CS253327B1 - Synergic herbicidal agent - Google Patents

Abstract

The solution concerns a synergistic herbicidal composition containing a mixture of the active ingredients chlortoluron and/or isoproturon and chlorsulfuron. The disadvantage of separate application of preparations containing individual components is a narrow spectrum of effectiveness on weeds, and in the case of a preparation containing only chlorsulfuron, the risk of adverse effects of its residues in the event of an overdose of the preparation. This risk is eliminated by a synergistic herbicidal composition containing reduced amounts of active ingredients while simultaneously broadening the spectrum of effectiveness compared to separate application of the individual components of the preparation, especially on cottongrass and nightshade.

Description

The invention relates to a combined herbicidal preparation intended for the control of weeds in the stands of agricultural crops, especially cereals.

The disadvantage of applying herbicides containing a single active ingredient is usually a narrow and insufficient spectrum of effectiveness on weeds. This disadvantage is eliminated by repeated applications of different preparations or by applying mixtures prepared from them, so-called tank mixes. Their disadvantage is the risks arising from the field preparation of these mixtures, especially the accuracy of dosage, or even the impossibility of preparing the required mixture.

The described disadvantages are eliminated by the final processing of the mixture of active substances into the form of a combined herbicide preparation, which achieves optimal herbicidal effect, ensures safe application of combined active substances in agricultural practice, and limits the number of otherwise necessary interventions.

The biological effects of herbicidally active substances of the general formula I are known

where R1, R2 are: -H, -CH2, OCH2, Cl, including combinations thereof.

Rjc are: -CH2, -H, including combinations thereof.

Herbicidally active substances of the general formula I in application doses of 100 to 5,000 g per hectare of active substance finalized in the form of a mechanically prepared mixture with surfactants, safeners, stabilizers and inert fillers used in the application form and dose act primarily on weeds:

ragwort, chamomile, seaside bird's-foot trefoil, purple loosestrife, hemp, cornflower, blue mustard, field mustard

Apera spica-venti (L.) Matricaria maritina (L.) Stellaria media (L.) Lamium purpureum (L.) Polygonům sp.

Óaleopsis tetrahit (L.) Centaurea cyanus (L.) Sinapsis arvensis (L.)

Furthermore, the biological effects _of herbicidally active substances of the general formula II (II)

Rj, R^ are: -CHj, _-OCH3 including combinations thereof.

Herbicidally active substances of the general formula II in application doses of 1.0 to 40.0 g/ha and active substances finalized in the form of a mechanically prepared mixture with surfactants, thickeners such as carboxymethylcellulose, buffering agents such as sodium bicarbonate and inert fillers such as kaolin, precipitated silica or precipitated foamed carbonate used in the application form and dose act primarily on weeds:

chundelka panicle chamomile

Apera spica-venti (L.) Matricaria sp.

poppy, wolfsbane, primrose, bird's-foot trefoil, frog's-foot trefoil, field hen, shepherd's purse

Papaver rhoseas (L.)

Galium aparine (L.)

Stellaria media (L.)

Thlaspi arvense (L.)

Capsella bursa-pastoris (L.) Med.

The above herbicidally active substances of general formulas I and IX are used in agricultural practice in a number of finalized preparations containing linuron, chlortoluron, isoproturon, metoxuron, chlorsulfuron as active substances, the application doses of which depend on the specific active substance and its concentration in the preparation and the desired herbicidal effect.

The herbicidal efficacy of individual substances on individual weed species depends both on the type of active substance and on the conditions of use of the preparation of a specific formulation. The simultaneous effect on the treated crop and the residual effect of active substances on subsequent crops are significant, especially for substances of general formula III. Therefore, efforts are made to limit these dangers.

The aforementioned disadvantages are eliminated by the synergistic herbicidal composition which is the subject of the invention, the essence of which lies in the fact that it contains as active substances a mixture of urea derivatives of the general formula I

R ₂ are -H; -Cl?

R1 to R4 are -CH2 and sulfonylurea derivatives of general formula II

where Rp _R2 are -H; -Cl;

Rg, Rj are _CH3 ? ^-OCl3 in a weight ratio of 1 to 50 to 0.01 to 0.5.

The described herbicidal effect is achieved with a suitably selected mixture of active substances of general formulas I and II according to the desired effect and the spectrum of weeds, which are combined with surfactants, auxiliaries (thickeners, antiseptic additives), buffering agents and inert fillers. Combined herbicidal preparations of the above composition further allow, by their effects, to limit the number of necessary interventions in the treated crops, eliminate the risks arising from the need to use higher doses of the herbicidally active substance when applied separately in the form of a preparation and the undesirable phytotoxic and residual effects of these substances, especially on sensitive subsequent crops. At the same time, the combined herbicidal preparation eliminates possible risks arising from the preparation of so-called tank mixes of similar composition in the operating conditions of agricultural practice, as well as eliminates the mutual negative effects of the preparations mixed in this way on the tank mix. The combined herbicidal preparation eliminates the risk of overdose of any of the components of the tank mix.

The combined herbicidal preparation according to the invention enables optimal effect with economical use of active ingredients with minimal ecological burden on the treated vegetation and terrain. Examples of embodiments are given to clarify the subject matter of the invention.

Example

A herbicide preparation containing 500 g/kg of the active ingredient chlorotoluron in combination with 7.5 g/kg of the active ingredient chlorsulfuron in the final preparation of a wettable powder formulated with surfactants - calcium lignin sulfonate (Polyfon H) 50 g/kg, alkyl sulfonate (Tinovetin B) 50 g/kg and filler kaolin 392.5 g/kg was applied post-emergence in autumn in winter wheat crops at an application rate corresponding to 1 kg of the preparation per hectare.

Its herbicidal effect has been compared to:

1. Dicuran WP containing 800 g/kg of the active ingredient chlortoluron in the final formulation of a wettable powder at an application rate of 1 kg/ha.

2. a preparation containing 750 g/kg of the active substance chlorsulfuron (GLEAN 75 DF) in the final preparation of dispersible granules at an application rate of 15 g of the preparation/ha.

The preparations were applied under biologically comparable conditions post-emergence in autumn in winter wheat crops.

The following herbicidal effects were achieved:

weed combined herbicide 1 kg/ha (chlortoluron 500 kg/ha, chlorsulfuron 7.5 g/kg) Chlortoluron (800 g/kg) 1.0 kg/ha chlorsulfuron 750 g/kg) 15 g/ha whisker 98% 94% 97% svizel pritula 70% 0% 98 « maritime chamomile 100% 96% 100 « birdhouse froghouse 100% 100% 100% purple earwig 100% 100% 55% poppy 80% 0% 100%

Example 2 Herbicidal preparation containing 675 g/kg of the active substance isoproturon in combination with 7.5 g/kg active ingredients chlorsulfuron in the final preparation of a wettable powder formulated with surfactants lig- calcium ninsulfonate (Polyfon 0) in the amount of 50 g/kg and sodium alkyl sulfonate (Geropon IN) in the amount of 50 g/kg. thickener carboxymethylcellulose in quantity 2 g/kg, solid substance bicarbonate sodium in the amount of 100 g/kg and inert filler precipitated with silica- clear in quantity 115 .5 g/kg was applied post-emergence in the autumn in a stand of winter wheat. The following herbicidal effects were achieved: weed combined herbicide 1 kg/ha (isoproturon 675 g/kg, chlorsulfuron 7.5 g/kg) isoproturon (750 g/kg) 1.0 kg/ha chlorsulfuron (750 g/kg) 15 g/ha whisker 64% 66% 97 » svizel pritula 73% 70% 98 « maritime chamomile 100% 100% 100% birdhouse Žabinec 100% 100% 100% purple earwig 76% 66% 55% violet rolnl 20% 12% 0% poppy 55% 48 « 100%

Claims (1)

OF THE INVENTION A synergistic herbicidal composition, characterized in that it contains, as active substances, a mixture of a urea derivative of the formula I NH-C — N (X) CH wherein are -CH ₃ ; -CH CH, R 1 are -H; Cl; R ₃ , R ₃ are "CH _3" and the sulfonylurea derivative of general formula II ^R 3 R ₂ Sat ₂ NH-C II (II) wherein R ₁ , R ₂ are H; -Cl; R 1, R 2 are -CH ₃ ; -OCH 3 in a weight ratio of 1 to 50 to 0.01 to 0.5.