Herbicide safener

Uses herbicide safener, in combination with clodinafop... 

Uses herbicide, safener, wheat, rye Trade names (AgrEvo)... 

DeRidder, B. P. and Goldsbrough, P. B. (2006) Organ-specific expression of glutathione S-transferases and the efficacy of herbicide safeners in Arabidopsis. Plant Physiol. 140, 167-175. 

The discovery of pinoxaden is complemented by two further key findings leading to the invention of a family of novel and innovative postemergence grass herbicides safener efficacy and adjuvant response. 

Herbicide safeners (also referred to as herbicide antidotes or protectants) fulfill an important role in crop protection. Safeners are chemicals that protect crop plants from unacceptable injury caused by herbicides. Either by placement on the crop seed or by way of a physiological selectivity mechanism, safeners in commercial use do not negatively impact the weed control of the herbicide. Although many herbicides have been developed for use without a safener, some of the strongest and most broad-spectrum herbicides tend towards border-line crop selectivity, which may completely preclude use in a particular crop or at least limit maximum use rates or the crop varieties that can be safely treated. It is for such situations that safeners have been developed. Several books and reviews of safeners have been written over the past 20 years [1-3]. It is not the intention of this chapter to cover in detail older safeners, but rather to focus on more recently developed commercial safeners as well as some of the older compounds still in wide commercial usage. 

The story of herbicide safeners began in 1947 with an accidental observation by Otto Hoffmann, a researcher in the Gulf Oil Company. On entering his greenhouse on a hot summer afternoon he saw that tomato plants had suffered injury that he presumed was from 2,4-D vapor drift. However, plants treated with 2,4,6-trichlorophenoxyacetic acid showed no symptoms of this injury [4]. Hoffmann recognized the potential use of such an effect and started research into compounds that could protect crops from herbicide injury. 

It is usually part of the investigations on the mechanism(s) of safener action to look for possible safener interactions with the herbicide partner at the process of herbicide uptake into the crop. Looking through the relevant literature gives a complex picture. This can also be seen in a review of Davies and Caseley [2], who present an exhaustive compilation of safener effects on herbicide uptake for relevant herbicide/safener combinations developed up to that time. Only in 20% of the cases was the uptake of the herbicide reduced in combination with the... 

This observation, but also contradictory results of other studies, which showed either no effect or a stimulatory effect of N A on herbicide uptake, made it questionable that an interference with herbicide uptake plays a significant role for the mechanism of action of this safener [30, 31). It should be added that contradictory results (inhibition, stimulation or no effect on herbicide uptake) can also be found in the literature for other herbicide/safener combinations. 

From the presented research data herbicide safeners obviously act in crops predominantly by enhancement of herbicide metabolism to non-phytotoxic degradation products. Notably, all safeners investigated so far only influenced the rate of herbicide metabolism, but did not alter the metabolic pathway. Hence safeners never altered the pattern of herbicide metabolites, but only led to quantitative shifts in the ratios between the phytotoxic parent compound and the metabolites of the herbicide, when compared with control plants without safener application. These quantitative differences between plants with and without safener treatment... 

De Ridder BP, Dixon DP, Edwards R, Goldsbrough PB (2002) Inductiini of glutathione S-transferases in Arabidopsis by herbicide safeners. Plant Physiol 130 1497-1505... 

Herbicide Safeners Enhance Herbicide Selectivity by Inducing GSTs and Other Enzymes... 

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