Tag Archives: grain yield

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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517-529 I. Małecka and A. Blecharczyk
Effect of tillage systems, mulches and nitrogen fertilization on spring barley (Hordeum vulgare)
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Effect of tillage systems, mulches and nitrogen fertilization on spring barley (Hordeum vulgare)

I. Małecka¹ and A. Blecharczyk²

¹ Poznan University of Life Sciences, Plant and Soil Cultivation Department, Mazowiecka45/46, 60-623 Poznan, Poland; e-mail: malecka@up.poznan.pl
² Poznan University of Life Sciences, Plant and Soil Cultivation Department, Mazowiecka45/46, 60-623 Poznan, Poland; e-mail: blechar@up.poznan.pl

Abstract:

Yield, N uptake, weeds and diseases of spring barley were examined under five mulching practices (white mustard, phacelia, oat-pea mixture, straw mulch, and no mulch), three tillage systems (conventional, reduced and no-tillage) and three doses of nitrogen fertilization (0, 50 and 100 kg N ha-1). In general the grain yield of spring barley for cover crops was 10-31% higher compared with the no-mulch treatment. A mulch of straw provided a smaller barley grain yield than the no-mulch treatment. Compared to conventional tillage, grain yield under reduced tillage and no-tillage were 7 and 12% less, respectively. Spring barley sowing after a mixture of oat-pea led to decreased a negative response of reduced and no-tillage. Grain yield after treatment with legume cover crops and without N fertilization was similar compared as the rates 50 kg N ha-1 after white mustard or phacelia and as the rate 100 kg N ha-1 without mulches. There was no evidence of tillage x N fertilization interaction on grain yield, dry matter production and plant-N uptake. Cover crops and straw mulch significantly decreased total weed populations compared with the treatment without mulch. Total weed density increased from 108 plants per m2 in the no-tillage to 322 plants per m2 for reduced tillage, and to 416 plants per m2 for the conventional tillage over mulch. Higher infestation of spring barley with stem base and root diseases was observed in reduced and no-tillage in comparison with the conventional soil tillage and after straw mulch and no-mulch than after cover crops.

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379-383 R. Smatas
The occurrence and control of aphids and thrips in winter triticale
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The occurrence and control of aphids and thrips in winter triticale

R. Smatas

Lithuanian Institute of Agriculture, Instituto aleja 1, Akademija, Kedainiai dist., LT58344,Lithuania; remigijus@lzi.lt

Abstract:

Studies were carried out at the Lithuanian Institute of Agriculture during the period 2002–2004. Contact and systemic insecticides were used for pest control in winter triticale. Pesticide application timing was determined according to the threshold of harmfulness of thrips and aphids. In our investigation we used as the threshold of thrips’ harmfulness, 1–2 pests per stem, and for aphids, 5–10 pests per stem. Our results suggest that thrips and aphids were the main pests occurring in winter triticale crops during the experimental years. The occurrence of thrips was more intensive in 2002 and 2003 than in 2004. The occurrence of aphids was the most intensive in 2002, less intensive in 2004. Almost no aphids were found in 2003. The appearance of aphids in 2004 was later compared with that in 2002. Both insecticides reduced the occurrence of thrips and aphids. The winter triticale grain yield was higher in the plots applied with insecticides.

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177–187 R. Põldaru, J. Roots and A.-H. Viira
Artificial neural network as an alternative to multiple regression analysis for estimating the parameters of econometric models
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Artificial neural network as an alternative to multiple regression analysis for estimating the parameters of econometric models

R. Põldaru¹, J. Roots¹ and A.-H. Viira²

¹Institute of Economics and Social Sciences, Estonian University of Life Sciences, Kreutzwaldi 64, 51014 Tartu, Estonia; e-mail: Reet.Poldaru@emu.ee, Jyri.Roots@emu.ee
²ARIB, Narva 3, 51009, Tartu, Estonia; e-mail: Ants.Viira@pria.ee

Abstract:

In recent years, neural networks have been used for a wide variety of applications where statistical methods are traditionally employed. Neural nets offer the opportunity to create a model by using technology similar to the learning patterns of the human brain. The structure of artificial neural networks (ANN) is based on the human brain’s biological neural processes. Artificial neural networks provide a new approach to the problem of parameter estimation of nonlinear econometric models. This paper presents a comparison between neural networks and econometric approaches for estimation of parameters of an econometric model of grain yield. The aim of this study is to show that neural nets are a convenient econometric tool. The parameters were estimated on the basis of alternative variants of models. The analysis shows that artificial neural network models may be used for parameter estimation of the econometric models.

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99–103 Ü. Tamm
The variation of agronomic characteristics of European malting barley varieties
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The variation of agronomic characteristics of European malting barley varieties

Ü. Tamm

Jõgeva Plant Breeding Institute, 48309 Jõgeva, Estonia; e-mail: Ylle.Tamm@jpbi.ee

Abstract:

The field experiments were carried out in 1999_2002 at the Jõgeva Plant Breeding Institute (PBI) in Estonia to investigate the genetic and environmental variation of agronomic characteristics of malting barley. 57 malting barley varieties were included in the trials. Grain yield, number of tillers per 1m², plant height, lodging resistance and growing time were measured in the trial with malting barley.
 Despite very different weather conditions, the grain yield stability of malting barley varieties was very high. Tillering  showed somewhat lower genetic variability compared to the variation of grain yield. The plant height indicates moderate genetic variability. Lodging resistance and growing time showed  low genetic variability.

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93–97 I. Tamm
Genetic and environmental variation of grain yield of oat varieties
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Genetic and environmental variation of grain yield of oat varieties

I. Tamm

Jõgeva Plant Breeding Institute, 48309 Jõgeva, Estonia; e-mail: Ilmar.Tamm @jpbi.ee

Abstract:

Both variety genotype and climatic conditions influence the grain yield of oat. The field experiments were carried out in 1998_2002 at the Jõgeva Plant Breeding Institute (PBI) in Estonia to investigate the genetic and environmental variation of oat grain yield. 101 oat varieties from Germany, Sweden, Russia, Canada, USA, and other countries were included in the trial.
    As a result of the trial, the climatic conditions proved to have considerable influence on the grain yield of oat. Oat grain yield was decreased by drought and high temperatures in 1999 and 2002. Heavy winds and rains caused  lodging of oat crop and lowered the grain yield in 1998 and 2001. The oat grain yield was highest in 2000, in rainy vegetaton period with moderate temperature. The coefficients of variation and differences between minimum and maximum values indicate the wide range of genetic variability of grain yield.

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