title: A transgenic approach for controlling Lygus in cotton.
abstract: Lygus species of plant-feeding insects have emerged as economically important pests of cotton in the United States. These species are not controlled by commercial Bacillus thuringiensis (Bt) cotton varieties resulting in economic losses and increased application of insecticide. Previously, a Bt crystal protein (Cry51Aa2) was reported with insecticidal activity against Lygus spp. However, transgenic cotton plants expressing this protein did not exhibit effective protection from Lygus feeding damage. Here we employ various optimization strategies, informed in part by protein crystallography and modelling, to identify limited amino-acid substitutions in Cry51Aa2 that increase insecticidal activity towards Lygus spp. by >200-fold. Transgenic cotton expressing the variant protein, Cry51Aa2.834_16, reduce populations of Lygus spp. up to 30-fold in whole-plant caged field trials. One transgenic event, designated MON88702, has been selected for further development of cotton varieties that could potentially reduce or eliminate insecticide application for control of Lygus and the associated environmental impacts.
authors.affiliation: Monsanto Company, Chesterfield, Missouri 63017, USA.
authors.forename: Anilkumar
authors.initials: A
authors.lastname: Gowda
authors.affiliation: Monsanto Company, Chesterfield, Missouri 63017, USA.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Rydel
authors.affiliation: Monsanto Company, Chesterfield, Missouri 63017, USA.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Wollacott
authors.affiliation: Monsanto Company, Chesterfield, Missouri 63017, USA.
authors.forename: Robert S
authors.initials: RS
authors.lastname: Brown
authors.affiliation: Monsanto Company, Chesterfield, Missouri 63017, USA.
authors.forename: Waseem
authors.initials: W
authors.lastname: Akbar
authors.affiliation: Monsanto Company, Chesterfield, Missouri 63017, USA.
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Clark
authors.affiliation: Monsanto Company, Chesterfield, Missouri 63017, USA.
authors.forename: Stanislaw
authors.initials: S
authors.lastname: Flasinski
authors.affiliation: Monsanto Company, Chesterfield, Missouri 63017, USA.
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Nageotte
authors.affiliation: Monsanto Company, Chesterfield, Missouri 63017, USA.
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Read
authors.affiliation: Monsanto Company, Chesterfield, Missouri 63017, USA.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Shi
authors.affiliation: Monsanto Company, Chesterfield, Missouri 63017, USA.
authors.forename: Brent J
authors.initials: BJ
authors.lastname: Werner
authors.affiliation: Monsanto Company, Chesterfield, Missouri 63017, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Pleau
authors.affiliation: Monsanto Company, Chesterfield, Missouri 63017, USA.
authors.forename: James A
authors.initials: JA
authors.lastname: Baum
mesh_terms: D000818:Animals; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D001681:Biological Assay; D004731:Endotoxins / Q000737:chemistry / Q000378:metabolism; D003368:Gossypium / Q000235:genetics* / Q000469:parasitology*; D006460:Hemolysin Proteins / Q000737:chemistry / Q000378:metabolism; D020062:Heteroptera / Q000502:physiology*; D050505:Mutant Proteins / Q000378:metabolism; D010572:Pest Control, Biological; D030821:Plants, Genetically Modified
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; D050505:Mutant Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis