Impact of Tillage and Straw Management on Soil Properties and Rice Yield in a Rice-Ratoon Rice System

Abstract

The rice-ratoon system has long been considered an important economic, time-saving, and labor-saving planting method. Optimal tillage and straw management are beneficial to increasing the growth and yield of recycled rice. However, there is little research on the physical and chemical properties of soil under tillage and straw management, and its effects on the yield and fertilizer utilization of recycled rice. A field experiment was conducted to study the effects of four types of tillage and straw management on rice yield and soil properties in central China during 2020–2021. The types of management were no-till with residues retained (NT+S); plow tillage with residue retention (PT+S); no-till with residues removed (NT-S); and plow tillage with residue removed (PT-S). Compared with PT, yield decreased by 38.8% in NT, while straw returning effectively increased the yield of regenerated rice. NT+S increased the yield of main season rice by 37.0% and ratoon rice by 45.3%. Compared with non-returning straw, straw returning increased soil total porosity, soil organic carbon, and activity of β-glucosidase and urease, among which TP and SOC were increased by 8.8% and 27.8%, respectively. The results showed that returning straw to the field could significantly reduce the yield loss caused by no-tillage and improve the soil structure. No-tillage combined with returning straw to the field of regenerative rice is a green, light, and simplified cultivation mode worthy of further exploration.