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Phalaris minor (littleseed canary grass) is a major weed in wheat fields in some parts of Iran. Diclofop-methyl, fenoxaprop-P-ethyl, and clodinafop-propargyl are three acetyl coenzyme A carboxylase (ACCase)-inhibiting herbicides that are commonly used to control this grass in wheat fields.Thirty-four P. minor populations with suspected resistance to ACCase-inhibiting herbicides were sampled from wheat fields in the provinces of Fars and Golestan in Iran.The dose-response assays that were conducted under controlled greenhouse conditions indicated that 14 populations were resistant to fenoxaprop-P-ethyl, seven populations were resistant to both fenoxaprop-P-ethyl and diclofop-methyl, and three populations were resistant to fenoxaprop-P-ethyl, diclofop-methyl, and clodinafop-propargyl. These populations showed different levels of resistance to the applied herbicides, compared to the susceptible population. These results suggest that different mechanisms of resistance could be involved. The enzyme assay revealed that the existence of modified ACCase in the three most-resistant populations (AR, MR4, and SR3) is responsible for the resistance of these populations.

Increased foliar activity of clodinafop-propargyl and/or tribenuron-methyl by surfactants and theirsynergistic action on wild oat (Avena ludoviciana) and wild mustard (Sinapis arvensis) wbm_353 292..299Surfactants can improve postemergence herbicide efficacy and reduce the amount of herbicide required to obtain weed control.The effect of surfactants on the efficacy of herbicides is complicated and depends on the interaction among the plant, surfactant, and herbicide.The effects of surfactants on the efficacy of clodinafop-propargyl and/or tribenuron-methyl on wild oat (Avena ludoviciana) and wild mustard (Sinapis arvensis) under greenhouse conditions were investigated. In addition, the surface tension of aqueous solutions of the surfactants and surfactants + herbicides was determined. Significantly lower surface tension values were obtained with the aqueous solutions of citofrigate (Citogate plus Frigate) alone and with the herbicides used in this study.The citofrigate surfactant lead to the greatest enhancement of clodinafop-propargyl and/or tribenuron-methyl efficacy and the effect was species-dependent. The efficacy of clodinafop-propargyl and/or tribenuron-methyl in the presence of surfactants in controlling wild oat was higher than for wild mustard.The foliar activity of the tested herbicides rose with increasing surfactant concentrations.The tank mixture of clodinafop-propargyl and tribenuronmethyl showed a synergistic effect in controlling wild oat and wild mustard. The synergistic effect in controlling wild mustard was greater than for wild oat.

Nowadays, public concern relating to ecological deleterious effects of heavy metals is on the rise. To evaluate the potential of Rapistrum rugosum and Sinapis arvensis in lead- contaminate phytoremediate, a pot culture experiment was conducted. The pots were filled by soil treated with different rates of leadoxide (PbO) including 0 (control), 100, 200, 300, 400, and 500 mg Pb per 1 kg soil. Germinated seeds were sown. Surprisingly, with increasing concentration of Pb, dry weight of R. rugosum and S. arvensis did not decrease significantly. In both of species, the concentration of Pb was higher in roots than shoots. In general, S.arvensis was absorbed more Pb compared to R. rugosum. The results revealed high potential of R. rugosum and S. arvensis in withdrawing Pb from contaminated soil. For both species, a positive linear relation was observed between Pb concentration in soil and roots. However, linear relationship was not observed between Pb concentration in the soil and shoots. Although both species test had low ability in translocation Pb from roots to shoots but they showed high ability in uptake soil Pb by roots. Apparently, these plants are proper species for using in phytoremediation technology.