DD275451A1 - MEANS OF INHIBITING NITRIFICATION - Google Patents

Abstract

The invention relates to agents for inhibiting the nitrification of ammonium nitrogen in Kultursoeden. As active ingredients, the agents contain, in addition to customary auxiliaries and tracer substances, substituted cyanimidodithiocarbonates. The compositions according to the invention can be used in the form of concentrates alone or in admixture with solid or liquid mineral or organic fertilizers. The application rate can be between 0.2 to 200 kg / ha of active ingredient.

Description

Characteristic of the known technical solutions

For the inhibition of the ongoing in the ground microwave conversion processes of ammonium nitrogen in nitrate nitrogen nitrification inhibitors are increasingly used. This ensures effective use of nitrogen while preventing nitrate accumulation in the plant and nitrate leaching into the groundwater. The utilization of the fertilizer nitrogen can be significantly improved by the inhibition or regulation of nitrification and thus the economic benefits of nitrogen fertilization can be increased. The use of the previously known effective nitrification inhibitors is carried out mainly by fertilizer-independent application or bound to solid fertilizers together with these.

Nitrification inhibiting effects have been known and suggested for use in agriculture by a variety of heterocyclic compounds as well as substituted anilines, acetophenones, dichloralurea and other compounds.

Thus, for example, in patent specifications DD-PS 217206 substituted anilines, DD-PS 217693 halogenated acetophenones, DD-PS 229396substituierte 1,2,4-thiadiazole derivatives and in DD-PS107664 the 3,5-dimethyltetrahydro-1,3,5- Thiadiazin-2-thione (Dazomet) described as nitrification-inhibiting agents. In addition, nitrification inhibitory effects of some pyridine, pyrimidine, triazole and pyrazole derivatives are known (U.S. Patent 3,494,757, U.S. Patent 3,635,690, DD Patent 133088, Japanese Patent No. 7247182 and Japanese Patent No. 7247183).

However, these previously known nitrification inhibitors have certain disadvantages, such. B. high volatility, easy leaching, too fast hydrolytic decomposition to inactive fission products, high toxicity, elaborate production processes and the like. On, which preclude an economic application.

Object of the invention

The object of the invention is to inhibit the microbial conversion processes of the ammonium nitrogen into nitrate nitrogen taking place in the soil by means of suitable active ingredients and thus to ensure an effective use of nitrogen for plant growth.

Explanation of the essence of the invention

The object of the invention is to find a nitrification inhibitor which can be prepared in a simple manner and has a good residual action, which enables a surface application.

This object is achieved in that the means for inhibiting the nitrification of ammonium nitrogen in culture soils in addition to conventional excipients and carriers as active compounds of the general formula

ClCH ₀ S ^

^ ^ C = N - C s N, RS

in which R is a lower alkyl or alkenyl radical.

The new active compounds can be prepared by literature methods by alkylation of potassium monoester salts of Cyanimidodithiokohlensäure with Chlorbrom methane (DD-PS 256693).

The compositions of the invention may be in the form of a solid or liquid concentrate z. B. in water or in admixture with a solid, ground or granulated carrier or in admixture with solid and / or liquid mineral or organic fertilizers containing urea and / or ammonia and / or ammonium nitrogen, are used.

The compositions according to the invention are expediently applied shortly before, simultaneously with or shortly after the application of the fertilizer at an application rate of 0.2 to 200 kg / ha of active ingredient, preferably 0.5 to 60 kg / ha. When used with a solid or liquid fertilizer, they can be used with from 0.1% to 50% by weight of the fertilizer nitrogen.

Exemplary embodiments

The compositions according to the invention were added as urea / active substance mixture to a black earth-like sandy loam soil and mixed uniformly with it. The concentration was 16 ppm (based on soil mass) with a nitrogen input of 20 mg N / 100 g soil. After wetting the soil to 50% of the maximum water capacity, it was incubated at 20 ° C for 28 days and then the nitrate or nitrite nitrogen formed was determined. The same urea addition to the bottom served as control as in the test variants. The calculation of the inhibitory effect in% was carried out according to the formula

 · 100% inhibition a -c

a = Nitrite and nitrate content of the control - Nitrite and nitrate content of the samples containing the active substance nitrite and nitrate content of the soil used

The results are summarized in the table below. table Inhibition of nitrification of ammonium nitrogen by the agents according to the invention after 28 days

Active substance R % Inhibition (Invention) 1 CH ₃ CH ₂ 99 2 CH ₃ (CH ₂ ), 97 3 (CHj) ₂ CH 90 4 CH ₂ CHCH ₂ 55 (known) Dichloralharnstoff 31 dazomet 18 N-chloroacetyl, N- (2'-cyanoethyl) -4-chloroaniline 11 3,4-dichloro-chloroacetophenone 21 3-chloroacetylamino-5-methylthio-1,2,4-thiadiazol 64

From the table it can be seen that the inhibition of nitrification of ammonium nitrogen by the agents according to the invention is much better in relation to the comparison products.

Claims (1)

An agent for inhibiting the nitrification of ammonium nitrogen in cultivated soils, characterized in that, in addition to customary excipients and carriers, as active compounds, compounds of the general formula RS
in which R is a lower alkyl or alkenyl radical. Field of application of the invention The invention relates to agents for inhibiting the nitrification of ammonium nitrogen, in particular from mineral and organic fertilizers, in cultivated soils.