Glufosinate ammonium

Bialaphos, produced by fermentation of S. hjgroscopicus is sold in Japan. Racemic phosphinothricin [53369-07-6] C H22N04P, produced chemically (304,305), is sold in the United States and elsewhere as the monoammonium salt called glufosinate-ammonium [77182-82-2] C H22N04P H N, or Total or Basta (formerly Hoe 661, Hoe 39866). 

DL-Form monoammonium salt, CjHlSN204P, glufosinate-ammonium, Hoe 661, Hoe 9966, Basra, Total Sol in water. LD,o in male, female mice, male, female rats (mg/kg) 431, 416, 2000, 1620 orally (Langeliiddeke). 

Novel herbicide tolerance to a number of broad-spectrum herbicides, including bro-moxynil, glyphosate, glufosinate ammonium, imidolozinones, and triazines, has been added to new rapeseed and double-low rapeseed (canola) cultivars developed and released in Canada in recent years (McVetty and Zelmer 2007). These herbicide... 

In 1984 the ammonium salt of the compound was introduced to the market under the common name glufosinate-ammonium as a post-emergent herbicide for direded spray application in vineyards. In the following years the label was extended for using glufosinate-ammonium in orchards and plantation crops and subsequently further uses were developed [19]. 

More than 50% of the active ingredient that can penetrate into the leaf is taken up within the first 4—6 h after foUar apphcation and more than 90% is taken up within 24 h [37, 38]. Ullrich et al. [39] showed evidence for active uptake of the compound which is mediated by amino acid carriers. As already mentioned, air humidity modulates the uptake. Under conditions that favor rapid symptom development (high temperatures and high light intensity), the translocation of the compound is limited, whereas in plants kept in the dark after apphcation the active ingredient shows a considerable phloem mobility. Under field conditions glufosinate-ammonium is regarded as a contact herbicide with partial phloem mobility [40]. 

Further registered applications of glufosinate-ammonium cover its use as harvest aid [19], especially for pre-harvest leaf and vine desiccation in potatoes [41]. 

Figure 3.11 The biotransformation pathway and metabolites of glufosinate ammonium salt in plant tissues [94],...

Similarily in the case of the herbicide glufosinate-ammonium -a known inhibitor of glutcuoine synthetase (J[ ), - the strong increase of malic acid can possibly be interpreted as a consequence of the blocked pathway frooi glutamic acid to glutamine, which in this case leads to a back up accumulation of the glutamic acid precursor malic acid in the tricarboxylic acid cycle. 

Diquat, carfentrazone-ethyl, rimsulfuron or glufosinate-ammonium will kill most emerged seedling weeds. These chemicals work by contact action. Other residual heibicides (singly or in mixtures) can also be used, e.g. clomazone, linuron, flufenacet, or pendimethalin. Metribuzin is more persistent, but there are varietal restrictions. On organic soils it can be incorporated into the ridge to improve the control of weeds. 

Chemicals are normally applied to destroy the haulm this encourages skin set and reduces the spread of blight to the tubers. The following may be used diquat (but not in dry conditions), carfentrazone-ethyl, pyraflufen-ethyl or glufosinate-ammonium. 

Historically, much of the desiccation on maincrops was carried out using acid but this is no longer allowed. Glufosinate-ammonium is an alternative cleared for use on maincrop ware potatoes and is widely used. Newer developments include the manufacture of large propane tractor-mounted burners which can straddle three beds at a time and have a high work rate. 

Inert ingredients are presumed to have no physical, chemical, or biological activity, but this is not always the case. Pesticide testing, required to register pesticides, is mostly performed with the active ingredient alone, not the complete formulation. Many of the so-called inert ingredients, of which there are currently about 3000 in use [24], are themselves toxic. Eor example, a commercial herbicide that contains glufosinate ammonium (GLA) as its active component and an anionic surfactant, sodium polyoxyethylene alkylether sulfate (AES), decreases blood pressure and alters the heart rates of rats. GLA alone does not affect either parameter, whereas AES alone does [25]. Xylene, used as a solvent in many pesticides, is a known human neurotoxin [26]. 

OP anticholinesterase, but strictly speaking herbicides such as glyphosate and glufosinate-ammonium are OPs. The general formula of anticholinesterase OPs is shown in Figure 10.1 ... 

Herbicide Metabolism and the Residues in Glufosinate-Ammonium (Phosphinothricin)-Tolerant Transgenic Plants Germany 2002 Vol. 1... 

Crop plants made virus resistant trough coat protein gene-mediated protection Genes and their enzymes that confer tolerance to glyphosate herbicide Genes and their enzymes that confer tolerance to phosphinothricin herbicide Herbicide metabolism and the residues in glufosinate-ammonium (phosphinothricin)... 

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