Long-term effects of liming on crop yield, plant diseases, soil structure and risk of phosphorus leaching

This study examined the long-term effects of applying structure lime (mixture of ~80% CaCO3 and 20% Ca(OH)2) and ground limestone (CaCO3) on soil aggregate stability and risk of phosphorus (P) losses 5–7 years after liming, incidence of soil-borne diseases and yield in winter wheat (Tritium aestivum), oilseed rape (Brassica napus) and sugar beet (Beta vulgaris). Lime was applied in 13 field trials in Sweden 2013–2015 and soil characteristics and crop yield were monitored until 2021. Seedbed (0–4 cm depth) aggregate (2–5 mm size) stability was improved to the same extent with both lime treatments compared to the untreated control, sampled 5–7 years after liming. Analyses and estimations of different P fractions (total P, PO4-P, and particulate P) in leachate following simulated rainfall events on undisturbed topsoil cores sampled 6–8 years after liming revealed lower total P and particulate P concentrations in both lime treatments compared to the untreated control. Two sugar beet trial sites with soil pH ≤7.2 before liming showed an increase in sugar yield for structure lime and ground limestone as an effect of increased concentration of soil potassium (K-AL) and/or lower Aphanomyces root rot potential compared to the untreated control. The yield of winter wheat was not affected by the application of either type of lime at sites with pH >7.2 but the yield of oilseed rape decreased after the application of structure lime.