Broad-leaved weed

Diphenyl ethers are both systemic and contact herbicides and are used for the selective control of annual broad-leaved weeds and grasses in a variety of crops (such as soybeans, maize, rice, wheat, barley, peanuts, cotton, onions and ornamental trees) under different application scenarios. This class of herbicides contains a diphenyl ether moiety as the core substructure. Acifluorfen, bifnox, chlomethoxyfen, chlorni-trofen, fluoroglycofen-ethyl and fomesafen, etc., are representative compounds of the diphenyl ether herbicides (Figure 1). 

Use pattern Orbencarb is a systemic pre-emergence herbicide to control most annual grasses and broad-leaved weeds... 

Pyrithiobac-sodium is a pre- and post-emergence herbicide to control broad-leaved weed and grasses The residue definition is for the parent, pyrithiobac-sodium, only. 

Stable to acid and base in the pH range 3-8. Thenylchlor is a chloroacetamide herbicide for the preemergence and post-planting control of annual grass and broad-leaved weeds in paddy rice The residue definition is for the parent, thenylchlor, only... 

Fluthiacet-methyl is a selective contact herbicide for the post-emergence control of broad-leaved weeds in corn and soybeans. 

Weeds vary from low and succulent broad-leaved weeds that grow best in wet shady areas and the hardier coarse types that are found in drier, more exposed soils, to vines that clamber over coffee trees and smother them with injurious growth, to useless woody bushes that come up between the coffee trees, and tough grasses that compete for both moisture and soil nutrients. In Kenya and Brazil it is essential... 

MCPA Acid 94-74-6 2.51 1950 Herbicide A herbicide for control of annual and perennial broad-leaved weeds... 

Mecoprop Acid 7085-19-0 2.29 -1956 Herbicide A postemergence herbicide used to control broad-leaved weeds such as cleavers, chickweed, plantains, and clover... 

Chlortoluron Phenylurea 15545-48-9 2.79 1994 Herbicide A contact and residual urea herbicide used to control broad-leaved weeds and grasses... 

Isoproturon Phenylurea 34123-59-6 2.07 Unknown Herbicide A herbicide for use, typically, in cereals to control annual grasses and many broad-leaved weeds... 

A preemergence herbicide used for general weed control including grasses and broad-leaved weeds in a range of crops Chemical transformation product. Parent simazine and atrazine Chemical transformation product. Parent atrazine... 

A herbicide to control grass and broad-leaved weeds in a variety of situations including forestry and for control sUme-forming algae, fungi, and bacteria in nonagricultural situations... 

The findings of Crafts and Reiber (4) were somewhat inconsistent with the above conclusions. After sulfonation, gasoline and the low-boiling fraction of stove oil were still toxic to broad-leaved weeds and grasses. The unsulfonatable residue of the heavier fraction of stove oil, boiling between 424 and 570 F., was not toxic. 

The revolution in selective weed control came about in the early 1940s with the discovery of the hormone herbicides 2,4-D and MCPA (see Section 3.3 on Auxin-type herbicides). These compounds were truly selective and very active. They controlled broad-leaved weeds in cereal crops when applied post-emergence. 

The conversion of fatty acids into very long chain fatty acids is specifically inhibited by the thiocarbamate herbicides such as EPTC and triallate (Figure 2.19). These compounds are used pre-plant incorporated for the control of grass and some small seeded broad-leaved weeds in crops such as maize and small grain cereals. 

The move into continuous cereal production and away from mixed farming with firm rotations meant that farmers could cultivate high value crops on all available land without the need for fallow. This could not have been achieved without the use of chemical herbicides. The movement of people from the land to the urban environment during the industrial revolution and thereafter reduced the available labour for hand weeding and weed control became a real problem for the farmer. The revolution was the introduction of 2,4-D and MCPA that allowed broad-leaved weeds to be controlled selectively in the previously dirty cereal crops. 

Both compounds are rapidly translocated herbicides that selectively kill broad-leaved weeds. They mimic the natural auxin, indol-3-ylacetic acid, which is responsible for promoting cell elongation and hence cause unrestrained growth. This uses up all the available nutrients, leading to the death of the plant. A review of the pyridinecarboxylic acids has been published (B-75MI10702). 

Sulfonylurea . Sulfonylurea herbicides are a relatively new class of herbicides generally used for selective pre- and post-emergence control of broad leaved weeds in croplands. Sulfomcturon—methyl is used for broad-spec (ruin selective or nonsclcciive weed control in noncroplands. 

Herbicides. The use of herbicides (qv) based on iodine compounds has its main market in Western Europe. In Canada and the United States these compounds are used only to a small extent. The only significant iodine-containing herbicide is ioxynil [1689-85 4] (4,-hydroxy-3,5,-diiodobenzoic acid). This compound, often used in combination with other herbicides, is formulated for controlling many annual broad-leaved weeds, especially black-bindweed, knotgrass, mayweeds, and com marigold post-emergence in wheat, barley, oats, rye, and triticale (142). Annual consumption of iodine in relation to ioxynils is considered to be about 300—500 t (66). 

Wheat for postemergence control of grass weeds especially Avena fatua and Setaria viridis and some broad-leaved weeds... 

Used alone and in combination with trifluralin or metolachlor for control of broad-leaved weeds and grasses in Soyabeans, field peas, maize... 

Post-emergence control Soil. DTJ0 2-18 days neither florasulam of broad-leaved weeds nor its degradates should leach both roots especially Galium... 

Soil applied control of Animals. Metabolized primarily by broad-leaved weeds in dealkylation of the ethoxy group and... 

Control of problem broad leaved weeds including Xanthium strumarium, Chenopodium album, Ambrosia artemisifolia, Datura stramonium, Amarnthus sp.,... 

Post-emergence control of annual broad-leaved weeds especially Galium aparine, Lamium sp. and Veronica sp. in winter and spring small grain cereals... 

Post-emergence control of broad-leaved weeds e.g., Abutilon theophrasti, Chenopodium album, Amaranthus retroflexus, Xanthium strumarium in maize and soyabeans... 

Selective herbicide with broad spectrum grass control and control of some broad leaved weeds in maize, soybeans, sunflower, wheat, rice... 

Pre-emergence control of annual grass and some broad-leaved weeds in tree fruit,... 

Pre- or early post-emergence herbicides to control annual grasses and broad-leaved weeds 111, 3512... 

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