Response of crops yield to long-term reduced soil tillage and direct sowing

Abstract

Many short-term field experiments worldwide are done to investigate reduced soil tillage but only limited number long-term ones. The effect of short- term and long-term reduced tillage and direct sowing on crops can be different. The aim of our investigation was to study response of several crops yield within 15 years period to application of long-term reduced soil tillage and direct sowing. Field experiment was set up at Experimental Station of Aleksandras Stulginskis University (at that time Lithuanian Agricultural Academy) in 1988 and modified in 2001. Soil of the experimental site – Endohypogleyic-Eutric Planosol – Ple-gln-w. Soil texture – medium loam on sandy loam over the moraine clay. The effect of following five treatments was investigated: conventional ploughing at 23-25 cm depth (CP), shallow ploughing at 12-14 cm depth (SP), deep chiselling at 23-25 cm depth (DC), shallow chiselling at 12-14 cm depth (SC), direct sowing (DS). Crop rotation in the experiment: 1) spring rape, 2) spring wheat (2001-2003) and winter wheat (from 2004), 3) sugar beet (2001-2007) and maize (from 2008), 4) spring barley. During fifteen year period (2001-2015) cumulative spring rape seed yield was higher when reduced tillage and direct sowing were applied as compared with that where soil was conventionally ploughed. This yield increase was not significant – in average up to 0.10 t ha-1 per year. Reduced tillage had no negative influence on cumulative spring and winter wheat yield until 2010