ISSN 1392-3196 / e-ISSN 2335-8947
Zemdirbyste-Agriculture, vol. 103, No. 2 (2016), p. 135–142
The influence of primary soil tillage, deep loosening and organic fertilizers on weed incidence in crops
Regina SKUODIENĖ, Danutė KARČAUSKIENĖ, Regina REPŠIENĖ
Little is known about the influence of deep loosening and its combination with primary soil tillage and organic fertilizers on weed incidence in crops. The aim of the study was to determine the influence of different soil tillage methods and their combinations with deep loosening and organic fertilizers on the weed incidence in a crop rotation. An experiment was carried out at Vėžaičiai Branch of Lithuanian Research Centre for Agriculture and Forestry during the period 2012–2015 in a four-course crop rotation: winter wheat → spring rape → spring barley with undersown red clover → red clover. The soil of the experimental site is Dystri-Epihypogleyic Albeluvisol (ABg-p-w-dy) with a sandy loam texture.
Soil tillage methods (conventional ploughing, shallow ploughing, shallow ploughless tillage), organic fertilizers (without organic fertilizers, straw, green manure 1st cut + straw, green manure 2nd cut + straw, farmyard manure 40 t ha-1 + straw) and deep loosening impact on weed incidence was very unequal during the experimental years and depended on plant growth and development conditions.
In all experimental years, primary tillage had the main influence on the examined indicators of weed incidence (weed number and dry mass). Significantly greater number and mass of weeds were established in shallow ploughed soil. Organic fertilizers did not have any significant influence on the indicators of weed incidence; however, the use of red clover of the first cut for green manure tended to reduce weed number in the crops of the rotation during the first half of the plant growing season. A significant influence of a onetime deep loosening was observed in the first year. After improving soil aeration and humidity conditions, weed number and dry mass were significantly greater, compared to unloosened plots. The interaction between deep loosening and soil tillage methods had a great effect as well. Having used deep loosening in shallow ploughless tillage treatments, the weed number was greater compared to deeply ploughed soil.
Key words: primary soil tillage, soil fertility maintenance measures, weed number and mass.
Full text: 103_2_str18.pdf