Tag Archives: nitrogen

1202-1214 M. Golabadi, P. Golkar and B. Bahari
Remobilization assay of dry matter from different shoot organs under drought stress in wheat (Triticum aestivum L.)
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Remobilization assay of dry matter from different shoot organs under drought stress in wheat (Triticum aestivum L.)

M. Golabadi¹*, P. Golkar² and B. Bahari¹

¹Department of Agronomy and Plant Breeding, Collage of Agriculture, Isfahan (Khorasgan) Branch, Islamic Azad University, P.O. Box: 81595-158 Isfahan, Iran
²Institute of Biotechnology and Bioengineering, Isfahan University of Technology, P.O. Box: 84156-2781 Isfahan, Iran
*Correspondence: m.golabadi@khuisf.ac.ir

Abstract:

Remobilization of dry matter during the grain filling period in wheat is capable of helping the plant recover its grain yield under drought stress. In this study, the genotypic variation of different traits related to dry matter remobilization were measured in seven genotypes of wheat under the three different environment conditions of well-watered, drought stress at heading stage with application of extra nitrogen fertilizer (30%), and drought stress in Isfahan, Iran. Analysis of variance showed that the genotypes were different not only in their dry matter remobilization from the spike, the stem, the peduncle, and the leaf sheath but also in their current photosynthesis. Different environmental conditions were found to affect dry matter remobilization from the leaves and sheath, current photosynthesis, grain yield, and the relative contributions by the stem and the spike to grain yield. The highest values of spike and stem contribution to grain yield were obtained under drought stress while current photosynthesis was found to be the sole supplier for grain filling in normal conditions. Application of extra nitrogen fertilizer under drought stress was found to reduce the loss of grain yield in some genotypes as a result of enhanced vegetative growth, reserve accumulation, and dry matter remobilization to the grain.

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445-452 V. Scholz, J. Kern and P. Kaulfuß
Environmental effects of energy crop cultivation – results of a long-term field trial
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Environmental effects of energy crop cultivation – results of a long-term field trial

V. Scholz¹, J. Kern² and P. Kaulfuß³

¹Leibniz-Institute for Agricultural Engineering Potsdam-Bornim (ATB), Max-Eyth-Allee 100, D-14469 Potsdam, Germany, e-mail: vscholz@atb-potsdam.de
²Postal address above, e-mail: jkern@atb-potsdam.de
³Postal address above, e-mail: pkaulfuss@atb-potsdam.de

Abstract:

In order to identify crop species for sustainable energy farming it is necessary to determine the significance of genetic, environmental and growing-technical factors. Therefore, in 1994 a  long-term practically oriented field experiment on a sandy soil was established to investigate ten annual and perennial plant species and the effects of different N-fertilisation. The measuring programme includes yields, energy gain, N2O emissions as well as ecologically relevant plant and soil constituents. The results of this 15-year trial confirm the possibility of ecological and energy-efficient production of various energy crop species.

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487-492 L. Talgre, E. Lauringson, A, Makke
Amounts of nitrogen and carbon returned to soil depending on green manure and the effect on winter wheat yield
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Amounts of nitrogen and carbon returned to soil depending on green manure and the effect on winter wheat yield

L. Talgre, E. Lauringson, A, Makke

Institute of Agricultural and Environmental Sciences, Estonian University of LifeSciences, Kreutzwaldi St. 1, Tartu, Estonia, e-mail: liina.talgre@emu.ee

Abstract:

The trials were carried out during the 2006–08 growing seasons at the Department of Field Crop Husbandry in the Estonian University of Life Sciences. A field experiment was conducted to investigate the effect of green manure treatments on the yield and yield quality of winter wheat. The total phytomass of leguminous green manures ploughed into soil in 2007 varied from 10.3 Mg ha–1 with the bird’s foot trefoil to 13.9 Mg ha–1 with the white sweet clover. The root mass of legumes comprised 37–54% of the total biomass. The amount of carbon applied into the soil with the green material and roots of legumes varied from 4.43 Mg ha-1 to 5.98 Mg ha–1. The amounts of nitrogen were up to 274 kg of N ha–1. The highest wheat yields were attained in treatments with lucerne and red clover as preceding crops. Compared to the N0 treatment, the extra yield reached 3.26 Mg ha–1 with green manures. Both green manures and mineral fertilizers enhanced the quality of the winter wheat yield, but the results did not vary among different green manures.

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125-132 L. Talgre, E. Lauringson, H. Roostalu and A. Astover
The effects of green manures on yields and yield quality of spring wheat
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The effects of green manures on yields and yield quality of spring wheat

L. Talgre¹, E. Lauringson¹, H. Roostalu² and A. Astover²

¹Department of Field Crops and Grasslands, Institute of Agricultural and Environmental
Sciences, Estonian University of Life Sciences, Tartu, Estonia
²Department of Soil Science and Agrochemistry, Institute of Agricultural and Environmental
Sciences, Estonian University of Life Sciences, Tartu, Estonia
E-mail: liina.talgre@emu.ee

Abstract:

A field experiment was conducted in the period of 2004–2006 to investigate the effect of green manure treatments on the yield and yield quality of spring wheat. In the experiment, different green manure crops were compared for amounts of N, C and organic matter applied into soil and their effect on the yield and yield quality of succeeding cereals. The amount of organic matter applied into soil was dependent on the cultivated crop. The highest amount of organic matter was applied with hybrid lucerne, the lowest, with unfertilised oats. With sowings of red clover, lucerne and hybrid lucerne, 4.91–7.70 Mg C ha-1 and 341.9–379.1 kg N ha-1 were added to soil with green material and roots. The yield of spring wheat on unfertilised soil was 2.12 Mg ha-1, but the treatment with hybrid lucerne as a preceding crop gave an extra yield of 1.45 Mg ha-1. Green manure crops did not have a unilateral effect on the quality of spring wheat. Grain yield grew with the increased norm of mineral nitrogen, but there was no significant improvement in quality indicators.

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5-14 R. Aavola and M. Kärner
Nitrogen uptake at various fertilization levels and cutting frequencies of Lolium species
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Nitrogen uptake at various fertilization levels and cutting frequencies of Lolium species

R. Aavola¹ and M. Kärner²

¹Jõgeva Plant Breeding Institute, Aamisepa 1, 48309 Jõgeva, Estonia;e-mail: rene.aavola@jpbi.ee
²Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences,Kreutzwaldi 5, 51014 Tartu, Estonia; e-mail: malle.karner@emu.ee

Abstract:

A field trial was carried out in 1999–2000 to identify optimal combinations of compound fertilizer rates and defoliation frequencies in perennial ryegrass cv. Raidi (diploid) and Raite (tetraploid) and Italian ryegrass cv. Talvike (tetraploid), to enable the nitrogen (N) requirements of dairy cows to be met. The study aimed at estimating the N utilization in the swards subjected to 6 cycles of simulated grazing or cutting 4 times for silage. N application rates were changed from 0–500 kg ha-1 by 100 kg in the former and from 0–400 by 80 kg ha-1 in the latter harvest regime. Increasing the rate of fertilizer increased the N concentrations and yields. Applying N 300 to ryegrasses defoliated at tillering to stem elongation stage allowed assuring minimum N content in the forage dry matter (2.2%) while at N 500 the upper level (2.7%) was exceeded. The ryegrass plants took up less N than was applied with the compound fertilizer. Increasing the defoliation frequency of grass had a positive effect on N content of the forage, but had inconsistent or no effect on improving N uptake from fertilizer and soil. Perennial ryegrass cultivars were more efficient than Italian ryegrass in taking up N from the soil and fertilizer at simulated grazing. Cutting 4 times a year at moderate to high fertilizer rate applications did not reveal a distinct superiority in N absorption of a particular cultivar, but Italian ryegrass had the best N uptake potential from N deficient soil.

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27-35 L. Buskienė and N. Uselis
The influence of nitrogen and potassium fertilizers on the growth and yield of raspberries cv. ‘Polana’
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The influence of nitrogen and potassium fertilizers on the growth and yield of raspberries cv. ‘Polana’

L. Buskienė¹ and N. Uselis²

¹Lithuanian Institute of Horticulture, LT–-54333 Babtai, Kaunas distr., Lithuania; e-mail:institutas@lsdi.lt
²Lithuanian Institute of Horticulture, LT–-54333 Babtai, Kaunas distr., Lithuania; e-mail:n.uselis@lsdi.lt

Abstract:

The experiment was carried out from 1998–2001 at the Lithuanian Institute of Horticulture, according to the scheme: N60 (control); N60K90; N90; N90K130; N120; N120K180; N150;N150K240. The soil was Epicalcari – Endohypogleic cambisol, clay loam, containing 7.2% oforganic matter, 140 mg kg-1 P2O5, 125 mg kg-1 K2O, 11900 mg kg-1 CaO, 3040 mg kg-1 MgO,pHKCl –7.3.Primocane raspberries cv. ‘Polana’ fertilized with the largest amount of nitrogen fertilizers(N150) produced 20% more primocanes in comparison with the control (N60). Potassiumfertilizers increased the diameter of raspberry stems – fertilizing them with N120K180 stemdiameter resulted in an increase of 5.3%, with N90K130 and by 4.2% with N150K240 incomparison with the control.Primocane raspberries cv. ‘Polana’ fertilized with N120K180 gave the highest yieldincrement – 2.5 t ha-1, and, with N60K90 – 2.4 t ha-1 – in comparison with those fertilized onlywith nitrogen fertilizers (N60).When the rate of nitrogen fertilizers was increased from 60 to 90–150 kg ha-1, the nitrogencontent in the soil increased by approximately 25%. When the rate of potassium fertilizers was increased from 90 to 240 kg ha-1, potassium content in the soil increased to 33%. The content of potassium in raspberry cv. ‘Polana’ leaves significantly increased when fertilizing only with the highest rates of potassium fertilizers (N120K180 – N150K240) – by 12.1–19.7% – in comparisonwith control (N60).

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63–70 E. Lauringson, L. Talgre, H. Roostalu and H. Vipper
The effect of tillage and crop rotation on the content of available nitrogen, phosphorus and potassium
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The effect of tillage and crop rotation on the content of available nitrogen, phosphorus and potassium

E. Lauringson¹, L. Talgre¹, H. Roostalu² and H. Vipper¹

¹Department of Field Crop Husbandry, Estonian Agricultural University, Kreutzwaldi 64, 1008 Tartu, Estonia; e-mail: ennlaur@eau.ee
²Department of Soil Science and Agrochemistry, Estonian Agricultural University, Kreutzwaldi 64, 1008 Tartu, Estonia; e-mail: roostalu@eau.ee

Abstract:

This research (A long-term field experiment from 1982 to 1997) was conducted at the experimental station of the Department of Field Crop Husbandry of the Estonian Agricultural University. The soil of the experimental site is moderately moist slightly podzolised sandy clay.
Insofar as field crop husbandry is concerned the soil should contain optimal amounts of available nutrients. If the level of available nutrients in the soil is low the plants will suffer and the yield will be low. A rise in soil available nutrient content leads to increased yield of crops, but only up to a certain level (optimal content). Thereafter, a further rise in soil nutrient content fails to effect any significant increase in the harvest.
The soils of the Eerika trial plot have optimal nutrient content and little need for fertilisation. After two crop rotations significant changes in nutrient content and location were observed in the ploughed layer. Compared to the nutrient content determined at the start of the trial period (1982), the greatest changes occurred in the soils under a crop rotation involving cereals, potato and a mixture of red clover and timothy, in which the supply of available phosphorus decreased by 19 mg kg-1 and that of potassium by 121 mg kg-1 on average after two rotations. Compared to the cereal rotation and the rotation containing 50% of cereals and 50% of potato the available phosphorus content dropped by 12–33% and the potassium content by 41–46% in the upper 25-cm soil layer.

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229–243 G. Sidlauskas and S. Bernotas
Some factors affecting seed yield of spring oilseed rape (Brassica napus L.)
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Some factors affecting seed yield of spring oilseed rape (Brassica napus L.)

G. Sidlauskas¹ and S. Bernotas²

¹Lithuanian Institute of Agriculture, Akademija 5051, Dotnuva parish, Kedainiai distr., Lithuania, e-mail: gvidas@lzi.lt
²Lithuanian Institute of Agriculture Vezaiciai branch, Vezaiciai, LT-5845 Klaipeda distr., Lithuania, e-mail: filialas@vezaiciai.lzi.lt

Abstract:

The effect of nitrogen rates, time of nitrogen application, concentration of nitrogen, phosphorus and potassium in aboveground plant dry matter, stand population density, mean daily temperature, precipitation rate, growing degree days accumulated by plants at different growing stages and the duration of vegetative growth period on seed yield of Star, a cultivar of Brassica napus L., were studied in the field experiment. The seed yield was significantly affected by nitrogen rates of up to 120  kg ha-1. Further increase in nitrogen fertilisation had only a little effect on the seed yield of spring oilseed rape. There was a possibility to prolong the nitrogen application time until the start of flowering. However, in poorest soils, especially under unfavourable growing and development conditions, late nitrogen application could be much less effective. Nitrogen concentration in plant dry matter at 4–5 leaf stage, at the start and end of flowering and at the seed development stage had a significant effect on seed yield of spring oilseed rape. Phosphorus concentration was not important in the second part of vegetative growth. Potassium concentration, on the contrary, in the first part. With an increase of stand population density to up to 170 plant m-2 seed yield of spring oilseed rape was increasing. The increase in the duration of vegetative growth period and precipitation rate resulted in a higher seed yield. Meanwhile, the increase of mean daily temperatures and growing degree days had a negative effect on seed yield of spring oilseed rape. Presented regression equations could be used for a model for prognosis of seed yield of spring oilseed rape, based on agronomic and climatic factors.

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3–10 M. Alaru, Ü. Laur and E. Jaama
Influence of nitrogen and weather conditions on the grain quality of winter triticale
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Influence of nitrogen and weather conditions on the grain quality of winter triticale

M. Alaru, Ü. Laur and E. Jaama

Department of Field Crop Husbandry, Estonian Agricultural University, Kreutzwaldi 64, 51008 Tartu, Estonia; e-mail: malaru@hot.ee

Abstract:

The protein content and  falling numbers of five winter triticale cultivars were tested in very different weather conditions (1998/1999–2000/2001) on Stagnic Luvisol soils (WRB classification) in the experimental fields of the Department of Field Crop Husbandry of the Estonian Agricultural University near Tartu (58°23´N, 26°44´E). All cultivars were fertilised with nitrogen fertiliser (NH4NO3) in early spring, using a norm of 0–200 kg N ha-1 (increasing the amonts of fertiliser by 20 kg ha-1). Fertilising with nitrogen after hibernation at the tillering stage in early spring increased the protein content of  seeds averaged over years and cultivars by up to 1.57% in dry matter. Protein levels depended most on the cultivar, less on the weather conditions of the growth year and least  on the nitrogen fertiliser (the determination indices of a dispersion analysis were 0.35, 0.32 and 0.14, respectively). The yield and protein content were in negative correlation (r = 0,92*). Due to very different weather conditions during the growth period, the figures of the falling number were very different in different years.

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