CS270586B2 - Agent for nitrification prevention - Google Patents

Abstract

1. Nitrification-inhibiting agent, characterised in that it consists of a) dicyandiamide and b) guanylthiourea and/or ammonium thiosulphate, as well as possibly c) ammonium phosphate.

Description

The invention relates to an agent for preventing nitrification of ammonia nitrogen, in particular in mineral and organic fertilizers in soil.

It is known that ammoniacal nitrogen is converted into nitrate nitrogen relatively quickly by bacteria. This nitrification process is influenced by temperature, soil moisture, pH and soil biological activity.

Since nitrate nitrogen, unlike ammoniacal nitrogen, does not adhere firmly to soil particles, it can be very easily washed out of the soil by rain, especially on light, permeable soils. In this way, nitrogen as an important nutrient for plants is lost. In contrast, nitrate levels in groundwater and drinking water may increase, leading to hygiene problems.

In addition to scavenging, nitrate nitrogen is also lost in gaseous form by denitrification of nitrate nitrogen.

By adding a nitrification inhibiting agent, nitrogen losses can be reduced and the utilization of the above-mentioned nitrogen-containing fertilizers can be improved.

A number of nitrification inhibiting agents have been developed for this purpose, for example based on pyridine or aniline, chlorine or sulfur derivatives.

However, these compounds have various disadvantages in practice, such as high volatility, so they need to be incorporated into the soil. In addition, these substances are generally toxic and / or leave toxic residues in the soil. From the ecological point of view, therefore, only those nitrification inhibiting substances that are non-toxic and at the same time do not leave unacceptable residues are usable. Nitrogen compounds, for example dicyandiamide, guanilthiourea or ammonium ammonium sulphate, are particularly useful, these substances completely disintegrate in the soil into nitrogenous substances directly usable by plants. A disadvantage of these compounds, for example, compared to the pyridine derivatives, is their low or too short activity. These substances need to be used in relatively large quantities, so that not only a number of financial problems arise, but also a number of technical problems in their use.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a nitrification inhibiting agent free of the disadvantages of the known compositions, with high efficiency and ease of application, without toxicity or toxic residues.

This object is achieved according to the invention by a nitrification inhibiting agent consisting of 20 to 80% by weight of dicyandiamide and 20 to 80% by weight of guanylthiourea and / or ammonium thiosulphate and / or ammonium phosphate.

Unexpectedly, the composition of the invention has been shown to provide substantially more intensive and longer lasting nitrification inhibitions than the separate administration of the individual components, the effect being greater than the sum of the effects of the individual components.

This synergistic effect, which is strongly expressed also when using a combination of a plurality of individual components, could not be expected.

The nitrification preventing agent consists of dicyandiamide and at least one other component selected from guanylthiourea, ammonium thiosulfate and ammonium phosphate, so that the agent may contain two to four components.

The ratio of the individual components may vary within a wide range, with the synergistic effect less or more expressed.

In the case of the two-component system, mixtures consisting of 20 to 80% by weight of dicyandiamide and 20 to 80% by weight of guanylthiourea are preferred.

CS 270 586 82

Particularly preferred as a three-component system are mixtures consisting of up to 70% by weight of dicyandiamide up to 70% by weight of ammonium thiosulfate and up to 60% by weight of ammonium phosphate.

Furthermore, the composition of the invention may be used as a four-component system, the latter

system I p preferably consists of 20 May to 60 % % by weight dicyandiamide 20 May to 60 % % by weight guanylthiourea. 10 to 50 o, i % by weight ammonium thiosulphate and 10 to 50 % % by weight ammonium phosphate

In the context of the invention, ammonium phosphate is understood to mean compounds of the phosphate type containing ammonium groups, in particular ammonium dihydrogen phosphate, ammonium hydrogen phosphate and ammonium polyphosphate.

The nitrification inhibiting agent according to the invention can be applied as such or also in combination with nitrogen fertilizers.

When used without fertilizer, the amount is in the range of 0.1 to 300 kg / ha, preferably 1 to 60 kg / ha, which can be applied before, simultaneously with or after fertilization.

When the composition according to the invention is applied in combination with a nitrogen fertilizer, the nitrification of which is to be prevented, it is preferably used in an amount of 70 to 99.9, in particular 85 to 99% by weight, based on the weight of the fertilizer, for example urea.

Both mineral and organic fertilizers are suitable as nitrogen fertilizers, and in the case of mineral nitrogen fertilizers all ammonium salts, for example ammonium nitrate or sulphate and ammonia or urea can be used singly or in any desired mixtures. Organic fertilizers include slurry, slurry or slurry.

The composition according to the invention is easy to use and without problems. The composition is suitable for use with solid and liquid fertilizers.

When used with solid fertilizer, the composition of the invention is added to the fertilizer in a conventional manner and mixed with the fertilizer in a conventional plant, for example it is granulated or compressed with it. There are also no problems when added to capillary fertilizers in the form of a solution or suspension. The composition can be added directly in the production of fertilizer in the form of a solution or suspension or additionally. The composition according to the invention is particularly well suited for the production of an aqueous suspension which can be sprayed. In this case, the composition can be applied concurrently with the plant treatment compositions against pests.

The nitrification inhibiting agent according to the invention makes it possible to substantially reduce the amount of fertilizer at the same efficiency or duration of action. Since all components have low toxicity and do not leave any toxic residues in the soil, the proposed composition of the invention is very suitable for practical use.

The following examples illustrate the practical use of the composition of the invention.

CS 270 586 B2

Example 1

100 g of soil (sand with clay, pH 7.2) with 200 mg of nitrogen in the form of urea are mixed with the following amount of active substances:

Experiment 1 = 1.5 mg dicyandiamide (OCD).

experiment 2 - 1.5 mg guanylthiourea (GTH) experiment 3 = 1.5 mg DCD + 1.5 mg GTH. .

In the control experiment, urea was added to the soil in equal amounts but without any active ingredient. The soil was incubated in 0.5 liter plastic bottles at 60% water content and 20 ° C. After 8, 12 and 16 weeks under these conditions the nitrate nitrogen content in the soils was determined and thus the percentage of nitrification was calculated according to the following formula:

a - bi nitrification inhibition in% = - ² --- = --- x 100 a - c where a = nitrate nitrogen content и of control b = nitrate nitrogen content in the experiment c = nitrate nitrogen content in soil.

Outbreaks and disability in% weeks 12 weeks 16 weeks

pukli !. 1: 1.5 mg DCD 21 5 AT try 2: 1.5 mg GIH 60 45 17 : 111 i i: i i i (1) 11 2 Ol 50 17 try 3 i 1,5 mg DCD - ♦ 1.5 mg GTH 8Θ 72 51

Co-administration of dicyandiamide and guanylthiourea resulted in a higher inhibition of nitrification by 7, 22 and 34% higher than the sum of the effects of the individual components.

Example 2

The experiment of Example 1 was repeated, but ammonium sulfate was used as the nitrogen source.

Results:

inhibition in%

Θ weeks 12 weeks 16 weeks

try 1 : 1,5 mg DCD 23 10 0 try 2 • i, mg GTH 50 30 13  11 »(i Γ; r 11 I · 1 ok (lil no 1 1 č 2 73 4 0 13 try 3 : 1,5 mg DCD 1 1.9 mg GIH 02 / 66 4 4

CS 270 586 B2

Obviously, the concomitant use of dicyandiamide and guanylthiourea resulted in a 9, 18 and 31% higher nitrification inhibition than the individual components.

Example 3

A number of experiments were performed according to Example 2, but different combinations of dicyandiamide and guanylthiourea were used. After incubation for 12 weeks, the inhibition of nitrification exceeded the sum of the effects of the individual components by the following percentage:

0.5 mg DCD + 2.5 mg GTH = 17 % 1.0 mg DCD + 2,0 mg GTH = 21 % 1.5 mg CDC + 1.5 GTH = 22 % 2,0 mg DCD ♦ 1.0 mg GTH = 25 % 2.5 mg DCD 0.5 mg GTH = 20 %

Example 4

The procedure of Example 1 was repeated except that ammonium thiosulfate (ATS) was used as the second component. The incubation time was 4, 6 and 8 weeks.

Results:

inhibition in%

4 weeks 6 weeks 8 weeks experiment 1 : 1.5 mg DCD 50 36 21 experiment 2 ; 1.5 mg ATS 12 6 2 sum of experiments 1 and 2 62 42 23 pokus 3 + : 1.5 mg CDC 1.5 mg ATS 65 50 38 Yippee obvious that when co-administered dicyandiamide and ammonium thiosulfate was achieved inhibitions nitrification, higher by 3, 8 and 15 % compared to the sum of the results when administered

individual substances.

Example 5

The experiment of Example 1 was repeated, but a combination consisting of dicyandiamide (DCD), guanylthiourea (GTH) and ammonium thiosulfate (TS) was used. The incubation time was 8, 12 or 16 weeks.

Results:

’· Rana inhibition in% weeks 12 weeks 16 weeks

Experiment 1: 1.0 mg DCD 15 Dec 2 0 Experiment 2: 1.0 mg GTH 41 23 6 Experiment 3: 1.0 mg ATS 2 0 0 sum of experiments 1, 2 and 3 58 25 ’ 8 Experiment 4: 1.0 mg DCD + 1.0 mg GTH + 1.0 mg ATS 77 60 48

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Obviously, by using a combination of dicyandiamide, guanylthiourea and ammonium sulfate, a nitrification inhibition was achieved which was 19. 35 and 40% higher than the sum of the efficacy of the individual components.

Example 6

The experiment of Example 1 was repeated using various combinations of ammonium polyphosphate (APP) in the form of a NP (10:34) solution with the above active ingredients. The incubation time was 4 weeks in experiments 1 and 2 and 12 weeks in experiments 3 and 4.

Results:

Experiment 1:

1.5 mg OCO ♦

1.5 mg ATS trial 2:

1.5 mg OCD +

1.5 mg ATS trial 3:

1.0 mg OCD +

1.0 mg GTH +

1.0 mg ATS trial 4:

1.0 mg OCD +

1.0 mg GTH +

1.0 mg ATS without APP = 66% barrier with APP = 75% barrier without APP = 60% barrier with APP = 73% barrier.

Obviously, the addition of ammonium polyphosphate increased nitrification inhibition by 9 or

%. ·

Example 7 kg of soil was placed in a Mitscherlich vessel in which the effect of a mixture of dicyandiamide (DCO) and guanylthiourea (GTH) active ingredients on the elution of nitrates after urea fertilization was monitored. During the first three weeks after fertilization, the following percentages of urea were eluted.

Urea without active substance 48.2 urea with 10% OCD-N 19.9 urea with 10% GTH-N 14.2 urea with 5% DCD-Nl ♦ 5% GTH-N 10.3

CS 270 586 B2

Example 8

In a field trial, the effectiveness of a combination of dicyandiamide (DCD), guanylthiourea (GTH) and ammonium thiosulfate (ATS) on the yield of diabetes was studied. The active compound combination was applied together with an ammonium nitrate and urea (AHL) solution at a rate of 200 kg / ha of nitrogen, including nitrogen in the active ingredients. The mixture was applied before sowing sugar beet.

The following yields were achieved:

fertilization Yield

dt / ha O AHL without active substance 714 100.0 AHL with 10% DCD-N 730 102.3 AHL with 6% DCD-N + 4% ATS-N 751 105.2 AHL with 4% OCO-N + 2% GTH-N + 4% ATS-N 766 107.3.

OBJECT OF THE INVENTION

Claims (6)

An agent for preventing nitrification, characterized in that it comprises: (a) 20 to 80% by weight of dicyandiamide; and b) 20 to 80% by weight of guanylthiourea and / or ammonium thiosulfate and / or ammonium phosphate. 2. A reagent as claimed in claim 1 comprising 20 to 80% by weight of dicyandiamide and 20 to 80% by weight of guanylthiourea. 3. The reagent of claim 1, wherein the reagent comprises: 20 to 70% by weight of dicyanamide, 20 to 70% by weight of ammonium thiosulfate; 10 to 60% by weight of ammonium phosphate. 4. The reagent of claim 1, comprising: 20 to 60% by weight of dicyandiamide, 20 to 60% by weight of guanylthiourea, 10 to 50% by weight of ammonium thiosulfate; and 10 to 50% by weight of ammonium phosphate. 5. A reagent as claimed in any one of claims 1 to 4, wherein the ammonium phosphate is ammonium polyphosphate. 6. Reagent according to claim 1, characterized in that it contains 70 to 99.9% by weight, preferably 85 to 99% by weight, of a nitrogenous fertilizer such as urea.