Agronomy and Crop Sciences Commons^™

Susceptibility Of The Fall Armyworm, Spodoptera Frugiperda (Lepidoptera: Noctuidae), At Santa Isabel, Puerto Rico, To Different Insecticides, Difabachew K. Belay, Randy M. Huckaba, John E. Foster

Department of Entomology: Faculty Publications

The fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith), is a polyphagous migratory pest, which is endemic to the Western Hemisphere and attacks more than 80 plant species including maize, sorghum, cotton, rice, millet, peanut, alfalfa, and other cultivated and wild plant species. Presence of multiple generations and the ability to migrate and feed on a wide range of host plants makes FAW one of the most severe economic pests throughout the Western Hemisphere. In corn, yield losses due to FAW damage can reach up to 32% in the United States and 45–60% in Nicaragua. Insecticides are used as major …

Insecticidal Control Of Bemisia Tabaci (Hemiptera: Aleyrodidae) Transmitting Carlavirus On Soybeans And Detection Of The Virus In Alternate Hosts, Difabachew K. Belay, Randy M. Huckaba, Axel M. Ramirez, Jose C. V. Rodrigues, John E. Foster

Department of Entomology: Faculty Publications

A Carlavirus transmitted by Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is an important disease of soybean nurseries in Puerto Rico causing substantial germplasm losses. Insecticide bioassay experiments were conducted at Dow AgroSciences (DAS) Research Station, Santa Isabel, Puerto Rico, either by spraying insecticides on B. tabaci infested soybean leaves or introducing B. tabaci adults onto insecticide-sprayed soybean leaves. Moreover, host plants were surveyed to detect the virus in overwintering hosts that serve as a source of inoculums. The direct spray experiment showed that Nuprid 2F (Imidacloprid), Capture 2 EC (Bifenthrin), Thionex (Endosulfan), Lannate LV (Methomyl), and Dimethoate gave good level ( …

Genetic Differentiation Of Western Corn Rootworm Populations (Coleoptera: Chrysomelidae) Relative To Insecticide Resistance, Hong Chen, Haichuan Wang, Blair D. Siegfried

Department of Entomology: Faculty Publications

Abstract

As the single most important pest of field corn, Zea mays L., throughout most of the Corn Belt, the western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), has undergone repeated selection for resistance to a variety of insecticides that persist widely among Nebraska populations. In this study, we used 11 microsatellite markers to genotype two populations with high levels of resistance to methyl-parathion and aldrin (Polk and Stromsburg), two populations with low and intermediate levels of resistance (Mead and Clay Center) from Nebraska, and one population from outside the Corn Belt (Safford, Arizona). The genetic diversity measured by …

Spatial Genetic Variation Among Spodoptera Frugiperda (Lepidoptera: Noctuidae) Sampled From The United States, Puerto Rico, Panama, And Argentina, Difabachew K. Belay, Pete L. Clark, Steven R. Skoda, David J. Isenhour, Jaime Molina-Ochoa, Claudia Gianni, John E. Foster

Department of Entomology: Faculty Publications

Spatial genetic variability of the fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), was studied by collecting samples from 31 locations in the United States, Argentina, Panama, and Puerto Rico, and then using amplified fragment length polymorphism to detect genetic variation. Analysis of molecular variance showed significant genetic variation in fall armyworm among all (28%) sample locations and individuals within (71%) sample locations; genetic variation of fall armyworm was minimal between sample locations grouped into regions. The pairwise fixation index (F_ST) comparisons showed significant genetic differentiation (0.288) among the 31 locations. However, dendrograms of results from cluster …

Mortality Impact Of Mon863 Transgenic Maize Roots On Western Corn Rootworm Larvae In The Field, T. L. Clark, D. L. Frank, B. W. French, Lance J. Meinke, D. Moellenbeck, T. T. Vaughn, B. E. Hibbard

Department of Entomology: Faculty Publications

Mortality of western corn rootworm (Diabrotica virgifera virgifera LeConte) due to feeding on MON863 transgenic maize (Zea mays L.) expressing the Cry3Bb1 protein was evaluated at three Missouri sites in both 2003 and 2004 and at one site each in South Dakota, Nebraska, and Iowa in 2004. To do this, survivorship relative to survivorship on isoline maize (i.e., the same genetic background, but without Cry3Bb1) was evaluated. Comparisons were made using low (1650–2500 eggs/m) and high (3300–3500 eggs/m) western corn rootworm egg densities. Significantly fewer beetles were recovered from MON863 than from isoline maize. Emergence from MON863 as …

Distribution Of Genes And Repetitive Elements In The Diabrotica Virgifera Virgifera Genome Estimated Using Bac Sequencing, Brad S. Coates, Analiza P. Alves, Haichuan Wang, Kimberly K. O. Walden, B. Wade French, Nicholas J. Miller, Craig A. Abel, Hugh M. Robertson, Thomas W. Sappington, Blair D. Siegfried

Department of Entomology: Faculty Publications

Feeding damage caused by the western corn rootworm, Diabrotica virgifera virgifera, is destructive to corn plants in North America and Europe where control remains challenging due to evolution of resistance to chemical and transgenic toxins. A BAC library, DvvBAC1, containing 109,486 clones with 104 ± 34.5 kb inserts was created, which has an ~4.56X genome coverage based upon a 2.58 Gb (2.80 pg) flow cytometry-estimated haploid genome size. Paired end sequencing of 1037 BAC inserts produced 1.17Mb of data (~0.05% genome coverage) and indicated ~9.4 and 16.0% of reads encode, respectively, endogenous genes and transposable elements (TEs). …

Using Sex Pheromone Traps In The Decision-Making Process For Pesticide Application Against Fall Armyworm (Spodoptera Frugiperda [Smith] [Lepidoptera: Noctuidae]) Larvae In Maize, Ivan Cruz, Maria De Lourdes Corrêa Figueiredo, Rafael Braga Da Silva, Ivana Fernandes Da Silva, Cristiane De Souza Paula, John E. Foster

Department of Entomology: Faculty Publications

The fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), is a major pest of maize and frequently demands control measures. The timing of insecticide application is a key factor in determining its efficiency, so an experiment was designed to investigate this. Application of insecticide was based on three criteria: (i) the number of trap-caught moths in a Delta-type trap with a commercial sex pheromone lure placed in the center of the target area, soon after plant emergence; (ii) the percentage of plants exhibiting pinhole-type damage (10% or 20%), and (iii) the percentage of plants exhibiting shot hole–type damage (10% or 20%) …