied in response to several insect behaviors on plants such as feeding, crawling, and oviposition. However, we have only scratched the surface about how insect feces induce plant defenses. In this study, we measured frass-induced plant defenses in maize, rice, cabbage, and tomato by chewing herbivores such as European corn borer (ECB), fall armyworm (FAW), cabbage looper (CL), and tomato fruit worm (TFW). We observed that caterpillar frass induced plant defenses are specific to each host-herbivore system, and they may induce herbivore or pathogen defense responses in the host plant depending on the …

Estimation Of Efficacy Functions For Products Used To Manage Corn Rootworm Larval Injury, N A. Tinsley, P. D. Mitchell, Robert Wright, Lance J. Meinke, R. E. Estes, M. E. Gray

Department of Entomology: Faculty Publications

Maize, Zea mays L., is an economically important crop grown throughout the world. Corn rootworm, Diabrotica spp. (Coleoptera: Chrysomelidae), larvae constitute a significant economic threat to maize production in the United States, where yield losses and management costs associated with corn rootworm species exceed $1 billion annually. Furthermore, the introduction of the western corn rootworm, D. virgifera virgifera LeConte, into maize-producing regions of Europe has made managing corn rootworm larval injury an international concern. Larvae injure maize plants by feeding on root tissue and are the primary target of management activities. Products commonly used to protect root systems from injury …

Minute Pirate Bug (Orius Insidiosus Say) Populations On Transgenic And Non-Transgenic Maize Using Different Sampling Techniques, Santiago A. Palizada, Bamphitlhi Tiroesele, Difabachew B. Kondidie, Muhammad Irfan Ullah, Fatima Mustafa, Thomas E. Hunt, Pete L. Clark, Jaime Molina-Ochoa, Steven R. Skoda, John E. Foster

Department of Entomology: Faculty Publications

Field experiments were conducted to evaluate the populations of minute pirate bug [Orius insidiosus (Say)] using visual, sticky cards and destructive sampling techniques in transgenic and non-transgenic maize in three locations in Nebraska (Mead, Clay Center. and Concord) United States of America. during 2007 and 2008 . All sampling methods revealed significant counts of O. insidiosus on CP4 EPSPS maize plus an insecticide application for control of first generation O. nubilalis at R2 (blister) sampling period. Similarly, visual observations of O. insidiosus on Cry1Ab x Cry3Bb1 x CP4 EPSPS maize yielded significantly higher mean adult counts at R2 (blister) …

Induced Resistance Studied In Maize With The Fall Armyworm, Spodoptera Frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) And The Chemical Inducer Actigard, Stephen D. Danielson

Department of Entomology: Faculty Publications

Induced resistance has been defined as the "qualitative or quantitative enhancement of a plant's defense mechanisms against pests in response to extrinsic physical or chemical stimuli." (Kogan and Paxton, 1983). Physical stimuli can include infection by a pathogenic organism (Jorgensen et al, 1996; Morris et al, 1998) and feeding by insects (Felton and Eichenseer, 1999). Chemical stimuli include such organic compounds as salicylic acid (Hammerschmidt and Smith-Becker, 1999), jasmonic acid (Staswick and Lehman, 1999), and the commercially available Actigard® 50WG (Tally et al., 1999) (Syngenta Crop Protection, P.O. Box 18300, Greensboro, NC 27419). Actigard® 50WG is registered in the U.S. …

Efficacies Of Habitat Management Techniques In Managing Maize Stem Borers In Ethiopia, Difabachew K. Belay, John E. Foster

Department of Entomology: Faculty Publications

Habitat management techniques to control maize stem borers were tested in eastern (Melkassa and Mieso) and western (Sibu-Sire) Ethiopia. These techniques consisted of using mixed cropping of maize with haricot beans at different maize:bean ratios and a ‘‘push–pull’’ (PP) strategy utilizing Napier grass as a trap plant around maize plots as the ‘‘pull’’ and Desmodium in between maize rows as a deterrent or ‘‘push’’. In Melkassa, pest infestations were too low for the cropping system to significantly affect pests, plant damage and yields while in Mieso, where the pest densities were high, intercropping of maize with beans at ratios of …

Western Corn Rootworm ( Diabrotica Virgifera Virgifera Leconte) Population Dynamics, Lance Meinke, Thomas W. Sappington, David W. Onstad, Thomas Guillemaud, Nicholas Miller, Judit Komáromi, Nora Levay, Lorenzo Furlan, József Kiss, Ferenc Toth

Department of Entomology: Faculty Publications

1 The western corn rootworm Diabrotica virgifera virgifera LeConte is a major insect pest of field maize, Zea mays L. Larvae can cause substantial injury by feeding on maize roots. Larval feeding may destroy individual roots or root nodes, and reduce plant growth, stability, and yield. Costs associated with managing corn rootworms in continuous maize are annually one of the largest expenditures for insect management in the United States Corn Belt.

2 Even though D. virgifera virgifera has been studied intensively for over 50 years, there is renewed interest in the biology, ecology, and genetics of this species because of …

Parasitoids And Parasites Of Spodoptera Frugiperda (Lepidoptera: Noctuidae) In The Americas And Caribbean Basin: An Inventory, Jaime Molina-Ochoa, James E. Carpenter, Elvis A. Heinrichs, John E. Foster

Department of Entomology: Faculty Publications

An inventory of parasitoids and parasites of fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith), was conducted using references describing parasitized FAW eggs, larvae, pupae and adults collected from different crops or habitats throughout the Americas and the Caribbean Basin. The crops and countries where these parasites were reported occurring in the Americas is also inventoried. Maize was the crop where the FAW was more frequently collected followed by rice. Overall, Chelonus insularis (Cresson) had the broadest natural distribution in the Americas. For the North American region C. insulares , Chelonus sp., and Euplectrus platyhypenae (Howard) were the most …

Geostatistical Analysis Of The Small-Scale Distribution Of European Corn Borer (Lepidoptera: Crambidae) Larvae And Damage In Whorl Stage Corn, Robert J. Wright, Terry A. Devries, Linda J. Young, Keith J. Jarvi, Ronald C. Seymour

Department of Entomology: Faculty Publications

The small-scale spatial distribution of European corn borer, Ostrinia nubilalis (Hübner), larvae and damage in whorl stage corn, Zea mays L., was characterized using geostatistics. Spatial distribution of O. nubilalis larval feeding damage was studied at Clay Center, North Platte, and Concord, NE, during June-July 1992-1994, and spatial distribution of O. nubilalis larvae and damage was studied at Clay Center in June 1997. Semivariograms were calculated to model the change in spatial correlation with increasing distance between samples. Spatial distribution of larval damage during 1992-1994 was best described using a spherical model. Damage was spatially correlated among plants at distances …

Comparison Of Bt (Bacillus Thuringiensis Berliner) Maize And Conventional Measures For Control Of The European Corn Borer (Lepidoptera: Crambidae), Thomas L. Clark, J. E. Foster, Shripat T. Kamble, Elvis A. Heinrichs

Department of Entomology: Faculty Publications

Field experiments were conducted in 1997 to compare the efficacy Bt (Bacillus thuringiensis Berliner) maize hybrids and two conventional measures for control of the European corn borer, Ostrinia nubilalis (Hubner). Treatments consisted of transgenic Bt-maize hybrids and their non-Bt isolines, and isolines treated with a formulated Bt or permethrin insecticide. All control measures significantly reduced O. nubilalis damage in terms of tunnels per plant, length of tunneling, and larvae per plant. The following hierarchy in terms of O. nubilalis efficacy was observed: transgenic Bt > permethrin > formulated Bt > control. In most cases, transgenic Bt maize was most effective in preventing …

Insect Resistant Rice, Maize And Wheat Cultivars In Sustainable Agriculture, E. A. Heinrichs, J. E. Foster

Department of Entomology: Faculty Publications

The achievement of self sufficiency in food production is a major objective of governments throughout the world. Insects are one of the major constraints that limit the production of food crops. To mitigate losses due to insects. insect resistant cultivars are sought as a major tactic in the development of integrated pest management strategies. The integration of insect resistant cultivars with other pest management tactics contributes to crop pest management strategies that are environmentally and economically acceptable. Multiple pest resistant crop cultivars have high yield stability when grown in pest-infested environments. Significant progress on a global basis has been achieved …

End Of Tour Report Of E. A. Heinrichs, Piant Protection Advisor, Elvis A. Heinrichs

Department of Entomology: Faculty Publications

The opportunity to spend two years in Mysore (March 1970 to April 1972) working with various individuals involved in plant protection has been personally a rewarding and satisfying experience.

In general terms, the purpose of the Plant Protection Advisor was to identify the problems relating to plant protection which limit the spread and production of high yielding varieties and to assist in solving these problems .. The following Operational Work Plan, which was written by my predecessor, was followed and added to in order to achieve the overall objectives: 1. To promote widespread adoption of recommended plant protection practices. 2. …