02297naa a2200313 a 450000100080000000500110000800800410001902400420006010000220010224500860012426000090021052013840021965000140160365000300161765000160164765000140166365000240167765300320170165300140173365300200174765300220176765300220178970000230181170000190183470000230185370000250187670000210190177300610192221625842024-05-10       2024    bl uuuu     u00u1 u    #d7 ahttp://doi.org/10.1111/jen.132302DOI1 aNASCIMENTO, T. A.  aBacillus thuringiensis strains to control Noctuidae pests.h[electronic resource]  c2024  aThis study aimed to select and characterize Bacillus thuringiensis strains with toxic activity on Helicoverpa armigera, Spodoptera cosmioides and Spodoptera eridania. Fifty B. thuringiensis (Bt) strains were used in selective bioassays for high mortality on H. armigera, and the four most efficient strains were tested on S. cosmioides and S. eridania. Twelve Bt strains were characterized by PCR to detect some cry, cyt and vip genes. Bioassays were also performed to detect the production of beta-exotoxins. Strain 237 caused a mortality rate of 95.6% due to beta-exotoxins. Strains 1368, 1521, 1814 and 3299 showed toxic activity on S. eridania. However, no strain was effective on S. cosmioides. The presence of beta-exotoxin was detected only in strain 237. The molecular characterization of the strains using specific cry, cyt and vip primers showed a great genetic diversity among the 12 strains that showed some mortality on H. armigera and S. eridania. Our results showed that detecting beta-exotoxin in Bt strains is important as it is toxic to insects and vertebrates and persistent in the environment. Strains 1368, 1521, 1814 and 3299 did not show toxicity to H. armigera, while they were toxic to S. eridania and did not produce beta-exotoxin. These strains may be useful for new formulations of biopesticides as well as for cloning and expression of plants' genes.  aBioassays  aEntomopathogenic bacteria  aLepidoptera  aBactéria  aControle Microbiano  aBactéria entomopatogênica  aBioensaio  aGene inseticida  aInsecticidal gene  aMicrobial control1 aCARVALHO, K. S. de1 aMARTINS, D. C.1 aOLIVEIRA, C. R. de1 aQUEIROZ, M. M. de C.1 aVALICENTE, F. H.  tJournal of Applied Entomologygv. 148, p. 371-381, 2024.