A point mutation in IAA34 confers resistance to the auxin herbicide 2,4-D in Sisymbrium orientale.

ABSTRACT:

Background

Sisymbrium orientale has evolved resistance to 2,4-D in Australia due to a 27 bp deletion in SoIAA2. However, one population of Sisymbrium orientale resistant to 2,4-D (R1) did not contain the SoIAA2_Δ27, suggesting another 2,4-D resistance mechanism was present in this population. Here, we reported a novel target-site resistance mechanism of 2,4-D in the R1 population.

Results

R1 is resistant to 2,4-D, 2-methyl-4-chlorophenoxyacetic acid (MCPA), and fluroxypyr with increased tolerance to dicamba, triclopyr and picloram. The 2,4-D resistance level for R1 is lower than resistant populations containing a 27 bp deletion in IAA2. 2,4-D resistance in R1 was due to a single dominant gene. Pretreatment of R1 with the P450 inhibitor malathion did not reduce resi

SUBMITTER: Qi Y 

PROVIDER: S-EPMC12159386 | biostudies-literature | 2025 Jul

REPOSITORIES: biostudies-literature