ISSN 1392-3196 / e-ISSN 2335-8947
Zemdirbyste-Agriculture, vol. 105, No. 3 (2018), p. 221–226
DOI  10.13080/z-a.2018.105.028

Changes in weed seed bank and flora as affected by soil tillage systems



Tillage not only changes soil properties but also serves as a weed control means. Different soil tillage systems were investigated in a long-term field experiment conducted during 2003–2012 at Institute of Agriculture, Lithuanian Research Centre for Agriculture and Forestry. The experiment was carried out in a cereal-based crop rotation. The experimental design included the following tillage treatments: 1) conventional tillage (CT): mouldboard ploughing at 22–24 cm depth; 2) minimum tillage (MT): stubble cultivation at 10–12 cm depth, non-selective herbicide (glyphosate) spray applied after harvesting; 3) no tillage (NT): direct drilling, non-selective herbicide spray applied after harvesting. This paper presents the data from the 2007–2012 experimental period. To determine weed seed bank, soil samples were taken in 2007 after spring barley harvesting and in 2012 after winter oilseed rape harvesting. Samples of weeds for the determination of fresh and dry mass were collected in 2011 and 2012 in winter wheat and winter oilseed rape crops during the growing period.

The weed seed bank in the soil significantly decreased over the five-year period. However, significantly the highest number of seeds in the soil was found in the no tillage plots. Significant differences in the weed species composition between the different tillage systems were recorded: no tillage system promoted infestation of some broadleaf weeds, particularly Capsella bursa-pastoris. The lowest weed mass was determined for the conventional tillage plots, compared to minimum tillage, and especially no tillage plots.

Key words: soil, species composition, tillage, weeds, weed mass, weed seed bank.

Full text: 105_3_str28.pdf