Metolachlor plants

Herbicide Glasses and Databases. Herbicides can be classified as selective and nonselective. Selective herbicides, like 2,4-D (2,4-dichlorophenoxyacetic acid), metolachlor [51218-45-2] and EPTC [759-94 ] are more effective against some types of plants than others, eg, broadleaved plants vs grasses. Glyphosate [1071 -83-6] is representative of the nonselective herbicides used for total vegetable control. 

Approximately 3.7 million kg of herbicides and more than 12 800 kg of insecticides were applied to agricultural areas in the Lake Erie Basin in 1995 [15]. Herbicides are applied during spring planting to nearly all corn and soybean fields. Similar to the situation in Ontario, metolachlor and atrazine were... 

Wheat stubble may physically intercept up to half of the atrazine as it is applied (Ghadiri et al., 1984). Subsequent rains wash atrazine off the stubble and bring it into contact with the soil. In Nebraska, suppression of summer annual weeds in wheat stubble was proportional to the amount of stubble. Crutchfield et al. (1985) showed that even though heavier wheat stubble intercepted more metolachlor applied in spring prior to ecofallow com planting and reduced the amount of herbicide actually reaching the soil, weed suppression by the heavier stubble more than offset the interception effect. 

This range of compounds consists of the many chemicals that are used to control pests worldwide. Target species include insect, animal, or plant species. Examples of the hundred or so pesticides that have been studied to determine their removal during drinking water treatment processes include -5-triazines (atrazine, simazine, cyanazine, propazine), lindane, DDT, 2, 4-D, atachlor, metolachlor, asulam, hymexazol, methomyl, imidacloprid, carbaryl, linuron, thiobencarb, and diquat. 

Full-scale plant for the production of rac-metolachlor in operation (capacity > 10000 t/... 

Full-scale plant for production of > 10000 t/y (S)-metolachlor starts operation 2003 Since the start of production >50000 tons of (S)-NAA have been produced without major problems and without the need for further optimization... 

Full-scale plant for production of > lO OOO t/y metolachlor starts operation... 

In addition to efficient application and incorporation the following factors have significantly increased the weed control from EPTC, EPTC + dietholate, or butylate when reduced performance due to enhanced biodegration was observed 1) reduce weed pressure or establish conditions favorable for immediate, uniform weed emergence 2) immediate, uniform incorporation just prior to corn planting 3) tank mixtures of carbamothioate herbicides with atrazine, cyanazine, or metolachlor 4) rotation for one year to no herbicide, alachlor, cycloate, metolachlor, or trifluralin or, 4) formulations of EPTC plus R251005 at 6.7 + 1.1 kg/ha. 

The vacuole, enclosed by the tonoplast membrane, may constitute as much as 90% of the volume of the mature plant cell and can provide a temporary storage site for intermediary metabolites such as organic acids. Substances such as tannins and calcium oxalate appear to be permanently deposited in the vacuole. It also seems to serve as a repository for metabohtes that could be toxic to the plant cell. It has been demonstrated that the glutathione conjugate of metolachlor, a herbicide... 

Henderson KL, Belden JB, Coats JR (2007) Mass balance of metolachlor in a grassed phytoremediation system. Environ Sci Technol 41(ll) 4084-4089 Orchard BJ, Doucette WJ, Chard JK, Bugbee B (2000) A novel laboratory system for determining fate of volatile organic compounds in planted systems. Environ Toxicol Chem 19(4) 888-894... 

Pesticides (aldicarb, carbofuran, isoproturon, chlorotoluron, metolachlor, mecc op, dichlorprop, MCPA, 2,4-D, methoxychlor, TDE, DDT, dieldrin, and DDE) in drinking water Bacterial endotoxins (lipopolysaccharides) in protein complexation Fungicide validamycin A in rice plants... 

Phytotoxic diloroacetamides provided a linear relationship between severe inhibition of growth and inhibition of the incorporation of [ CJoleic acid into VLCFAs in Scenedesmus acutus [7]. In higher plants, the incorporation of [ C] stearic acid or malonyl-CoA into VLCFAs was inhibited by diloroacetamides while the formation of fatty acids up to Cig was not influenced [8]. Acyl elongation with 20 0-CoA and 18 0-CoA primer substrates was inhibited by the active (S)-enantiomer of metolachlor but not by the (R)-isomer [1, 9). Inhibition of VLCFA formation was also observed in metazachlor-resistance mutant (Mz-1) cells of S. acutus [9]. Thus, the phytotoxic action of chloroacetamide herbicides is most likely by the inhibition of VLCFA synthesis. 

Kawahigashi H, Hirose S, Ohkawa H, Ohkawa Y (2006) Phytoremediation of the herbicides atrazine and metolachlor by transgenic rice plants expressing human CYPlAl, CYP2B6, and CYP2C19. J Agric Food Chem 54 2985-2991... 

Figure 2. After 250 days of remediation, artificial soil columns planted with prairie grasses had significantly less retractable metolachlor and pendimethalin as compared with unvegetated soil columns.

Plant selection is crucial. In die studies presented here, some grass species increased dissipation, one grass species had litde observable effect, and mulberry trees may have inhibited metolachlor dissipation. Additionally, as seen in the mulberry experiment, pesticide damage to the plant may reduce plant growth and therefore, the inpact of die plant on the environment. 

Herbicides are used in many different forms. There are herbicides that are active against all herbs, vhile others show herb-selective action. Herbicides can be taken-up by the plant via roots or via leaves. Important chemical classes of herbicides are carbonic acid based, urea based, aniline based, and phosphonic or phosphoric acid based. The aniline-based herbicide (Sj-metolachlor is shown as example in Table 5.3.19. This herbicide is used in corn farming and is one of the most important examples of products industrially synthesized by asymmetric synthesis using a chiral transition metal complex. The asymmetric synthesis was established after it was discovered that almost all the activity (95%) is caused by the (Sj-metolachlor stereoisomer. 

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