Assessing 16 Years of Tillage Dynamics on Soil Physical Properties, Crop Root Growth and Yield in an Endocalcic Chernozem Soil in Hungary

The conservation tillage method is a more holistic method introduced in Hungary two decades ago. Its environmental benefits in agriculture were widely studied and documented. The impact of conservation tillage on soil compaction and penetration resistance remains debated, necessitating further research to clarify its long-term effects in different soil types and cropping systems. The present study evaluates the impact on soil penetration resistance following 16 years of implementation of six distinct tillage practices. The study was conducted at Józsefmajor Experimental and Training Farm (JM) of the Hungarian University of Agriculture and Life Sciences near Hatvan. The study employed a randomized complete block design (RCBD) to evaluate six distinct tillage methods. These methods encompassed disking (D) at 12–14 cm depth, shallow cultivation (SC) at 18–20 cm depth, no-tilling (NT), deep cultivation (DC) at 22–25 cm depth, loosening (L) at 40–45 cm depth, and plowing (P) at 28–30 cm depth. In this study, soil compaction was assessed by measuring soil penetration resistance (SPR) at different depths (0–50 cm) and periods of the cropping year. Disking and NT significantly increased SPR between 10 and 20 cm, likely due to increased soil densification and reduced porosity in the absence of deep soil disturbance. While under sunflower cropping season significantly higher SPR was measured. In March 2021, the SPR at D and NT differed significantly from other measurement dates (September, October, November, and April). Regarding the difference between the depths, SPR increased with increasing depths in all treatment plots. The study findings revealed that NT and D tillage methods significantly increased soil penetration resistance in both cropping years, whereas L and P reduced SPR and enhanced the soil moisture storage potential of the soil particularly for the sunflower cropping period. The significance of the Spearman correlations observed suggested that SPR could be a valuable indicator of root growth potential under certain tillage conditions. Based on our results, we recommend the adoption of occasional deep soil loosening for reduced tillage systems (SC, D, DC, and NT) for both wheat and sunflower. This will create a compact-free zone for greater crop root proliferation, nutrient access, and SMC storage.