TM3-3e
International Starch Institute · Technical Memorandum
Potato Juice as Fertilizer
Three-year field investigation, September 1988 – September 1991 · Sandy soil, Jutland, Denmark
Original English report reproduced below. Numerical tables are preserved in their source layout and can be scrolled horizontally on small screens. Figures are listed by their original captions; image files were not included in the supplied text.
Introduction
Potato and tapioca starch is produced from fresh raw materials with a high content of juice. The extraction of starch also releases the juice. The juice is recycled to the fields and this technical memorandum describes the effect of utilizing the juice from potatoes as a fertilizer.
The Danish starch industry processes more than half of the domestic potato crop. Production of potato starch has multiplied during the membership of the EEC, and so has the outlet of potato juice. Accordingly, the utilization of the valuable nutrients in potato juice is of great concern.
Potatoes contain approx. 70% of juice with approximately 5% of dry matter - half of which is sugars and protein bringing about 30,000 ppm BOD5 in the concentrated juice. Being a natural product variations occur. The juice also contains potassium and magnesium and a typical analysis of fruit juice is:
Constituents of the potato juice:
- Nitrogen, N 4,300 ppm equivalent to 26,875 ppm protein
- Phosphorus, P 490 ppm
- Potassium, K 4,900 ppm
- Magnesium, Mg 260 ppm
- Dry substance 5.1 %
These nutrients are all valuable fertilizers. Exactly how valuable and exactly what will happen when used according to good agricultural practice, were the questions to be answered by a 3- year study starting September 1988 and ending September 1991. In this study potato fruit juice was applied on grass and black uncropped soil in the autumn and spring in different quantities.
Summary and Conclusion
The effect of manuring with potato juice on sandy soil has been studied during a three-year test period.
All three winters were mild and with a considerable nitrogen mineralization throughout the winter. The adverse effect is to some degree compensated for by the better growing conditions of grass, which has proved quite efficient in absorbing the minerals released.
Potato juice applied in the autumn to black fields gave high losses of nitrogen during the winter due to nitrogen leaching.
Use of potato juice equivalent to 100 kg nitrogen per ha on grass in the autumn does not give any significant leaching of nitrogen during the winter. The utilization of nitrogen the following growing season is therefore as high as 70-80%. Potato juice equivalent to 150 kg N/ha increases leaching significantly and the utilization decreas¬es correspondingly.
By application in spring just prior to sowing, utilization of nitrogen in potato juice of 80-85% is expected.
Kvælstoftab kan begrænses ved kilden
Allerede i 1988–1991 undersøgte International Starch Institute, hvordan udvaskning af kvælstof fra kartoffelfrugtsaft kunne begrænses gennem dyrkningspraksis.
Ved udbringning af kartoffelfrugtsaft svarende til 100 kg N/ha i november blev følgende gennemsnitlige årlige nitratudvaskning målt:
| Med rajgræs som efterafgrøde | 10,2 kg N/ha |
| Uden plantedække om vinteren | 91,2 kg N/ha |
Forskel: 81 kg N/ha årligt – svarende til næsten 89 % mindre udvaskning. Allerede for snart 40 år arbejdede vi med at mindske tabet af kvælstof ved kilden, før det nåede grundvand og vandløb.
Kilde: International Starch Institute, markforsøg 1988–1991, tabel 10. Udvaskningen er beregnet ud fra målte nitratkoncentrationer og modelleret nedsivning.
Method
The experiment was divided in 16 treatments, each with 4 repetitions as follows:
---------------------------------------------------------------- A. GREEN B. BLACK (Catch crop: None) Catch crop: Rye grass Round-Up used to remove vege¬ta¬tion. ----------------------------------------------------------------- 1. Basic manuring 1. 100 N KFS, NOV. 2. 50 N KFS, SEP 2. 100 N KFS+inhibitor, NOV 3. 100 N KFS, SEP 3. 50 N HG, spring 4. 50 N KFS, NOV 4. 100 N HG, spring 5. 100 N KFS, NOV 5. 100 N KFS, spring 6. 150 N KFS, NOV 7. 50 N HG, spring 8. 100 N HG, spring 9. 50 N KFS, spring 10. 100 N KFS, spring 11. 150 N KFS, spring ----------------------------------------------------------------- Basic = Basic dressing with P, K + N (30 kg/ha N) H in spring HG = Artificial fertilizer N = Total nitrogen, kg/ha KFS = Potato juice undiluted Inhibitor= Nitrification inhibitor The experiment took place on sandy soil in Jutland, Denmark. All 64 plots had spring barley in all three years. The straw is removed after harvest and the outgrown plots are harvested in the autumn. 20 plots planned without vegetation through out the winter are then sprayed down with Round-Up. In spring all plots are ploughed. In summer time the plots are irrigated when needed. For each plot the yields of dry matter, nitrogen and potassium content in grain, straw and stubble are measured. Dry matter and nitrogen content of grass is determined by sampling after harvest, in November and again before ploughing in spring. The leaching of nitrogen and potassium is calculated on the basis of analysis of soil water taken out at a depth of 80 cm, combined with model calculations of the percolation in the same depth. The soil water is sampled by vacuum. A tube with a ceramic cup at the lower end and a rubber stopper at the top is put under vacuum. Each test plot is provided with two sampling tubes. That means a total of 8 samplings per treatment. The two samples from each plot are mixed to a joint sample for that plot. On average, sampling is done every second week. Each soil water sample is analyzed for nitrate. Potassium and ammonium is analyzed monthly. The soil water analysis is supplemented with analysis of soil samples taken 0-25, 25-50 and 50-75 cm below soil surface before the outbringing of juice in September, November and March. 4 - 5 samples are taken from each plot and mixed, which means 17 - 20 samples per treatment. Before starting the trial, soil samples have been analyzed for pH, potassium (K), phosphor (P) and total nitrogen (N), total organic carbon C and texture. In the experiment period each soil sample is analyzed for nitrate + ammonium (Nmin) and potassium. At the end of the test total nitrogen and total organic carbon have been measured. Before the start of the test four soil profiles have been described. In each profile 18 cores of undisturbed soil (volume = 100 cm3) - five from a depth of 10 and 37 cm, four samples from a depth of 52 and 77 cm - were sampled for retention analysis. From the retention analysis the root zone capacity for plant available water were calculated. The calculations of actual evaporation/transpiration and percolation are performed on the basis of climate data obtained from a nearby weather station. Only rainfall is measured directly on the test area. For the calculations the Evacrop water balance model is used. The leaching is calculated by multiply¬ing the percolation with the average concentration between two sampling dates. The soil is coarse sandy and classified as JB no 1 in the Danish classification system. The analysis of texture is shown in table 1. There is a tendency towards forming of hard pan in part of the area, which has been grubbed (broken) earlier. The underground is somewhere graveled. Climate The average temperature and rainfall are shown in figure 2. Table 5 gives the water balance for the 3 years of test calculat¬ed from 1st of September to the 31st of August and figure 5 shows the calculated amounts of percolation. In figure 1 the retention curve is shown. The retention curves show the relation between the logarithms and the suction in cm (pF) and the water content of the soil gives thereby an impression of the ability to retain water. In table 2 dry volume weight, porosity and the water capacity calculated from the retention curves are shown. The volume weight and the porosity are normal for the soil type. With an estimated efficient depth of the plant roots of 60 cm the root zone capacity for plant available water is 72 cm. In the area with hard pan the efficient depth of the plant roots is estimated to be less than 60 cm. There is a compensation - the soil in this area will be expected to retain a little more water at field capacity, which will compensate for a minor depth of the roots. In table 3 the results of chemical analysis of soil samples taken at the start of the September 1988 are shown. pH and phosphor content P is normal, while potassium K and magnesium Mg are low. The carbon content of the soil in relation to organic bound nitrogen, C/N, is rather high, which means that a tendency towards immobilization of nitrogen is to be expected. The outbringing of potato juice (PJ). A Hardi field sprayer is used for the outbringing of the potato juice. The pump yields 150 to 160 litres per minute with a pressure of 2.5 bar. On a 5 m long spraying boom 19 nozzles are mounted. Before and after each application of potato juice the yield of the spray equipment was monitored. The speed of the tractor was adjusted so each passing of a plot gave exactly 50 kg of nitrogen per ha. The speed was stopwatch-monitored and the amount of potato juice was also monitored by collecting fruit juice in four trays placed on each plot during passing. The figures obtained are shown in table 4. The stopwatch method is well in agreement with the method of collecting juice in trays, except for one treatment in November 1989 where heavy wind drift may have compromised the sampling. The outbringing has been based on estimated values for nitrogen content, which in 1989 gave some disagreement between the two methods. Plots not fertilized with fruit juice and plots fertilized with only 50 and 100 kg of nitrogen per ha as fruit juice had received supplementary potassium and phosphor as PK-fertilizer. Nitrogen was given in the form of calcium-ammonium-nitrate (KAS). The actual quantities of nitrogen and potassium per plot are given in table A5 to A12. Abbreviations KFS Potato juice undiluted KFS+ Potato juice with nitrification inhibitor (Didin) added HG Artificial fertilizer KAS Calcium Ammonium Nitrate (Kalkammonsalpeter)
N Nitrogen
K Potassium
P Phosphorous
C Carbon
LSD Least significant difference
SEP September
NOV November
MAR Marts
N-balance=Ntil - Nopt + Nmin(start) - Nmin(end)
Ntil Nitrogen added as KFS or HG. Nitrogen from other sources (app. 20 N kg/ha) rainfall, irrigation etc. is not included in balance calculations
Nopt Nitrogen retained in grain and stubble
Nudv Nitrogen washed out
Nmin Nitrogen inorganic (mineralized)
UDL Barley with undersown rye grass
Table 1. Texture analysis, per cent of dry soil
-----------------------------------------------------------------
Depth Humus Clay Silt Fine Coarse Gravel/
Org. sand sand stone
cm matter <0.002 <0.02 <0.2 <2 mm >2 mm
-----------------------------------------------------------------
0-25 3.2 3.9 3.1 23.2 62.7 4.0
25-50 1.4 3.2 1.7 22.2 64.8 6.8
50-75 0.5 2.6 0.9 20.3 68.5 7.3
-----------------------------------------------------------------
Table 2. Soil volume weight, porosity and water capacity
-------------------------------------------------------------------
Depth Volume- Porosity Field Plant in- Plant
weight capacity available available
pF = 2.0 water water
pF = 4.2
cm g/cm3 % mm mm mm
-------------------------------------------------------------------
0-25 1.47 43.4 48.2 11.0 37.2
25-45 1.53 41.9 26.2 5.3 20.9
45-60 1.48 43.9 16.2 2.6 13.6
60-100 1.56 41.1 47.6 4.4 43.2
0-60 - - 91 19 72*
0-100 - - 138 23 115
--------------------------------------------------------------------
* Root zone capacity
Table 3. Chemical soil analysis.
-----------------------------------------------------------------
Depth pH P K Mg Total-C Total N C/N
cm water ** mg/100g soil ** % %
-----------------------------------------------------------------
0-25 6.5 4.3 4.3 1.7 1.90 0.092 20.7
25-50 5.9 1.1 2.4 0.7 0.89 0.035 25.5
50-75 5.9 0.2 1.4 0.3 0.31 0.013 24.8
**** kg/ha ***** ***** ton/ha ****
0-25 - 158 158 62 69.8 3.38 -
25-50 - 42 92 27 34.0 1.34 -
50-75 - 8 53 11 11.8 0.49 -
0- 75 - 208 303 100 115.6 5.21 22.2
-----------------------------------------------------------------
Table 4. Quantity of potato juice applied in one-pass
----------------------------------------------------------------------
Date ***** Measured **** N- N- K- K-
in trays stopwatch content applied content applied
ton/ha ton/ha kg/ton kg/ha kg/ton kg/ha
----------------------------------------------------------------------
20.09.1988 13.1 13.1 3.9 51 5.1 67
16.11.1988 13.5 13.4 3.6 48 4.6 62
14.03.1989 14.5 14.2 3.4 48 3.9 55
13.09.1989 13.7 13.9 5.3 73 5.4 75
15.11.1989 11.8 14.0 4.7 66 4.9 69
21.03.1990 14.8 14.7 3.4 50 4.4 65
24.09.1990 14.5 13.7 3.7 51 3.6 49
15.11.1990 12.1 11.7 4.3 50 5.0 59
20.03.1991 11.0 11.8 3.8 44 4.3 50
----------------------------------------------------------------------
Table 5. Rainfall, irrigation, evaporation and run off
1. SEP - 31. Aug., 1988-91, mm per year.
------------------------------------------------------------
Year Rainfall Irrigation Evaporation Run off
Precipi. Barley UDL Barley UDL
------------------------------------------------------------
1988/89 797 68 449 466 455 451
1989/90 851 76 455 497 451 420
1990/91 882 17 388 409 541 506
-----------------------------------------------------------------
UDL = Barley with undersown grass.
Table 6. Grain yield of spring barley (85% DS), hkg/ha.
-----------------------------------------------------------------
N-applied Rye grass catch-crop. Uncropped during winter
KFS KFS KFS HG KFS KFS+ KFS HG
Time: SEP NOV MAR MAR NOV NOV MAR MAR
-----------------------------------------------------------------
1989:
Basic dressing 27.0 27.0 27.0 27.0 - - - -
+ 50 N 35.7 38.0 33.6 33.0 - - - 30.4
+100 N 43.3 44.7 41.6 41.6 24.0 25.2 38.4 37.5
+150 N - 47.3 45.8 - - - - -
LSD (95%) ******* 3.8 ******** ********2.4*******
1990:
Basic dressing 34.7 34.7 34.7 34.7 - - - -
+ 50 N 40.5* 43.8* 43.9 48.2 - - - 47.5
+100 N 46.9* 49.3* 53.7 58.6 33.1 34.7 51.0 55.2
+150 N - 51.0* 61.2 - - - - -
LSD (95%) ******* 2.7 ******** ******** 2.2 *******
1991:
Basic dressing 23.8 23.8 23.8 23.8 - - - -
+ 50 N 30.6 30.8 29.5 32.7 - - - 22.0
+100 N 33.9 34.4 34.8 38.9 15.1 16.4 23.9 25.9
+150 N - 35.1 39.4 - - - - -
LSD (95%) ******* 2.7 ******** ******** 2.3 *******
Average 1989-91:
Basic dressing 28.5 28.5 28.5 28.5 - - - -
+ 50 N 36.5 38.5 35.6 37.9 - - - 33.3
+100 N 43.2 43.1 43.4 46.3 24.1 25.4 37.7 39.5
+150 N - 44.5 48.8 - - - - -
LSD (95%) ******* 2.6 ******** ******** 1.1 *******
-----------------------------------------------------------------
*Corrected to yield by nominal N-applied
KFS = Potato juice, KFS+ = Potato juice + nitrification inhibitor,
HG = Artificial fertilizer.
Table 7. Content of nitrogen in rye grass (top + stubble), kg/ha
-------------------------------------------------------------------
1988/89 1989/90 1990/91
Treatment MAR Harvest NOV MAR Harvest NOV MAR
-------------------------------------------------------------------
1. Basic dressing 44 6 23 19 5 16 22
2. 50 N i KFS, SEP 67 - 57 45 5 28 41
3. 100 N i KFS, SEP 103 - 91 66 5 36 60
4. 50 N i KFS, NOV 63 - 26 34 5 22 40
5. 100 N i KFS NOV 76 - 23 33 4 19 46
6. 150 N i KFS NOV 91 - 27 34 4 22 45
8. 100 N i HG, MAR - - - 22 - 16 27
9. 50 N i KFS, MAR - 6 - - - -
10 100 N i KFS, MAR - 6 - 21 7 23 28
11 150 N i KFS, MAR - 7 36 - - -
-------------------------------------------------------------------
Table 8. Nitrogen content in grain + straw.
Average 1989-91, kg/ha.
-------------------------------------------------------------------
N-applied Rye grass catch-crop Uncropped during w¬inter
KFS KFS KFS HG KFS KFS+ KFS HG
Time: SEP NOV MAR MAR SEP NOV MAR MAR
-------------------------------------------------------------------
Basic dressing 38.7 38.7 38.7 38.7 - - - -
+ 50 N 52.8 55.4 51.3 54.0 - - - 49.2
+100 N 68.2 64.9 69.8 73.4 36.1 37.9 60.7 65.3
+150 N - 71.4 89.4 - - - - -
LSD (95%) ******* 3.9 ******** ******** 2.0 *******
-------------------------------------------------------------------
Table 9. Potassium content in grain + straw.
Average 1989-91, kg/ha.
-------------------------------------------------------------------
N-applied Rye grass catch-crop Uncropped during w¬inter
KFS KFS KFS HG KFS KFS+ KFS HG
Time: SEP NOV MAR MAR SEP NOV MAR MAR
-------------------------------------------------------------------
Basic dressing 28.0 28.0 28.0 28.0 - - - -
+ 50 N 38.4 40.7 45.5 39.9 - - - 40.5
+100 N 49.3 46.7 50.9 52.3 30.1 31.3 51.2 49.4
+150 N - 48.5 64.1 - - - - -
LSD (95%) ******** 5.8 ******** ******** 2.8 *******
-------------------------------------------------------------------
Table 10. Leaching of nitrate nitrogen
1. September - 31. August. kg/ha.
--------------------------------------------------------------
N-applied Rye grass catch-crop Uncropped fields
KFS KFS KFS HG KFS KFS+ KFS HG
Time: SEP NOV MAR MAR NOV NOV MAR MAR
--------------------------------------------------------------
1989:
Basic dressing 5,7 5.7 5.7 5.7 - - - -
+ 50 N 6.7 7.5 4.5 4.7 - - - 30.9
+100 N 6.0 8.8 4.1 4.4 98.6 57.0 30.8 30.9
+150 N - 17.5 6.0 - - - - -
LSD (95%) ****** 5.4 ******** ******* 16.7 *******
1990:
Basic dressing 1.7 1.7 1.7 1.7 - - - -
+ 50 N 2.2* 1.5* 1.5 1.5 - - - 29.9
+100 N 5.1* 9.2* 3.4 2.9 84.5 63.6 40.1 36.4
+150 N - 25.3* 1.7 - - - - -
LSD (95%) ******* 8.7 ******** ******** 11.4 ******
1991:
Basic dressing 4.8 4.8 4.8 4.8 - - - -
+ 50 N 7.4 15.3 5.0 7.4 - - - 59.9
+100 N 15.9 12.6 8.3 10.7 90.4 91.4 68.0 57.6
+150 N - 33.9 9.9 - - - - -
LSD (95%) ******* 9.6 ******** ******** 10.3 ******
Ave. 1989-91:
Basic dressing 4.1 4.1 4.1 4.1 - - - -
+ 50 N 5.4 8.1 3.7 4.5 - - - 40.2
+100 N 9.0 10.2 5.3 6.0 91.2 70.7 46.3 41.6
+150 N - 25.6 5.9 - - - - -
LSD (95%) ******* 5.1 ******** ******** 7.5 *******
----------------------------------------------------------------
*Corrected to yield at nominal N-applied
KFS+ = Potato juice with nitrification inhibitor added.
Table 11. Leaching of ammonium-nitrogen
1. September - 31. August. 1988-91. kg/ha per year.
-----------------------------------------------------------------
N-applied Rye grass catch-crop Uncropped during w¬inter
KFS KFS KFS HG KFS KFS+ KFS HG
Time: SEP NOV MAR MAR NOV NOV MAR MAR
-----------------------------------------------------------------
Basic dressing 0.13 0.13 0.13 0.13 - - - -
+ 50 N 0.13 0.24 0.13 0.09 - - - 0.24
+100 N 0.20 0.21 0.37 0.12 1.14 1.84 0.15 0.15
+150 N - 0.28 0.11 - - - - -
LSD (95%) ******* 0.20 ******* ******** 1.08 ******
-----------------------------------------------------------------
Table 12. Mean concentration of ammonium-nitrogen
weighted in relation to the run off. 1988-91, mg/l.
-----------------------------------------------------------------
N-applied Rye grass catch-crop Uncropped during w¬inter
KFS KFS KFS HG KFS KFS+ KFS HG
Time: SEP NOV MAR MAR NOV NOV MAR MAR
-----------------------------------------------------------------
Basic dressing 0.03 0.03 0.03 0.03 - - - -
+ 50 N 0.03 0.05 0.03 0.02 - - - 0.05
+100 N 0.04 0.05 0.08 0.03 0.25 0.39 0.03 0.03
+150 N - 0.06 0.02 - - - - -
-----------------------------------------------------------------
Table 13. Accumulated nitrogen balance, SEP 88 - SEP 91, kg/ha
-----------------------------------------------------------------
N-applied Rye grass catch-crop Uncropped fields
KFS KFS KFS HG KFS KFS+ KFS HG
Time SEP NOV MAR MAR NOV NOV MAR MAR
-----------------------------------------------------------------
Basic dressing -53 -53 -53 -53 - - - -
+50 N 70 36 49 49 - - - -49
+100 N 174 155 125 122 30 97 25 41
+150 N - 234 194 - - - - -
-----------------------------------------------------------------
Table 14. Soil content of total-N at 0 - 25 cm depth
At the end of the trial, SEP 1991, ton/ha.
----------------------------------------------------------------
N-applied Rye grass catch-crop Uncropped fields
KFS KFS KFS HG KFS KFS+ KFS HG
Time SEP NOV MAR MAR NOV NOV MAR MAR
----------------------------------------------------------------
Basic dressing 3.3 3.3 3.3 3.3 - - - -
+50 N 3.5 3.4 3.6 3.7 - - - 3.6
+100 N 3.8 3.5 3.6 3.7 3.2 3.3 3.5 3.3
+150 N - 3.6 3.5 - - - - -
LSD (95%) ****** 0.4 ******* ******* n.s. ******
-----------------------------------------------------------------
Table 15. Leaching of potassium
1. September - 31. August. Kg/ha.
----------------------------------------------------------------
N-applied Rye grass catch-crop Uncropped during w¬inter
KFS KFS KFS HG KFS KFS+ KFS HG
Time: SEP NOV MAR MAR NOV NOV MAR MAR
----------------------------------------------------------------
Basic dressing 35 35 35 35 - - - -
+ 50 N 37 34 31 32 - - - 41
+100 N 40 42 32 31 64 62 39 39
+150 N - 48 31 - - - - -
LSD (95%) ******* 5 ****** ****** 11 *******
----------------------------------------------------------------
Table 16. Mean concentration of potassium,
weighted in relation to run off, 1988-91, mg/l.
----------------------------------------------------------------
N-applied Rye grass catch-crop Uncropped during w¬inter
KFS KFS KFS HG KFS KFS+ KFS HG
Time: SEP NOV MAR MAR NOV NOV MAR MAR
----------------------------------------------------------------
Basic dressing 7.9 7.9 7.9 7.9 - - - -
+ 50 N 8.5 7.6 7.0 7.2 - - - 9.0
+ 100 N 8.9 9.6 7.4 7.1 13.7 13.2 8.6 8.6
+ 150 N - 10.8 7.0 - - - - -
----------------------------------------------------------------
Table A1. Grain and straw yield (85% DS.), hkg/ha.
----------------------------------------------------------------
Treatment Grain Straw
1989 1990 1991 Ave. 1989 1990 1991 Ave.
----------------------------------------------------------------
A: Catch-crop of rye grass
1: Basic dress 27.0 34.7 23.8 28.5 12.3 17.6 10.7 13.5
2: 50 N SEP 35.7 43.1 30.6 36.5 16.5 25.7 16.4 19.5
3: 100 N SEP 43.3 52.5 33.9 43.2 21.4 33.9 19.1 24.8
4: 50 N NOV 38.0 46.7 30.8 38.5 17.8 28.7 14.9 20.4
5: 100 N NOV 44.7 50.3 34.4 43.1 21.8 32.1 19.0 24.3
6: 150 N NOV 47.3 51.0 35.1 44.5 24.2 32.3 20.2 25.6
7: 50 N KAS 33.0 48.2 32.7 37.9 16.5 29.5 14.6 20.2
8: 100 N KAS 41.6 58.6 38.9 46.3 20.4 37.1 21.2 26.2
9: 50 N MAR 33.6 43.9 29.5 35.6 16.4 26.6 14.9 19.3
10 100 N MAR 41.6 53.7 34.8 43.4 21.5 34.5 18.3 24.8
11 150 N MAR 45.8 61.2 39.4 48.8 24.8 41.0 25.7 30.5
LSD (95%) 3.8 2.7 2.7 2.6 2.9 3.5 2.7 2.5
B: Uncropped during winter
1: 100 N NOV 24.0 33.1 15.1 24.1 12.8 21.2 9.9 14.6
2: 100 N NOV+ 25.2 34.7 16.4 25.4 11.7 19.9 9.9 14.0
3: 50 N KAS 30.4 47.5 22.0 33.3 15.5 30.0 14.7 20.1
4: 100 N KAS 37.5 55.2 25.9 39.5 20.2 36.7 16.8 24.6
5: 100 N MAR 38.4 51.0 23.9 37.7 19.9 34.0 18.9 24.3
LSD (95%) 2.4 2.2 2.3 1.1 1.5 2.5 2.9 1.6
----------------------------------------------------------------
KAS = calcium ammonium nitrate
Table A2. Nitrogen content in grain and straw, kg/ha.
----------------------------------------------------------------
Treatment Grain Straw
1989 1990 1991 Ave. 1989 1990 1991 Ave.
----------------------------------------------------------------
A: Catch-crop of rye grass
1: Basic dress 30.4 40.4 28.0 32.9 4.9 7.6 4.8 5.8
2: 50 N SEP 40.7 52.9 39.5 44.4 6.6 11.4 7.2 8.4
3: 100 N SEP 52.0 70.1 47.7 56.6 8.7 17.0 9.0 11.6
4: 50 N NOV 43.4 58.1 38.9 46.8 6.9 12.1 6.9 8.6
5: 100 N NOV 54.0 62.6 46.4 54.3 9.5 13.8 8.4 10.6
6: 150 N NOV 61.8 66.2 50.2 59.4 12.1 14.6 9.4 12.0
7: 50 N KAS 37.1 57.7 41.1 45.3 6.6 13.2 6.2 8.7
8: 100 N KAS 48.6 78.9 55.4 61.0 9.3 17.9 10.1 12.4
9: 50 N MAR 37.9 53.0 37.3 42.7 6.7 12.2 6.8 8.6
10 100 N MAR 50.1 72.1 48.6 57.0 11.2 17.9 9.3 12.8
11 150 N MAR 61.4 92.1 62.5 72.0 14.3 23.7 14.1 17.4
LSD (95%) 4.0 3.9 3.8 3.2 1.4 2.2 1.5 1.2
B: Uncropped during winter
1: 100 N NOV 29.0 39.5 18.4 29.0 5.5 9.5 6.5 7.2
2: 100 N NOV+ 30.4 41.3 20.8 30.9 5.5 8.7 6.6 7.0
3: 50 N KAS 35.5 56.4 27.8 39.9 5.9 12.9 9.1 9.3
4: 100 N KAS 45.9 76.6 37.4 53.3 8.0 17.5 10.3 12.0
5: 100 N MAR 46.8 66.2 32.6 48.5 7.9 16.3 12.3 12.2
LSD (95%) 3.4 3.9 3.2 1.7 1.0 1.4 2.3 0.9
-------------------------------------------------------------------
Table A3. Potassium content in grain and straw, kg/ha.
------------------------------------------------------------------------
Treatment Grain Straw
1989 1990 1991 Ave. 1989 1990 1991 Ave.
------------------------------------------------------------------------
A: Catch-crop of rye grass
1: Basic dress 10.1 17.3 10.6 12.7 8.0 29.5 8.4 15.3
2: 50 N SEP 13.2 21.4 13.1 15.9 10.6 45.2 11.6 22.5
3: 100 N SEP 15.7 25.8 13.9 18.4 14.4 62.4 15.7 30.8
4: 50 N NOV 13.9 22.9 13.2 16.7 11.2 48.7 12.1 24.0
5: 100 N NOV 16.4 25.3 14.3 18.7 15.5 53.8 14.9 28.0
6: 150 N NOV 17.6 25.1 15.6 19.4 18.9 50.3 18.1 29.1
7: 50 N KAS 12.1 22.9 14.1 16.4 9.5 51.1 10.0 23.5
8: 100 N KAS 14.3 28.6 16.2 19.7 11.7 72.2 14.0 32.6
9: 50 N MAR 12.3 21.6 13.2 15.7 9.8 46.7 32.8 29.8
10: 100 N MAR 15.0 26.5 15.1 18.9 15.8 65.3 15.0 32.1
11: 150 N MAR 16.7 29.9 17.3 21.3 20.4 84.3 23.6 42.8
LSD (95%) 1.5 1.9 2.1 1.4 2.7 7.2 18.7 5.9
B: Uncropped during winter
1: 100 N NOV 9.4 16.3 6.8 10.8 9.6 33.3 15.1 19.3
2: 100 N NOV+ 9.6 16.8 7.4 11.3 9.0 32.6 14.2 19.5
3: 50 N KAS 11.0 22.4 9.6 14.3 9.7 48.2 20.5 26.1
4: 100 N KAS 13.2 26.5 11.2 17.0 12.4 66.2 18.6 32.4
5: 100 N MAR 13.9 24.8 11.0 16.6 13.9 60.3 29.7 34.6
LSD (95%) 0.8 1.1 1.1 0.5 1.8 4.0 6.1 2.4
------------------------------------------------------------------------
Table A4. Stubble Yield and N content in stubble. hkg/ha & kg/ha.
------------------------------------------------------------------
Treatment Yield N-content
1989 1990 1991 Ave. 1989 1990 1991 Ave.
------------------------------------------------------------------
A: Catch-crop of rye grass
1: Basic dress. 4.6 10.0 6.0 6.9 2.1 7.3 3.6 4.4
2: 50 N SEP . 10.0 5.9 7.9 . 7.7 3.8 5.7
3: 100 N SEP 6.2 11.0 6.1 7.8 3.2 8.5 4.0 5.2
4: 50 N NOV 5.7 12.7 5.7 8.0 2.8 9.4 3.7 5.3
5: 100 N NOV 5.9 12.7 6.4 8.3 2.9 10.2 4.1 5.7
6: 150 N NOV 7.1 12.5 6.2 8.6 4.1 10.2 4.2 6.2
7: 50 N KAS 5.5 12.6 6.9 8.4 2.6 10.3 4.5 5.8
8: 100 N KAS 7.2 13.2 7.7 9.4 3.8 11.2 5.8 6.9
9: 50 N MAR 5.6 11.0 5.6 7.4 2.5 9.2 3.6 5.1
10 100 N MAR 5.2 14.7 4.9 8.3 2.7 12.3 3.4 6.1
11 150 N MAR 7.5 11.3 6.5 8.4 4.8 11.3 5.0 7.0
LSD (95%) - - 1.8 1.2 - - 1.2 1.1
B: Uncropped during winter
1: 100 N NOV 5.0 9.7 4.9 6.5 2.5 8.7 3.3 4.9
2: 100 N NOV+ . 9.2 4.5 6.9 . 7.3 2.8 5.0
3: 50 N KAS . 14.8 6.8 10.8 . 11.4 4.8 8.1
4: 100 N KAS 6.9 13.2 7.2 9.1 3.9 10.9 5.2 6.7
5: 100 N MAR 7.1 12.8 6.2 8.7 4.2 11.4 4.3 6.6
LSD (95%) - - 1.3 1.5 - - 1.0 1.4
------------------------------------------------------------------
Table A5. Nitrogen balance, SEP 1988 - SEP 1989, kg/ha
--------------------------------------------------------------------
Treatment N N N Nmin Nmin Balance
added retained leached 88 89
--------------------------------------------------------------------
Catch-crop of rye grass:
1A: Basic dress 30 -35 -6 10 -13 -14
2A: 50 N SEP 79 -47 -7 10 -14 22
3A: 100 N SEP 128 -61 -6 10 -22 50
4A: 50 N NOV 79 -50 -8 10 -17 14
5A: 100 N NOV 127 -64 -9 10 -23 42
6A: 150 N NOV 176 -74 -18 10 -28 67
7A: 50 N KAS 80 -44 -5 10 -13 28
8A: 100 N KAS 130 -58 -4 10 -14 64
9A: 50 N MAR 78 -45 -5 10 -15 24
10A 100 N MAR 127 -61 -4 10 -18 53
11A 150 N MAR 175 -76 -6 10 -27 76
LSD (95 %) 4.6 5.4 7.9
Uncropped during winter:
1B: 100 N NOV 137 -35 -99 10 -24 -10
2B: 100 N NOV+ 133 -35 -57 10 -22 29
3B: 50 N KAS 80 -41 -31 10 -23 -5
4B: 100 N KAS 130 -54 -31 10 -24 31
5B: 100 N MAR 127 -55 -31 10 -29 22
LSD (95 %) 3.7 16.7 9.6
-------------------------------------------------------------------
Table A6. Nitrogen balance, SEP 1989 - SEP 1990, kg/ha
--------------------------------------------------------------------
Treatment N N N Nmin Nmin Balance
added retained leached 89 90
--------------------------------------------------------------------
Catch-crop of rye grass:
1A: Basic dress 30 -48 -2 13 -15 -21
2A: 50 N SEP 103 -64 -3 14 -19 30
3A: 100 N SEP 176 -87 -10 22 -24 77
4A: 50 N NOV 96 -70 -4 17 -24 15
5A: 100 N NOV 162 -77 -18 23 -21 70
6A: 150 N NOV 227 -81 -48 28 -24 102
7A: 50 N KAS 80 -71 -2 13 -18 3
8A: 100 N KAS 130 -97 -3 14 -24 21
9A: 50 N MAR 80 -65 -2 15 -18 10
10A 100 N MAR 130 -90 -3 18 -26 29
11A 150 N MAR 180 -116 -2 27 -33 57
LSD (95 %) 5.2 8.7 7.9 5.0
Uncropped during winter:
1B: 100 N NOV 162 -49 -85 24 -31 22
2B: 100 N NOV+ 168 -50 -64 22 -30 47
3B: 50 N KAS 80 -69 -30 23 -30 -26
4B: 100 N KAS 130 -94 -36 24 -29 -4
5B: 100 N MAR 130 -83 -40 29 -35 2
LSD(95 %) 4.5 11.5 9.6 6.3
-------------------------------------------------------------------
Table A7. Nitrogen balance, SEP 1990 - SEP 1991, kg/ha.
--------------------------------------------------------------------
Treatment N N N Nmin Nmin Balance
added retained leached 90 91
--------------------------------------------------------------------
Catch-crop of rye grass:
1A: Basic dress 30 -33 -5 15 -25 -17
2A: 50 N SEP 81 -47 -7 19 -27 19
3A: 100 N SEP 132 -57 -16 24 -35 48
4A: 50 N NOV 80 -46 -15 24 -36 7
5A: 100 N NOV 129 -55 -13 21 -39 43
6A: 150 N NOV 179 -60 -34 24 -43 66
7A: 50 N KAS 80 -47 -7 18 -26 17
8A: 100 N KAS 130 -66 -11 24 -40 38
9A: 50 N MAR 74 -44 -5 18 -28 15
10A 100 N MAR 119 -58 -8 26 -36 42
11A 150 N MAR 163 -77 -10 33 -48 61
LSD (95%) 4.5 9.6 5.0 8.8
Uncropped during winter:
1B: 100 N NOV 129 -25 -90 31 -26 18
2B: 100 N NOV+ 139 -27 -91 30 -27 23
3B: 50 N KAS 80 -37 -60 30 -30 -17
4B: 100 N KAS 130 -48 -58 29 -38 15
5B: 100 N MAR 119 -45 -68 35 -40 0
LSD (95%) 3.7 10.3 6.3 8.9
-------------------------------------------------------------------
Table A8. Accumulated nitrogen balance, SEP 1988 - SEP 1991, kg/ha.
--------------------------------------------------------------------
Treatment N N N Nmin Nmin Balance
added retained leached 88 91
--------------------------------------------------------------------
Catch-crop of rye grass:
1A: Basic dress 90 -116 -12 10 -25 -53
2A: 50 N SEP 263 -158 -17 10 -27 70
3A: 100 N SEP 436 -205 -32 10 -35 174
4A: 50 N NOV 255 -166 -27 10 -36 36
5A: 100 N NOV 418 -195 -39 10 -39 155
6A: 150 N NOV 582 -214 -100 10 -43 235
7A: 50 N KAS 240 -162 -14 10 -26 49
8A: 100 N KAS 390 -220 -18 10 -40 122
9A: 50 N MAR 232 -154 -11 10 -28 49
10A 100 N MAR 376 -209 -16 10 -36 125
11A 150 N MAR 518 -268 -18 10 -48 194
LSD (95%) 12 15 9
Uncropped during winter:
1B: 100 N NOV 428 -108 -274 10 -26 30
2B: 100 N NOV+ 440 -113 -212 10 -27 97
3B: 50 N KAS 240 -148 -121 10 -30 -48
4B: 100 N KAS 390 -196 -125 10 -38 41
5B: 100 N MAR 376 -182 -139 10 -40 25
LSD (95%) 6 22 9
-------------------------------------------------------------------
Table A9. Potassium balance, SEP 1988 - SEP 1989, kg/ha
--------------------------------------------------------------------
Treatment K K K Kmin Kmin Balance
added retained leached 88 89
--------------------------------------------------------------------
Catch-crop of rye grass:
1A: Basic dress 105 -18 -36 303 -321 33
2A: 50 N SEP 138 -24 -36 303 -365 17
3A: 100 N SEP 165 -30 -37 303 -376 26
4A: 50 N NOV 136 -25 -34 303 -333 47
5A: 100 N NOV 160 -32 -42 303 -359 30
6A: 150 N NOV 185 -37 -43 303 -409 0
7A: 50 N KAS 105 -22 -32 303 -321 33
8A: 100 N KAS 105 -26 -36 303 -292 54
9A: 50 N MAR 129 -22 -31 303 -339 40
10A 100 N MAR 148 -31 -37 303 -388 -6
11A 150 N MAR 166 -37 -40 303 -388 4
LSD (95 %) 3.6 9.1 63.2
Uncropped during winter:
1B: 100 N NOV 160 -19 -52 303 -363 29
2B: 100 N NOV+ 163 -19 -48 303 -348 51
3B: 50 N KAS 105 -21 -45 303 -331 11
4B: 100 N KAS 105 -26 -45 303 -288 49
5B: 100 N MAR 148 -28 -42 303 -344 37
LSD (95 %) 1.9 9.0 52.0
--------------------------------------------------------------------
Table A10. Potassium balance, SEP 1989 - SEP 1990, kg/ha
--------------------------------------------------------------------
Treatment K K K Kmin Kmin Balance
added retained leached 89 90
--------------------------------------------------------------------
Catch-crop of rye grass:
1A: Basic dress 105 -47 -34 321 -366 -20
2A: 50 N SEP 149 -67 -36 365 -466 -54
3A: 100 N SEP 187 -88 -33 376 -422 19
4A: 50 N NOV 143 -72 -27 333 -431 -54
5A: 100 N NOV 175 -79 -38 359 -419 -3
6A: 150 N NOV 207 -75 -40 409 -478 23
7A: 50 N KAS 105 -74 -31 321 -318 4
8A: 100 N KAS 105 -101 -28 292 -319 -51
9A: 50 N MAR 139 -68 -29 339 -410 -29
10A 100 N MAR 167 -92 -29 388 -457 -22
11A 150 N MAR 195 -114 -22 388 -491 -44
LSD (95 %) 8.6 8.8 63.2 69.3
Uncropped during winter:
1B: 100 N NOV 175 -50 -61 363 -471 -42
2B: 100 N NOV+ 175 -50 -63 348 -478 -68
3B: 50 N KAS 105 -71 -37 331 -354 -25
4B: 100 N KAS 105 -93 -34 288 -306 -39
5B: 100 N MAR 167 -85 -31 344 -455 -61
LSD (95 %) 4.6 21.3 52.0 38.0
--------------------------------------------------------------------
Table A11. Potassium balance, SEP 1990 - SEP 1991, kg/ha.
--------------------------------------------------------------------
Treatment K K K Kmin Kmin Balance
added retained leached 90 91
--------------------------------------------------------------------
Catch-crop of rye grass:
1A: Basic dress 105 -19 -35 366 -376 41
2A: 50 N SEP 123 -25 -41 466 -429 94
3A: 100 N SEP 135 -30 -49 422 -477 2
4A: 50 N NOV 132 -25 -40 431 -405 94
5A: 100 N NOV 154 -29 -46 419 -479 20
6A: 150 N NOV 176 -34 -61 478 -551 8
7A: 50 N KAS 105 -24 -32 318 -366 0
8A: 100 N KAS 105 -30 -29 319 -352 13
9A: 50 N MAR 124 -46 -32 410 -414 42
10A 100 N MAR 137 -30 -30 457 -456 78
11A 150 N MAR 150 -41 -30 491 -506 64
LSD (95%) 17.9 6.2 69.3 52.1
Uncropped during winter:
1B: 100 N NOV 154 -22 -79 471 -396 127
2B: 100 N NOV+ 154 -22 -73 478 -398 139
3B: 50 N KAS 105 -30 -41 354 -304 84
4B: 100 N KAS 105 -30 -38 306 -265 78
5B: 100 N MAR 137 -41 -45 455 -384 122
LSD (95%) 6.3 9.6 38.0 27.5
--------------------------------------------------------------------
Table A12. Accumulated potassium balance, SEP 88-SEP 91, kg/ha.
--------------------------------------------------------------------
Treatment K K K Kmin Kmin Balance
added retained leached 88 91
--------------------------------------------------------------------
Catch-crop of rye grass:
1A: Basic dress 315 -84 -104 303 -376 54
2A: 50 N SEP 410 -115 -112 303 -429 57
3A: 100 N SEP 487 -148 -119 303 -477 46
4A: 50 N NOV 411 -122 -101 303 -405 86
5A: 100 N NOV 489 -140 -126 303 -479 47
6A: 150 N NOV 568 -146 -144 303 -551 31
7A: 50 N KAS 315 -120 -95 303 -366 37
8A: 100 N KAS 315 -157 -93 303 -352 16
9A: 50 N MAR 392 -136 -92 303 -414 53
10A 100 N MAR 452 -153 -96 303 -456 50
11A 150 N MAR 511 -192 -92 303 -506 24
LSD (95%) 17 12 52
--------------------------------------------------------------------
Uncropped during winter:
1B: 100 N NOV 489 -90 -192 303 -396 113
2B: 100 N NOV+ 492 -90 -185 303 -398 123
3B: 50 N KAS 315 -121 -123 303 -304 70
4B: 100 N KAS 315 -148 -117 303 -265 88
5B: 100 N MAR 452 -154 -118 303 -384 99
LSD (95%) 9 31 28
---------------------------------------------------------------------
Fig. 1 Retention’s curves. Volume-percent water versus pF (log cm water
column) at different depth.
Fig. 2. Average local temperature and rainfall. Temperature in Celsius and
rainfall in mm versus time. The observations are averaged monthly.
Fig. 3 The water contents of the root zone. The water content of the root
zone versus field capacity (surplus/deficit, mm) over time. The crop is
spring barley with ray grass catch crop.
Fig. 4. Grain yields hkg/ha versus quantity of potato juice. The plots have
all received 30 kg N per ha as artificial fertilizer + additional 50, 100 or
150 kg as potato juice.
Fig. 5a. Nitrate concentration in soil water Concentrations of nitrate
nitrogen mg/l 80 cm below surface and calculated drain of water in mm. All
plots with rye grass as catch crop.
Fig. 5b. Concentration of nitrate in soil water. The graph shows the effect
of potato juice given in November.
Fig. 5c. Concentration of nitrogen in soil water. The effect of potato juice
in March before sowing spring barley after rye grass catch crop.
Fig. 5d. Concentration of nitrogen in soil water. The effect of artificial
fertilizer in March. Group A is with spring barley after rye grass catch
crop and group B is spring barley after uncropped fields.
Fig. 5e. Concentration of nitrate in soil water. The effect of potato juice
on uncropped soil during winter. B2 is test of potato juice with
nitrification inhibitor.
Fig. 5f. Concentration of nitrate in soil water. The effect of potato juice
equivalent to 100 kg N/ha on rye grass catch crop at different time.
Fig. 6 Concentration of ammonium in soil water. The concentration of
ammonium nitrogen 80 cm below surface after potato juice with nitrification
inhibitor (100 kg N/ha).
Fig. 7a. Concentration of potassium in soil water. The effects on potassium
concentration mg/l in soil water 80 cm below surface versus time of
application. Graph shows joint results of 50 and 100 kg N/ha.
Fig. 7b. Concentration of potassium in soil water. Potassium concentration
(K mg/l) after different quantities of potato juice in November on rye grass
catch crop. A1 did not receive potato juice.
Fig. 7c. Concentration of potassium in soil water. The effect of artificial
fertilizer in March and potato juice (100 kg N/ha) in November. HG = average
of to levels of artificial fertilizer. Disclaimer. The information contained
in this publication is to the best of our knowledge reliable. Users should,
however, conduct their own tests to determine the suitability of our
products and recommendations for their own specific purposes. Statements
contained herein should not be considered as a warranty of any kind,
expressed or implied, and no liability is accepted for the infringement of
any patent.