title: Susceptibility of Helicoverpa zea (Lepidoptera: Noctuidae) Neonates to Diamide Insecticides in the Midsouthern and Southeastern United States.
abstract: Corn earworm, Helicoverpa zea (Boddie), is a significant pest of agroecosystems in the midsouthern and southeastern regions of the United States. These insects have developed resistance to, or inconsistent control has occurred with, most insecticide classes. With their unique mode of action, insecticides in the diamide class have become a key component in management of agriculturally important lepidopteran pests. In this study, field populations of H. zea were collected in the southern United States and compared to susceptible laboratory colonies to generate baseline concentration-mortality data. LC50 and LC90 values were generated for flubendiamide and chlorantraniliprole using neonates. To achieve equivalent levels of mortality, a higher concentration of flubendiamide was required compared to chlorantraniliprole. Flubendiamide LC50 values for H. zea ranged from 16.45 to 30.74 ng/ml, with a mean of 23.53 ng/ml. Chlorantraniliprole LC50 values for H. zea ranged from 2.94 to 4.22 ng/ml, with a mean of 3.66 ng/ml. Significant differences were observed for some field populations relative to the laboratory colony. For flubendiamide, five populations had greater LC50 values and two populations had lower LC50 values compared to the laboratory colony. For chlorantraniliprole, three populations had greater LC50 values and three populations had lower LC50 values compared to the laboratory colony. The response of these populations most likely represents natural variability among populations and does not indicate a significant shift in susceptibility of this species.
authors.affiliation: Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, MS 39762 (caa109@msstate.edu; acatchot@entomology.msstate.edu; Fmusser@entomology.msstate.edu; nkrishnan@entomology.msstate.edu).
authors.forename: A
authors.initials: A
authors.lastname: Adams
authors.affiliation: Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Delta Research and Extension Center (DREC), Stoneville, MS 38776 (jgore@drec.msstate.edu; dcook@drec.msstate.edu) jgore@drec.msstate.edu.
authors.forename: J
authors.initials: J
authors.lastname: Gore
authors.affiliation: Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, MS 39762 (caa109@msstate.edu; acatchot@entomology.msstate.edu; Fmusser@entomology.msstate.edu; nkrishnan@entomology.msstate.edu).
authors.forename: A
authors.initials: A
authors.lastname: Catchot
authors.affiliation: Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, MS 39762 (caa109@msstate.edu; acatchot@entomology.msstate.edu; Fmusser@entomology.msstate.edu; nkrishnan@entomology.msstate.edu).
authors.forename: F
authors.initials: F
authors.lastname: Musser
authors.affiliation: Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Delta Research and Extension Center (DREC), Stoneville, MS 38776 (jgore@drec.msstate.edu; dcook@drec.msstate.edu).
authors.forename: D
authors.initials: D
authors.lastname: Cook
authors.affiliation: Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, MS 39762 (caa109@msstate.edu; acatchot@entomology.msstate.edu; Fmusser@entomology.msstate.edu; nkrishnan@entomology.msstate.edu).
authors.forename: N
authors.initials: N
authors.lastname: Krishnan
authors.affiliation: Department of Plant and Soil Sciences, Mississippi State University, MS 3976 (tirby@pss.msstate.edu).
authors.forename: T
authors.initials: T
authors.lastname: Irby
mesh_terms: D000818:Animals; D001549:Benzamides / Q000494:pharmacology*; D007305:Insecticide Resistance; D007306:Insecticides / Q000494:pharmacology*; D007814:Larva / Q000187:drug effects / Q000235:genetics / Q000254:growth & development; D007928:Lethal Dose 50; D009036:Moths / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development; D015144:Southeastern United States; D013450:Sulfones / Q000494:pharmacology*; D062367:ortho-Aminobenzoates / Q000494:pharmacology*; D005466:Fluorocarbons; D010797:Phthalimides
chemical_list: D001549:Benzamides; D007306:Insecticides; D013450:Sulfones; D062367:ortho-Aminobenzoates; C517733:chlorantranilipole; C508762:flubendiamide; D005466:Fluorocarbons; D010797:Phthalimides
keywords: chlorantraniliprole; corn earworm; flubendiamide