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First results of the cultivation of prairie grass (Bromus catharticus Vahl) in Hungary
9-18Views:128Yield elements (plant height, grass yield) of prairie grass, the little known grass species in Hungary, was investigated in a three-factor field experiment set up on the Mohács-island. One-grass and grass/legume mixture were established under irrigated and non-irrigated conditions at different nitrogen levels (0-67-133 kg N/ha/year). The effects of these factors on the grass productivity were analysed by a three-factor analysis of variance at 5% significance level in the first year of the experiment. Nitrogen supplementation and the interaction of legumeXirrigation had a significant positive effect on the annual hay yield. The yield of the first two cuts, which accounted for 61% of the annual yield, was not significantly affected by any of the examined factors, while their effect was already clearly visible in the yield of the 3rd and 4th cuts. A similar result was obtained with the model fitted to the average height of the four cuts, but the legumeXirrigation and legumeXnitrogen interactions were already significant in the 2nd cut. Nitrogen had a positive effect on grass height from the 3rd cut. Without irrigation, the 1st cut showed a significantly lower grass height with legume addition. In our experiment, we estimated 65 t/ha annual fresh grass yield on average of the treatments, and 18 t/ha of hay was actually harvested. In the treatment of irrigation with legume addition, 1 kg/ha of excess nitrogen resulted in an excess of 150 kg/ha of fresh grass yield in the case of the higher dose nitrogen treatment, compared to the nitrogen control. The laboratory analysis of the 1st cut-hay samples from selected treatments confirmed favorable protein (16.7-18.2%) and crude fat content, its lower crude fiber content and higher calcium and phosphorus content compared to cocksfoot and smooth brome.
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Comparison of the production of fenugreek (Trichonella foenum-graecum) experiments in 2018-2020
11-14Views:135The aim of our study is to compare the results (content values, yield) of fenugreek (Trigonella foenum-graecum L.) experiments in 2018-2020. Fenugreek is an annual herbaceous plant belonging to the legumes (Fabaceae) family. It is a multifunctional crop for use in domestic and farm animal feeds, wild fodder, herbs and spices. During the study period, nutrient supply treatments were applied to increase the production values of the plant. The weed suppressing ability of fenugreek in the post-emergence period (1-3 weeks) is very poor, so we had to use chemical weed control. During the experiment, the T. foenum-graecum stock was irrigated. The plant was harvested 80-90 days after sowing. The study was carried out in Kecskemét in 2018-2019, at the Demonstration Garden of John von Neumann University, Faculty of Horticulture and Rural Development. The 2020 experiment was set up at the University of Szeged, Faculty of Agriculture.
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The effect of sheep manure the yield of primary growth o fan extensive natural grassland
27-30Views:70An experiment with overriped sheep-manure was carried out to make the environmental protective technology of nutrition on a cut grassland in the Karcag Research Institute of University of Debrecen, CAS. Based on our research results gained from a 4 year field experiment of Alopecuretum pratensis grassland association we have concluded that the 20 t/ha overriped sheep-manure the was optimum rate most favourable from economical point of niev and for increasing the rate of clovers in the sward.
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Effect of fertilization on the mineral element uptake of an established all-grass sward 4.
3-10Views:57The effects of different N, P and K supply levels and their combinations were examined on the mineral element uptake of an established all-grass sward with seed mixture of eight grass species in the 28th year of a long term fertilization field experiment set up on a calcareous chernozem loamy soil. The lay-out and method of the trial as well as the fertilizer responses on the hay yield, nutritional values and element content were published elsewhere (Kádár, 2005, 2005a; Kádár és Győri, 2005). The soil of the growing site contained around 3% humus, 5% CaCO3, 20-22% clay in the ploughed layer and was originally, moderately well supplied with available K, Mg, Mn and Cu and poorly supplied with P and Zn. The trial included 4Nx4Px4K=64 treatments in 2 replications, giving a total of 128 plots. The fertilizers applied were Ca-ammonium nitrate, superphosphate and potassium chloride. The groundwater table was at a depth of 13-15 m, the area was prone to drought. In 2001, however, the area had satisfactory amount of 621 mm precipitation with a fairly good distribution. The grass was established on 21. September 2000. The main results and conclusions can be summarised as follows:
1. As a function of NxP positive interactions the element uptake of the 1st cut hay expressed as mean of K treatments increased between the N0P0 control and the maximum N3P3 levels as follows: K 62-190, N 45-218, Ca 16-51, S 5-24, P 4-24, Mg 4-16, Na 0.5-5.0 kg/ha; Mn 282-968, Sr 35-170, Zn 32-73, Ba 29-55, B 18-44, Cu 8-40 g/ha. The uptake of Ba increased from 23 to 62 g/ha, that of Ni from 1.5 to 8.9 g/ha as a result of KxP positive interactions. Uptake of Mo measure on K0P0 soil, however, dropped from 1.6 g/ha to 0.4 g/ha on the K3P3 soil as a function of negative KxP interactions.
2. The 2nd cut hay harvested on 9th October 2001 showed only N-effects. The hay yield measured on N-control soil was 1.0 t/ha while on 300 kg/ha/yr N-treatment 3.9 t/ha. The uptake of Fe, Ba and Mo increased 2-fold; uptake of Ca, S, P, Sr, Zn and Co 3-4-fold, uptake of K, N, Mg, Mn, Ba and Cu 5-6-fold, while uptake of Na 33-fold with the maximum N-rate, compared to the N-control and as means of PK treatments.
3. The 2 cuts together gave on the unfertilised control 3 t/ha, while on the N3P3K3 maximum supply level 13 t/ha hay yield. The uptake of Fe, Cr, B, Ni, Mo and Co increased 2-3 times, uptake of Ca, Mg, Mn, K, Zn, Ba and Cu 5-6 times, uptake of S, Sr and P 7-8 times, uptake of N 10 times, while uptake of Na 16 times on the maximum N3P3K3 supply levels, compared to the unfertilised control. The maximal mass of uptaken K and N made up 388 kg/ha, Ca 80 kg/ha, S 49 kg/ha, P 42 kg/ha (96 kg/ha P2O5), Mg 24 kg/ha in 2001.
4. To have 1 t of air-dry hay it was used by grasses as a mean of 25 kg K (30 kg K2O), 20 kg N, 6 kg Ca (8-9 kg CaO), 2-3 kg S, 2 kg P (5 kg P2O5) and 2 kg Mg (3-4 kg MgO). For microelements: 300 g Na, 200 g Fe, 120 g Mn, 100 g Al, 16 g Sr, 13 g Zn, 8 g Ba, 5 g B, 5 g Cu, 1-2 g Ni, 1 g Mo, 0.2 g Cr and 0.1 g Co. The As, Hg Cd, Pb and Se were under detection limit of 1 g. Data may serve for assessing the nutrient demand of all-grass sward. -
The effects of fertilization on 2 year old established swards. Quality and nutrient yields 8.
119-128Views:61The effects of different N, P and K supply levels and their combinations were examined on the quality nutritional values and nutrient yield of an established 2 year old all-grass sward in the 29th year of a long-term fertilization field experiment set up on a calcareous chernozem soil. The soil of the growing site contained around 3% humus, 3-5% CaCO3, 20-22% clay in the ploughed layer and was originally moderately well supplied with available N, K, Mg, Mn and Cu and poorly supplied with P and Zn. The trial included 4Nx4Px4K=64 treatments in 2 replications, giving a total of 128 plots. The fertilizers applied were Ca-ammonium nitrate, superphosphate and potassium chloride. The groundwater table was at a depth of 13-15 m and the area was prone to drought. In 2002, the area had 401 mm precipitation and gave 2 cuts of grass. The 1st year results of the trial were published earlier (Kádár, 2005a, b). The main conclusions can be summarised as follows:
1. The N-responses were decisive for both the hay quality and the hay and nutrient yields. The N-fertilizer increased the crude protein content and diminished the same time the crude fibre, crude ash and total sugar contents in the hay. The P-responses were not significant while the K-fertilization stimulated the crude ash accumulation in both cuts.
2. The hay yield of 2 cuts in 2002 amounted to 1,7 t/ha on the N0P0K0 plots not receiving any fertilizer during the 29 experimental years, while on the maximum N3P3K3 supply levels figured out 8.7 t/ha. The same time here the crude fibre increased from 532 kg/ha to 2876 kg/ha, crude protein from 113 kg/ha to 1100 kg/ha, crude ash from 132 kg/ha to 672 kg/ha, crude fat from 39 kg/ha to 173 kg/ha, while the crude fibre/crude protein ratio dropped from 4.7 to 2.6.
3. After 3 years storing the decisive part of carotine decomposed in the hay and gave as little as 0.9 mg/kg average value. The N-control gave 0.6 mg/kg, the 200 kg/ha/yr N-treatment resulted in 1.3 mg/kg, than the N-excess 300 kg/ha/yr plots showed again significantly less 0.9 mg/kg.
4. The 2nd cut hay had a little yield however, was rich in crude protein and crude ash having 50-70% higher average content compared with the primary hay. The crude fat content was 3-times higher in the 2nd cut hay, while the crude fibre about 20% less. The ratio of crude fibre/crude protein figured as an average 1.9, while in the low-quality primary hay amounted 4.2.
5. The N-fertilization depressed the content of N-free extract and acid detergent fibre (ADF) and enhanced the content of energy dependent protein (MFE), N-dependent metabolic protein (MFN) and nettoenergy (NE) parameters. The P fertilization did not cause any changes, while the K-fertilization decreased the N-free extract and the nettoenergy parameters (NE) and slightly stimulated the neutral detergent fibre (NDF) synthesis in the 2nd cut hay. -
The effect of fertilization on the mineral contant of artificial grasslands 3.
57-66Views:83The effects of different N, P and K supply levels and their combinations were examined on the mineral element content of an established all-grass sward with seed mixture of eight grass species in the 28th year of a long term fertilization field experiment set up on a calcareous chernozem loamy soil. The lay-out and method of the trial as well as the fertilizer responses on the hay yield were published elsewhere (Kádár 2004). The effect of fertilization on the nutritional values and nutrient yield also described earlier (Kádár and Győri, 2005). The soil of the growing site contained around 3% humus, 5% CaCO3, 20-22% clay in the ploughed layer and was originally, moderately well supplied with available K, Mg, Mn and Cu and poorly supplied with P and Zn. The trial included 4Nx4Px4K=64 treatments in 2 replications, giving a total of 128 plots. The fertilizers applied were Ca-ammonium nitrate, superphosphate and potassium chloride. The groundwater table was at a depth of 13-15 m, the area was prone to drought. In 2001, however the area had a satisfactory amount of 621mm precipitation with a fairly good distribution. The grass was established on 21. September 2000. The main results and conclusions can be summarised as follows:
1. As a function of N-fertilization the element content of the 1st cut hay usually increased, except for Al and Mo, which showed dilution effects. The concentration of K, Ca, Mg, Mn, P, Sr, B, Ni enhanced with 25-50%, S and Co with 60-70%, N and Cu 2-times, NO3-N and Na about 5-times compared to the N-control. The P-fertilization stimulated uptake of Mn and Mg for 10-20%; S, NO3-N and Co for 40-50%, Na and for Sr 60-70%, P for 90%, however, inhibited the uptake of Zn and Co for 20-40%, Al and Fe for 50-60%, Mo for 70% compared to the P-control.
2. The P/Zn ratio showed on P-control soil optimal values of 118, while on highly P-supplied soil 278 P/Zn ratio, so indicating Zn-deficiency. As a function of PxK negative interactions, concentration of Fe dropped from 307 to 105 Al from 206 to 60, Mo from 0.44 to 0.05, Cr from 0.33 to 0.12 mg/kg in air-dry hay. The Cu/Mo ration on N-control soil showed the optimal value of approx. 10, while on heavily fertilized with N soil that of 40-80, indicating extreme Mo-deficiency.
3. The 2nd cut hay contained about 20% more N, K, Ca, Mg, Na, 40% more Cu, 70-80% more S and Mn, 90% more Fe and P, 140% more Al and nearly 5-times more Mo. The content of B did not changed, while NO3-N dropped about 40% . The Cu/Mo ratio showed value of 2.6 on N-control soil, while on heavily fertilized with N soil ratio of 7.8. The P/Zn ratio indicated on P-control soil optimal value of 150, while on overfertilized with P soil value of 269. So, the P-induced Zn-deficiency could also be proven in the 2nd cut hay, while the Cu-induced Mo-deficiency disappered.
4. The N-fertilization stimulated in the 2nd cut hay also the accumulation of elements N, K, Mg, P, Mn, Cu and Ni with 20-50% compared to the N-control. The NO3-N increased 4-times, while Na content 10-times. However the elements Fe, Al, B, Mo and Cr showed a dilution effect with 20-60%. The P-fertilization increased the concentration of Mn, Sr, Cd, Co, S and P, while decreased the content of Na, NO3-N, Cu and Zn. As a general rule, the K-fertilization hindered the accumulation of metal cations. The P-induced Cd accumulation was fully counterbalanced by increasing K-supply of soil.
5. Summarizing above we can state that the long-term fertilization can drastically (in some cases with an order of magnitude) change the concentrations and ratios of elements built in hay through synergetic or antagonistic effects. In the 1st cut hay, for example, the minima-maxima contents of measured elements varied in air-dry hay as follows: N 0.90-3.02, Ca 0.4-0.7, S 0.14-0.32, P 0.12-0.30, Mg 0.10-0.24%; Na 70-700, Fe 100-288, Al 45-250, Mn 71-130, Sr 10-22, Zn 7-14, Ba 6-11, B 3.6-8.1, Ni 0.3-1.6, Cr 0.1-0.4, Mo 0.04-0.44, Co 0.04-0.12 mg/kg. -
The effects of fertilization on 2 year old established swards. Mineral uptake 7.
107-118Views:52The effects of different N, P and K supply levels and their combinations were examined on the mineral element uptake of an established 2 year old all-grass sward in the 29th year of a long-term fertilization field experiment set up on a calcareous chernozem soil. The soil of the growing site contained around 3% humus, 3-5% CaCO3, 20-22% clay in the ploughed layer and was originally moderately well supplied with available N, K, Mg, Mn and Cu and poorly supplied with P and Zn. The trial included 4N×4P×4K=64 treatments in 2 replications, giving a total of 128 plots. The fertilizers applied were Ca-ammonium nitrate, superphosphate and potassium chloride. The groundwater table was at a depth of 13-15 m and the area was prone to drought. In 2002 the area had 401 mm precipitation and gave 2 cuts of grass. The lay-out and method of the trial as well as the fertilizer responses on the hay yield and element content were published earlier (Kádár 2006). The main conclusions drawn as follows:
1. While the hay yield was basically determined by N-fertilization which lifted the hay mass 5 times compared to the N-control, the uptake of elements was drastically modified through the N×K and N×P synergistic and antagonistic interactions.
2. As a function of N×K treatments the uptake K changed for example at the 1st cut between 23-198 kg/ha, at the 2nd cut between 9-80 kg/ha. At the same time the uptake of Na fluctuated between 0.05-7.15 kg and 0.4-4.4 kg/ha, that of Mo 0.4-3.2 g/ha and 0.2-2.3 g/ha resp. As a function of N×P treatments the uptake of P changed at the 1st cut between 3-14 kg/ha, Sr between 12-388 g/ha, Mo between 0.5-4.5 g/ha. The nutrient accumulation at the 2nd cut showed an analogical picture.
3. The K-fertilization stimulated accumulation of K and Ba, while inhibited the antagonistic metal cations’ uptake of Ca, Mg and Na. The increased P-supply rose the absorption of P, S, Sr and Ba while diminished the extracted amount of Mo, which dropped down by 1/3rd compared with the control. The liberal N-supply stimulated the incorporation of N, K, Mn, Sr and Cu resulting an increase of an order of magnitude.
4. Between the two extreme supply levels (N0P0K0 and N3P3K3) there were found extreme differences in element uptake in 2002 as follows: 34-302 kg/ha K, 15-168 kg/ha N, 8-35 kg/ha Ca, 5-22 kg/ha S, 4-22 kg/ha P (9-51 kg/ha P2O5) and 3-14 kg/ha Mg. The incorporated Mn, Sr, Zn and Cu enhanced an order of magnitude on N3P3K3 plots compared to the N0P0K0 absolute control. Uptake of As, Cd, Co, Cr, Hg, Pb and Se left behind the detection limit of 1 g/ha.
5. To have 1 t air-dry hay it was used by grasses 17-35 kg K, 9-19 kg N, 3-5 kg Ca, 2.0-2.5 kg S, 1.3-2.5 kg P (3.0-5.7 kg P2O5), 1.4-1.9 kg Mg, 170-980 g Na, 90-170 g Fe, 60-120 g Mn and Al, 10-50 g Sr, 7-25 g Zn, 3-6 g Ba, B and Cu, 0.3-1.3 g Mo and 0.4-0.9 g Ni. Data illustrate the nutrient turnover of a grassland and may be used for assessing the nutrient demand of all-grass sward. -
The effect of fertilization on the feeding value and nutrient yield of artificial grasslands 2.
46-56Views:76The effect of different N, P and K supply levels and their combinations on the nutritional values and nutrient yield of an established all-grass sward were examined in 28th year of a long-term fertilization field experiment set up on a calcareous chernozem loamy soil. The fertilizer responses on the development, hay yield and N-uptake were published elsewhere (Kádár, 1994). The soil of the growing site contained around 3% humus, 5% CaCO3, 20-22% clay in the ploughed layer and was originally moderately well supplied with available K, Mg, Mn and Cu and poorly supplied with P and Zn. The trial included 4Nx4Px4K=64 treatments in 2 replications, giving a total of 128 plots. The fertilizers applied were Ca-ammonium nitrate, superphosphate and potassium chloride. The groundwater table was at a depth of 13-15 m and the area was prone to drought. In 2001, however, the area had a satisfactory amount of 621 mm precipitation with fairly good distribution. The grass was established on 21. September 2000. The main results and conclusions can be summarised as follows:
1. While the grass herbage yield was determined by the NxP supply levels, the nutritional values were influenced by the NxK interactions. As a function of NxK treatments, the N-free extract decreased from 532 g/kg (control) to 390 g/kg (N3K3), Crude-protein increased on the same plots from 64 g/kg to 183 g/kg, so the ratio of N-free extract/Crude-protein tightened from 8.3 to 2.1. Compared to the unfertilized control, the Crude-ash enhanced with 26%, while the N-dependent Metabolic Protein (MFN) with 286% on the N3K3 levels.
2. The maximum nutrient yields were measured at the first cut on the 100 kg/ha/yr N-treatment with 150 mg/kg ammoniumlactate soluble P-supply soils for Crude-fibre, Neutral and Acid Detergent Fibres (NDF, ADF) N-free extract, Crude-ash and Nettoenergy (NE) parameters. The Crude-fat and the Energy Dependent Protein (MFE) yields gave maximum surpluses using 200 kg/ha/yr N-rate with high level of 333 mg/kg AL-P2O5 supply in plow-layer. Highest crude-protein and the N-dependent Metabolic Protein (MFN) yields were connected, however, to the highest N3P3 levels, where the yield increased 5-times compared to the control.
3. At the 2nd cut, both the nutritional values and the nutrient yields changed only as a function of N-supply. Maximum nutrient yields were obtain generally at the 300 kg/ha/yr treatment. Assessing the 1st and 2nd cuts together, the 200 kg/ha/yr treatment seemed to be the best fertilization practice. Among the different NPK treatments developed extreme differences. The unfertilized for 28 years plots (N0P0K0 ) gave small nutrient yields. The moderate N-fertilization alone (N1P0K0) enhanced the yields 2-3 times. The moderate balanced fertilization (N1P1K1) gave further dramatic surpluses. The N-dependent Crude-protein and the protein fractions (MFE, MFN) as well as the Crude-fat yielded maxima values at the highest (N3P3K3) treatment.
4. Summarizing above, we can state that the satisfactory or abundant fertilization on such soil poor in NPK and in a favourable year can increase the Crude-fibre, the fiber fractions (NDF, ADF), N-free extract, Crude-ash, Crude-fat and Nettoenergy (NE) yields 3-5 times, while the N-dependent Crude-protein and protein-fractions (MFE, MFN) even 7-8-times. -
The effects of fertilization on 2 year old established swards. Yield and mineral content 6.
94-106Views:58The effects of different N, P and K supply levels and their combinations were examined on the hay yield and mineral element content of an established 2 year old all-grass sward in the 29th year of a long-term fertilization field experiment set up on a calcareous chernozem soil. The soil of the growing site contained around 3% humus, 3-5% CaCO3, 20-22% clay in the ploughed layer and was originally moderately well supplied with available N, K, Mg, Mn and Cu and poorly supplied with P and Zn. The trial included 4N×4P×4K=64 treatments in 2 replications, giving a total of 128 plots. The fertilizers applied were Ca-ammonium nitrate, superphosphate and potassium chloride. The groundwater table was at a depth of 13-15 m and the area was prone to drought. In 2002, the area had 401 mm precipitation and gave 2 cuts of grass. The 1st year results of the trial were published earlier (Kádár, 2005a, b). The main conclusions can be summarised as follows:
1. As a function of N×P fertilization the two cuts of the hay yield made up 1.4-8.0 t/ha while the green herbage 5.0-24.0 t/ha. The N-fertilization was of vital importance, which increased the hay mass 5 times. The P-response was moderate in the 1st, cut while there were no K-responses at all on this soil with 135 mg/kg ammoniumlactate (AL) soluble K2O values in plough layer.
2. On those plots well supplied with PK the 100 kg/ha/yr N-treatment gave a total of 48 kg surplus hay/kg N applied. The 200 kg/ha/yr N-treatment yielded 11 kg, while the 300 kg/ha/yr N-treatment yielded 4 kg surplus hay/kg N applied. The NO3-N content of the 1st cut hay increased over permitted 0.25% level when using the maximum N-rate and made up this NO3-N form 26% of the total-N pool. The optimum PK-supplies in this site seems to be about 130-150 mg/kg AL-P2O5 and AL-K2O in plow layer with 200 kg/ha/yr N applied.
3. N-fertilization enhanced the content of N, K, Mg, Na, Mn, Cu and NO3-N, while the concentration of S, P, Al, Fe, B and Mo dropped in the primary hay. The increasing P-supply stimulated the uptake of P, Ca, Mn, Sr and Ba, while hinderned the uptake of S and Mo. The K-fertilization rose the content of K and Ba and diminished the concentration of Mo and the antagonistic metal cations like Ca, Mg and Na.
4. The NPK fertilization-induced Mo-deficiency can first of all jeopardized the fodder quality in this site. On the unfertilized plots the hay showed around 1.0 mg Mo /kg D.M., while on the N3P3K3 plots 0.1-0.2 mg/kg D.M. The P/Mo ratio lifted from 2-4 thousand up to 20 thousand. In the 2nd cut this phenomena partly disappeared, while developed the P-Zn antagonism. On P-control plots measured 15 mg/kg Zn
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GYEPGAZDÁLKODÁSI KÖZLEMÉNYEK, 2006/4.
dropped to 10 mg/kg while the P/Zn ratio rose from 167 up to 364.
5. The 2nd cut hay had a little yield, yet was rich in minerals having 30-50% higher average element content compared with the primary hay. However the N, Al, Fe and Mo showed 2-times higher concentrations in the 2nd cut hay. There were found extra large, 25-fold differences in hay Na content as a function of N×K supply levels under synergetic effect of N and antagonistic effect of K treatment.
6. Summarizing the above we can state that the long-term fertilization may drastically change the content and ratios of elements built in hay through synergetic or antagonistic effects. In the air-dried 1st cut hay for example, the minima-maxima concentrations of measured elements varied as follows: N 0.7-3.0%, K 1.3-3.0%, Ca 0.3-0.5%, Mg 0.13-0.21%, S 0.15-0.32%, P 0.10-0.32%; Na 50-1400, Mn 60-120, Al 50-120, Fe 70-140, Sr 8-170, Zn 6-40, Ba and B 3-6, Cu 2.5-5.5, Ni 0.4-1.4, Mo 0.1-1.0 mg/kg. -
Effect of fertilization on the aminoacid content and aminoacid yield an established all-grass swarde 5.
11-20Views:79The effects of different N, P and K supply levels and their combinations were examined on the amino acid content and yield of an established all-grass sward with seed mixture of eight grass species in the 28th year of a long term fertilization field experiment set up on a calcareous chernozem loamy soil. The lay-out and method of the trial, as well as the fertilizer responses on the hay yield and quality parameters, were published elsewhere (Kádár, 2005; Kádár and Győri, 2005). The soil of the growing site contained around 3% humus, 5% CaCO3, 20-22% clay in the ploughed layer and was originally moderately well supplied with available K, Mg, Mn and Cu and poorly supplied with P and Zn. The trial included 4Nx4Px4K=64 treatments in 2 replications, giving a total of 128 plots. The fertilizers applied were Ca-ammonium nitrate, superphosphate and potassium chloride. The groundwater table was at a depth of 13-15 m and the area was prone to drought. In 2001, however, the area had a satisfactory amount of 621mm precipitation with a fairly good distribution. The grass was established on 21. September 2000. The main results and conclusions can be summarised as follows:
1. The content of GLU, ASP, HIS and ARG increased in the crude protein of the 1st cut hay as a function of N-fertilization up to 12-19%. The same time the content of PRO decreased up to 23%, CYS up to 25%, TRY up to 42% and ALA up to 48% compared to the N-control. The P fertilization raised the concentration of ASP, LEU, GLY, HIS, PHE and CYS, while the content of ALA dropped down to 41% that of P-contol.
2. As a function of NxP positive interactions the content of ASP rose from 7.2 to 10.3%, HIS from 3.8 to 5.8%, ARG from 3.2 to 4.2% compared to the NP control, while the content of ALA diminished from 5.8 to 2.2%, TRY from 1.3 to 0.6%. The K fertilization also depressed the TRY synthesis. The N0P0K0 plots showed 1.59% TRY in protein, while the N3P3K3 maximum supply plots only 0.35%.
3. The yield of amino acids was enhanced 3-4 times by N fertilization, 2.0-2.5 times by P fertilization and 20-30% by K fertilization. The amino acid yield increased on the N3P3K3 plots, compared to the N0P0K0 plots, in the case of ALA and TRY 3-4 times. Most of the other amino acids yielded 8-12 times more, HIS 14 times, PRO 16 times, GLY 18 times and CYS 20 times more. The maximum yield of essential amino acids made up 774 kg/ha, the total amino acid yield 1552 kg/ha and crude-protein 1779 kg/ha in the 1st cut hay.
4. As a result of NxP interactions the ratio of ASP/ALA changed from 1.2 to 4.7, that of ARG/TRY from 2.5 to 6.3, that of HIS/TRY from 2.9 to 9.7 with the increased NP supply. Thus, fertilization can induce an imbalance of amino acids and so change or deteriorate the biological quality of protein. In similar circumstances the forage may require a TRY supplement to restore the imbalance of amino acids.