Plant resistance to glyphosate has been reported far less frequently than resistance to sulfonylurea and imidazolinone herbicides. However, these studies tend to be anecdotal, without side by side comparisons for a single species or natural isolate. In this study, we tested the frequencies of resistance of three herbicides in a controlled ethylmethanesulfonate (EMS) saturation mutagenesis exper...

Chlorsulfuron (CS) is a potent sulfonylurea herbicide inhibiting specifically acetohydroxyacid synthase which catalyzes the first step in the biosynthesis of branched-chain amino acids in plant cells, bacteria and yeast. The peptide portion of some ergot alkaloids contain inter alia branchedchain amino acids. The influence of CS on growth and alkaloid formation in Claviceps was studied. In an e...

The protective effect of herbicide safener R-28725 and chiral 3-dichloroacetyl oxazolidine safeners in reducing the phytotoxicity of chlorsulfuron to maize were studied by physiological and biochemical tests. The results showed that R-28725 and compound A [(R)-3-dichloroacetyl-2,2-dimethyl-4-ethyl-1,3-oxazolidine] could improve the GSH content, GST activity (in vivo and in vitro), ALS activity ...

To study the possibility of gene rescue in plants by direct gene transfer we chose the Arabidopsis mutant GH50 as a source of donor DNA. GH50 is tolerant of chlorsulfuron, a herbicide of the sulfonylurea class. Tobacco protoplasts were cotransfected with genomic DNA and the plasmid pHP23 which confers kanamycin resistance. A high frequency of cointegration of the plasmid and the genomic DNA was...

Single amino acid substitutions at either of two crucial positions in acetolactate synthase (ALS) result in a chlorsulfuron-insensitive form of this enzyme and, as a consequence, a herbicide-resistant phenotype. Here, we describe the successful in vivo targeting of endogenous tobacco (Nicotiana tabacum) ALS genes using chimeric RNA/DNA and all-DNA oligonucleotides at two different locations. Si...

A series of novel sulfonylurea benzothiazolines was designed by splicing active groups and bioisosterism. A solvent-free synthetic route was developed for the sulfonylurea benzothiazoline derivatives via the cyclization and carbamylation. All compounds were characterized by IR, ¹H-NMR, 13C-NMR, HRMS. The biological activity tests indicated the compounds could protect maize against the injury ca...

Although tremendous progress has been made in recent years in identifying molecular mechanisms of small interfering RNA (siRNA) functions in higher plants, the possibility of direct interaction between genomic DNA and siRNA remains an enigma. Such an interaction was proposed in the 'RNA cache' hypothesis, in which a mutant allele is restored based on template-directed gene conversion. To test t...

Italian ryegrass [Lolium perenne ssp. multiflorum (Lam.)] is a problematic C3 annual weed in winter wheat and other crops the US, continental Europe. The objective of this research was to assess expression profiles herbicide target-site genes upon treatment with field rates ALS- (e.g., chlorsulfuron), PSII- atrazine), EPSPS- glyphosate), HPPD- mesotrione) inhibitors, respectively ryegrass. Furt...

Treatment of field pennycress (Thiaspi arvense L.) leaves with the herbicide chlorsulfuron resulted in a decrease in the export of assimilate. Twelve hours after a spot application of 1 microgram, assimilate translocation was 70% of that in control leaves. In excised leaves treated with chlorsulfuron the total amounts of sugars and free amino acids were 150 and 170%, respectively, of the amount...