DD229396A1 - MEANS FOR INHIBITION BZW. REGULATION OF NITRIFICATION OF AMMONIUM NITROGEN IN CULTURED BODIES - Google Patents

Abstract

The invention relates to means for inhibiting or regulating the nitrification of ammonium nitrogen in Kultursoeden containing as active ingredients 3,5-disubstituted 1,2,4-thiadiazoles of the general formula and cause a better utilization of the mineral and organic fertilizer nitrogen in the soil.

Description

Agent for inhibiting or controlling the nitrification of ammonium nitrogen in cultivated soils

Field of application of the invention

The invention relates to means for preventing or regulating the nitrification of ammonium nitrogen, in particular from mineral organic fertilizers, in cultivated soils.

Characteristic of the known technical solutions

Amraonium nitrogen is subject in the soil in a relatively short time of microbial conversion via the intermediate of the nitrite nitrogen to nitrate nitrogen. This nitrification process is significantly influenced by the temperature, the soil moisture, the pH and the biological activity of the soil. Nitrate nitrogen, unlike ammonia nitrogen, is not sorbed by the sorption carriers of the soil, clay and humus. The consequence of this is that nitrate nitrogen during the winter half-year and in heavy rainfall or intensive irrigation also during the ~ summer half-year, especially on light soils, the leaching is subject. The leaching losses can average up to 20 % of the fertilizer nitrogen per year

 The leached nitrogen is not just for the ΕΤ

Ι π 7

α η ⁿ : ι ι) 1 ι '0

Nutrition of crops lost, but it also comes to the enrichment of nitrate nitrogen in groundwater. In connection with the drinking water supply, this can lead to damage to health in humans and animals. In addition to the leaching losses occur annually significant gaseous nitrogen losses by denitrification of the nitrate nitrogen. By inhibiting or regulating the nitrification by means of chemicals, the utilization of the fertilizer nitrogen can be decisively improved and thus the economic benefit of nitrogen fertilization can be increased.

It is already known that for these purposes u.a. Dichlorourea, S.S-dimethyltetrahydro-l.SiS-thiadiazine-2-thione (Dazomet), 2-chloro-6-trichloromethylpyridine, pentachlorophenol, 2-amino-4-chloro-6-methylpyrimidine, and other compounds. Furthermore, some thiadiazoles are known as nitrification inhibitors (Dap. PS 69-5827, 73-10177, 73-07054, 72-04964, 71-00247, 69-10131, 72-24389). However, these compounds for inhibiting nitrification have disadvantages such as e.g. too low efficacy, too high toxicity, elaborate production processes or too high volatility, which preclude an economic application.

Too high volatility of the active ingredients restricts the application process very much and allows only introduction into the soil.

Object of the invention

The aim of the invention is to provide active substances for inhibiting or regulating the nitrification of aramid nitrogen in the soil, which do not exhibit these disadvantages, have a sufficient residual action and permit all application processes, in particular surface application.

Explanation of the essence of the invention

Oiese object is achieved in that 3,5-disubstituted 1,2,4-thiadiazoles of general formula I have been developed, which inhibit the nitrification of ammonium nitrogen in culture soils.

NR ₁

In this formula, R.sup.1 represents chlorine, the amino group which may optionally also be substituted by alkylcarbonyl or alkoxycarbonyl radicals, alkyl or alkenylthio groups and R.sup.1 'a mercapto or alkylthio groups which optionally contain halogen, carbonyl groups or aryl radicals or alkyl - or Aralkylsulfonylgruppen.

The compounds according to the invention can be prepared by processes known from the literature, but for the most part have not yet been described in the literature. They can be prepared, for example, by cyclization of potassium alkyl cyanimidodithiocarbonates with sulfuryl chloride (compound 1) or subsequent oxidation (compounds 5 and 6), with chloramine (compound 2) or subsequent acylation (compounds 4 and 21) successive alkylation of salts of 3,5-dimercapto-l, 2,4-thiadiazole (Comp.3 and 18-20) and by reacting the S-chloro-l ^^ - thiadiazol-S-sulfenyl chloride with unsaturated compounds (comp. 8,9,11) or ketones (verbs 7,10,12,14-17).

The compositions of the invention may be used in admixture with or together with solid or liquid mineral or organic fertilizers containing urea and / or ammonia and / or ammonium nitrogen. They can also be in the form of a solid or liquid

Concentrate, e.g. in water or in admixture with a solid, ground or granulated carrier.

The compositions of the invention may also be used in combination with other agrochemicals, e.g. Pesticides and soil improvers and in combination with other agro-technical measures.

The new agents are expediently applied shortly before, simultaneously with or shortly after application of the fertilizers at a rate of 0.2 to 200 kg of active ingredient / ha, preferably 0.5 to .60 kg / ha. When used together with a solid or liquid fertilizer, they can be used with from 0.1 to 50% by weight of the fertilizer nitrogen. They allow a significant improvement in the utilization of fertilizer nitrogen and thus increase the effectiveness of nitrogen fertilization.

embodiments

The following examples serve to illustrate the invention without limiting it.

example 1

The following 3,5-disubstituted 1,2,4-thiadiazoles listed in Table 1 were synthesized and characterized by the usual analytical methods.

Table 1

Drug-No. R. Rp Physical constants

1 Cl SCH ₃ mp 54-56 ⁰ C

2 NH ₂ SCH ₃ mp 158-159 ⁰ C

3 SCH ₃ SH Fp 153-155 ⁰ C

4 NHCOCH ₂ Cl SCH ₃ mp 145-146 ° C

Drug-No. R ₁ Cl ^R 2 Physical constants i 5 Cl SO ₂ CH ₃ Mp 82-84 ⁰ C • Ν mp 150-152 ⁰ C 6 Cl SO ₂ CH ₂ C ₆ H ₅ Mp 126-128 ⁰ C oil 7 Cl SCH ₂ COCH ₃ oil oil 8th Cl SCH ₂ ClCHCN oil 3 ^Ö1 ₂ CH ₃ oil 9 Cl Cl SCH ₂ = CClCH ₂ Cl oil Mp 102-106 ⁰ C 10 11 Cl SCH (CH ₃ ) COCH ₃ SCH ₂ CH ₂ Cl oil Kp ₁ 115 ⁰ C oil 12 SCH (COCH ₃ ) CH (CH ₃ ) ₂ oil Bp 125-29 ⁰ C Cl Mp 117-119 ° C Cl IN THE 13 Cl 14 Cl Cl 15 SCH ₂ -CH = CH ₂ SCH ₂ COC ₆ H ₅ 16 17 SCH ₂ -CH = CH ₂ SCH (C ₆ H ₅ ) COCH SCH (C ₆ H ₅ ) COCH 18 SCH ₂ -CH = CH ₂ SH 19 NHCOOCH ₃ SCH ₃ 20 SC ₂ H ₅ :: 21 SCH ₃ Example 2

The compositions according to the invention were added as a urea active substance to a black earth-like sandy loam soil and uniformly mixed. The concentration is 16 ppm (based on soil mass) at a nitrogen yield of 20 mg, N / 100 g soil. After moistening the soil to 50 % of the maximum water capacity was incubated at 20 ⁰ C for 28 days and then determined nitrate or nitrite nitrogen determined. As a control, the same urea indication served to the bottom as in the test variants.

The calculation of the inhibitory effect in percent was carried out after

a - b a - c

, 100 = % inhibition

a = nitrite and nitrate content of the control b = nitrite and nitrate content of the active substance samples c = nitrite and nitrate content of the soil used

The results are shown in Table 2.

Table 2

Percent inhibition of nitrification after 28 days of incubation

Active substance no. % inhibition

1 81

2 75

3 74

4 64

5 99

6 74

7 87

8 84

9 84

10 76

11 68

12 64

13 95 14 100

15 96

16 83

17 92

18 77

19 79

20 61

21 74

Drug-No. % inhibition

3,5-Dimethyltetrahydro-1,3,5-thiadiazine-2-thione (Dazomet)

18 dichloroaluminum 31

Claims (6)

invention claim 1. An agent for inhibiting the nitrification of Aramonium nitrogen in cultivated soils, characterized in that it contains as active substances one or more compounds of the general formula N r- R ₁ in which R _{1 is} chlorine, the amino group which may optionally be substituted by alkylcarbonyl alkoxycarbonyl radicals, alkyl or alkenylthio groups and R _{2 is} a mercapto or alkylthio groups which optionally contain halogen, carbonyl groups or aryl or hetaryl radicals or aryl or hetarylthio groups and also alkyl or aralkylsulfonyl groups. 2. A nitrification inhibiting agent according to item 1, characterized in that one or more active compounds of the general formula alone or together with solid or liquid mineral or organic fertilizers containing or releasing urea and / or ammonia and / or Araraoniumstickstoff in the form of a solid or liquid concentrate or in admixture with a solid, ground or granulated carrier. 3. Nitrification inhibitors according to item 1 and 2, characterized in that they are used together with other agrochemicals and / or agrotechnical measures. 4. Nitrification inhibiting agent according to item 1, characterized in that before, simultaneously with or after fertilizer application. 5. means for inhibiting the nitrification according to item 1, characterized in that they in an application rate
from 0.2 to 200 kg of active ingredient / ha, preferably 0.5 to 60 kg / ha are applied. 6. Nitrification inhibiting agents according to item 1, characterized in that they are added to the fertilizers in amounts of from 0.1 to 50% by weight of the fertilizer nitrogen.