Search

Published After
Published Before

Search Results

  • The effect of fertilization on the feeding value and nutrient yield of artificial grasslands 2.
    46-56
    Views:
    62

    The 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. Quality and nutrient yields 8.
    119-128
    Views:
    45

    The 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.