USE OF 1,9-DECANEDIOL IN RETARDING UREA HYDROLYSIS

Abstract

A use of 1,9-decanediol in retarding urea hydrolysis in soil is provided. It is found that 1,9-decanediol has a dual regulatory effect, which can not only inhibit the nitrification process, but also retard urea hydrolysis and reduce the transformation of urea to other nitrogen forms. As a fat-soluble root exudate, 1,9-decanediol has high stability in soil, is not easy to be leached away, and causes less environmental pollution. It further broadens an application field of 1,9-decanediol and improves an industrial value of 1,9-decanediol.

Claims

1. A use of 1,9-decanediol, comprising: preparing a mixed solution based on the 1,9-decanediol and urea; and applying the mixed solution to soil containing urease, and the 1,9-decanediol of the mixed solution acting as an inhibitor of the urease to reduce a conversion of the urea to an ammonia nitrogen and thereby retard in retarding urea hydrolysis in the soil.

2. (canceled)

3. The use according to claim 1, wherein an addition amount of the 1,9-decanediol in the soil is in a range of 500 micrograms per kilogram (mg/kg) to 1000 mg/kg.

4-6. (canceled)

Description

DETAILED DESCRIPTION OF EMBODIMENTS

[0012] Embodiment 1: 1,9-decanediol and urea are prepared into a mixed solution to be applied to soil, in which an addition amount of 1,9-decanediol in soil is 100 micrograms per kilogram (mg/kg).

[0013] Embodiment 2: 1,9-decanediol and urea are prepared into another mixed solution to be applied to soil, in which an addition amount of 1,9-decanediol in soil is 200 mg/kg.

[0014] Embodiment 3: 1,9-decanediol and urea are prepared into still another mixed solution to be applied to soil, in which an addition amount of 1,9-decanediol in soil is 500 mg/kg.

[0015] Embodiment 4: 1,9-decanediol and urea are prepared into even still another mixed solution to be applied to the soil, in which an addition amount of 1,9-decanediol in soil is 1000 mg/kg.

TEST EXAMPLE

[0016] 1. Experimental Design

[0017] 1.1 experimental soil: the type of experimental soil is paddy soil, and the texture is sandy loam soil. It is collected from 0-20 cm topsoil of experimental field in Yingtan City, Jiangxi Province (28° 15′N, 116° 55′E). It is sieved by 2 millimeters (mm), mixed, and reserved. The basic physical and chemical properties are shown in Table 1.

[0018] 1.2 test reagent: 1,9-decanediol is customized in market, and a structural formula thereof is C.sub.10H.sub.22O.sub.2. Nitrification inhibitor is dicyandiamide (DCD, a structural formula thereof is C.sub.2H.sub.4N.sub.4) is purchased from Sigma.

[0019] 1.3 experimental treatment: experimental setting as follows: urea treatment (U); nitrification inhibitor DCD +urea treatment including: DCD-20 mg/kg soil; 1,9-decanediol+urea treatment in the soil including: 1,9-D-100 mg/kg, 1,9-D-200 mg/kg, 1,9-D-500 mg/kg, and 1,9-D-1000 mg/kg. Each treatment is repeated three times. The amount of nitrogen applied is 200 micrograms nitrogen per kilogram soil.

[0020] 2. Experimental Procedures

[0021] After the experimental soil is weighed into 100 milliliters (mL) plastic pipe, distilled water is evenly added, and the soil water content is adjusted to 60% of the maximum field water capacity. Then the plastic pipe is sealed with sealing film and uniform holes are pricked to keep air flowing, and pre-cultured in a 25° C. incubator for three days.

[0022] After the pre-culture, according to the different experimental treatments, the corresponding urea and inhibitors (1,9-decanediol and DCD) are weighed to form a mixed solution, the mixed solution is evenly applied to soil, then distilled water is added to maintain a flooded state, and cultured at 25° C. in the field. The contents of urea nitrogen and ammonia nitrogen in soil are measured on the 1.sup.st, 2.sup.nd, 3.sup.rd, 5.sup.th, and 7.sup.th days of culture to evaluate the effects of different inhibitors on nitrogen transformation.

[0023] 3. Experimental Results

[0024] Application of 1,9-decanediol can retard the hydrolysis efficiency of urea, improve the retention time of urea in soil, reduce the conversion of urea to ammonia nitrogen, and retard the time when ammonia nitrogen reaches the peak (see Table 2). DCD has no effect on retarding the hydrolysis efficiency of urea. The efficiencies of retarding urea hydrolysis from large to small is 1, 9-D-1000>1, 9-D-500>1, 9-D-200>1, 9-D-100>DCD.

[0025] With the increase of the addition amount of 1,9-decanediol, the efficiency of retarding urea hydrolysis is more obvious. The addition of 1,9-decanediol 500 mg/kg and 1,9-decanediol 1000 mg/kg can significantly inhibit the urea hydrolysis during the culture period.

TABLE-US-00001 TABLE 1 Physical and chemical properties of soil Total nitrogen NH.sub.4.sup.+—N NO.sub.3.sup.−—N Organic matter pH (g/kg) (mg/kg) (mg/kg) (g/kg) 5.06 0.92 9.94 7.49 16.6

TABLE-US-00002 TABLE 2 contents of ammonia nitrogen and urea nitrogen in soil Nitrogen Treatment forms 1 d 2 d 3 d 5 d 7 d U NH.sub.4.sup.+-N 157.6 ± 1.7b 208.6 ± 3.6a  205.8 ± 3.4a 216.3 ± 4.5a 228.7 ± 5.9a Urea-N  7.9 ± 0.9c  4.9 ± 0.2c   3.5 ± 0.7d    3 ± 0.2c  2.3 ± 0c DCD NH.sub.4.sup.+-N 176.9 ± 5.5a 183.6 ± 4b  203.1 ± 1.6ab 208.4 ± 1.6b 217.9 ± 4.3b Urea-N  4.5 ± 0.4c  1.6 ± 0.3d   1.4 ± 0.2e  1.2 ± 0.1d  2.9 ± 0.4bc 1,9-D-100 NH.sub.4.sup.+-N 171.9 ± 8.1a 176.8 ± 1.2c  197.7 ± 7.3ab 187.3 ± 8.5d 221.7 ± 2.4ab Urea-N  10.1 ± 0.7c  3.7 ± 1.2cd   3.4 ± 0.5d  3.3 ± 0.2c  2.9 ± 0.5bc 1,9-D-200 NH.sub.4.sup.+-N 150.8 ± 2.8b 173.7 ± 1.9c    195 ± 9b 213.9 ± 3.3ab 221.4 ± 4.4ab Urea-N  15.2 ± 0.1c  9.1 ± 0.51b  5.5. ± 1.0c  2.8 ± 0.5c  4.2 ± 1.4ab 1,9-D-500 NH.sub.4.sup.+-N   51 ± 1.1c 160.2 ± 6.2d  180.8 ± 6.3c 207.3 ± 2.1b 217.3 ± 3.3b Urea-N 115.6 ± 13b  11.7 ± 0.4b   10.5 ± 0.7b  6.1 ± 0.6a  3.4 ± 0.7bc 1,9-D-1000 NH.sub.4.sup.+-N  46.3 ± 2.1c  92.9 ± 0.4e    152 ± 1.4d 196.7 ± 2c 203.2 ± 7c Urea-N   139 ± 7.2a  73.4 ± 3.8a   14.8 ± 1.7a    5 ± 0.5b  5.4 ± 0.5a