title: Selection and Characterization of Bacillus thuringiensis (Berliner) (Eubacteriales: Bacillaceae) Strains for Ecdytolopha aurantiana (Lima) (Lepidoptera: Tortricidae) Control.
abstract: The citrus fruit borer, Ecdytolopha aurantiana (Lima, 1927) (Lepidoptera: Tortricidae), is responsible for major losses to the citrus industry because it causes rot and drop of fruits. The current study aimed to select and characterize Bacillus thuringiensis (Berliner, 1911) strains toxic to E. aurantiana. For this purpose, 47 B. thuringiensis strains were evaluated in selective bioassays using first instar larvae of E. aurantiana. The lethal concentration (LC50) of the most toxic strains was estimated, and the strains were characterized by morphological, biochemical, and molecular methods. Of the 47 strains tested, 10 caused mortality above 85% and showed mean lethal concentrations between 1.05E+7 and 1.54E+8 spores mL-1. The lowest LC50values were obtained for the HD-1 standard strain and the BR145, BR83, BR52, and BR09 strains. The protein profile showed the presence of Cry proteins of 60, 65, 70, 80, and 130 kDa. The molecular characterization showed the presence of cry1, cry2, cry3, and cry11 genes. The morphological analysis identified three different crystalline inclusions: bipyramidal, round, and cuboidal. The cry1 and cry2 genes were the most frequent among the B. thuringiensis strains evaluated and encode Cry proteins toxic to insects of the order Lepidoptera, which agree with the toxicity results obtained by the selective bioassays against E. aurantiana. The results showed four different B. thuringiensis strains toxic to E. aurantiana at the same level as the HD-1 standard strain, and these strains have biotechnological potential for E. aurantiana control through the production of transgenic plants or the formulation of biopesticides.
authors.affiliation: Centro de Ciências Agrárias, Departamento de Agronomia, Univ Estadual de Londrina, Rodovia Celso Garcia Cid, Km 445, CEP 86047-902, Londrina, PR, Brazil. jzorzetti@hotmail.com.
authors.forename: J
authors.identifier: http://orcid.org/0000-0002-1858-7263
authors.initials: J
authors.lastname: Zorzetti
authors.affiliation: Centro de Ciências Biológicas, Departamento de Biologia Molecular, Univ Estadual de Londrina, Rodovia Celso Garcia Cid, Km 445, CEP 86047-902, Londrina, PR, Brazil.
authors.forename: A P S
authors.initials: AP
authors.lastname: Ricietto
authors.affiliation: Centro de Ciências Biológicas, Departamento de Biologia Molecular, Univ Estadual de Londrina, Rodovia Celso Garcia Cid, Km 445, CEP 86047-902, Londrina, PR, Brazil.
authors.forename: F A P
authors.initials: FA
authors.lastname: Fazion
authors.affiliation: Instituto Agronômico do Paraná, Londrina, PR, Brazil.
authors.forename: A M
authors.initials: AM
authors.lastname: Meneguim
authors.affiliation: Centro de Ciências Agrárias, Departamento de Agronomia, Univ Estadual de Londrina, Rodovia Celso Garcia Cid, Km 445, CEP 86047-902, Londrina, PR, Brazil.
authors.forename: P M O J
authors.initials: PM
authors.lastname: Neves
authors.affiliation: Centro de Ciências Biológicas, Departamento de Biologia Molecular, Univ Estadual de Londrina, Rodovia Celso Garcia Cid, Km 445, CEP 86047-902, Londrina, PR, Brazil.
authors.forename: L A
authors.initials: LA
authors.lastname: Vilas-Boas
authors.affiliation: Instituto Agronômico do Paraná, Londrina, PR, Brazil.
authors.forename: R B
authors.initials: RB
authors.lastname: Rodrigues
authors.affiliation: Centro de Ciências Biológicas, Departamento de Biologia Molecular, Univ Estadual de Londrina, Rodovia Celso Garcia Cid, Km 445, CEP 86047-902, Londrina, PR, Brazil.
authors.forename: G T
authors.initials: GT
authors.lastname: Vilas-Bôas
mesh_terms: D000818:Animals; D001406:Bacillaceae; D001413:Bacillus thuringiensis; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; D007915:Lepidoptera; D010572:Pest Control, Biological
chemical_list: D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins
keywords: Citrus; biological control; citrus fruit borer; cry genes; lethal concentration