Genetic variability of Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) populations from Latin America is associated with variations in susceptibility to Bacillus thuringiensis cry toxins.
Bacillus thuringiensis strains isolated from Latin American soil samples that showed toxicity against three Spodoptera frugiperda populations from different geographical areas (Mexico, Colombia, and Brazil) were characterized on the basis of their insecticidal activity, crystal morphology, sodium dodecyl sulfate-polyacrylamide gel electrophoresis of parasporal crystals, plasmid profiles, and cry gene content. We found that the different S. frugiperda populations display different susceptibilities to the selected B. thuringiensis strains and also to pure preparations of Cry1B, Cry1C, and Cry1D toxins. Binding assays performed with pure toxin demonstrated that the differences in the toxin binding capacities of these insect populations correlated with the observed differences in susceptibility to the three Cry toxins analyzed. Finally, the genetic variability of the three insect populations was analyzed by random amplification of polymorphic DNA-PCR, which showed significant genetic diversity among the three S. frugiperda populations analyzed. The data presented here show that the genetic variability of S. frugiperda populations should be carefully considered in the development of insect pest control strategies, including the deployment of genetically modified maize in different geographical regions.
Monnerat
Rose
R
EMBRAPA--Recursos Genéticos e Biotecnologia, W5 Norte Final, CP 02372, CEP-70.770.970 Brasília, Federal District, Brasil.
Martins
Erica
E
Queiroz
Paulo
P
Ordúz
Sergio
S
Jaramillo
Gabriela
G
Benintende
Graciela
G
Cozzi
Jorge
J
Real
M Dolores
MD
Martinez-Ramirez
Amparo
A
Rausell
Carolina
C
Cerón
Jairo
J
Ibarra
Jorge E
JE
Del Rincon-Castro
M Cristina
MC
Espinoza
Ana M
AM
Meza-Basso
Luis
L
Cabrera
Lizbeth
L
Sánchez
Jorge
J
Soberon
Mario
M
Bravo
Alejandra
A
D000818:Animals; D001413:Bacillus thuringiensis / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D001427:Bacterial Toxins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D004731:Endotoxins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D014644:Genetic Variation; D006460:Hemolysin Proteins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D007843:Latin America; D008871:Microvilli / Q000378:metabolism; D010572:Pest Control, Biological; D016133:Polymerase Chain Reaction; D019105:Random Amplified Polymorphic DNA Technique; D012988:Soil Microbiology; D018411:Spodoptera / Q000145:classification / Q000187:drug effects* / Q000235:genetics* / Q000254:growth & development
D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004731:Endotoxins; D006460:Hemolysin Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis