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.

Key words:

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.

Key words:

biomass, crude protein, gluten index, grain yield, green manure crops, nitrogen, spring wheat