Confirmation of dicamba-resistant Palmer amaranth in Tennessee

Abstract Palmer amaranth has a long history of evolving resistance to herbicides the point at which it become significant obstacle row crop production. A survey escapes in dicamba-resistant cotton and soybean fields Tennessee was conducted fall 2021 with objective determining whether poor control due environmental phenomena or development dicamba resistance. greenhouse dose-response screen on 15 accessions. Three accessions were identified relative factor between 1.85 2.49, one accession from Lauderdale County found 14.25. The 1 developed higher level than all others evaluated can no longer be effectively controlled using dicamba. escaping location 2019 field preliminary screens would suggest that passed generations. This research documents first findings failures evolution