摘要:Widespread adoption of MON 87701 × MON 89788 soybean, expressing Cry1Ac
Bt protein and glyphosate tolerance, has been observed in Brazil. A proactive program was implemented to phenotypically and genotypically monitor Cry1Ac resistance in
Chrysodeixis includens (Walker). Recent cases of unexpected injury in MON 87701 × MON 89788 soybean were investigated and a large-scale sampling of larvae on commercial soybean fields was performed to assess the efficacy of this technology and the distribution of lepidopteran pests in Brazil. No significant shift in
C. includens susceptibility to Cry1Ac was observed eight years after commercial introduction of this technology in Brazil. F
2 screen results confirmed that the frequency of Cry1Ac resistance alleles remains low and stable in
C. includens. Unexpected injury caused by
Rachiplusia nu (Guenée) and
Crocidosema aporema (Walsingham) in MON 87701 × MON 89788 soybean was detected during the 2020/21 season, and studies confirmed a genetically based alteration in their susceptibility to Cry1Ac. MON 87701 × MON 89788 soybean remains effective against
Anticarsia gemmatalis (Hübner),
C. includens,
Chloridea virescents (Fabricius) and
Helicoverpa armigera (Hübner) in Brazil. However, there is evidence of field-evolved resistance to MON 87701 × MON 89788 soybean by the secondary soybean pests
R. nu and
C. aporema.