Soil physical properties and yield of flooded rice under no‑tillage

Abstract

The objective of this work was to evaluate the soil physical properties and the yield of flooded rice under no‑tillage, in the west border of Rio Grande do Sul, Brazil, compared with the conventional tillage system. The experimental design was completely randomized, with three experiments (E) and ten replicates: E1, no‑tillage after leveling (E1PDR) and conventional tillage with two harrowings at 0.0–0.07 m layer after leveling (E1C), after seven years of fallow of rice tillage, with sowing of rye grass in winter and grazing; E2, no‑tillage (E2PD) and conventional tillage (E2C), after native field; E3, no‑tillage (E3PD), no‑tillage after leveling (E3PDR), and conventional tillage (E3C) after rice under conventional tillage, during one year under native field. The soil physical properties differed little between the no‑tillage system and conventional tillage. Continued Oryza sativa tillage with irrigated rice caused soil compaction in the 0.07–0.10 m layers. The rice yield did not differ between the no‑tillage system and conventional tillage, in the experiments 1 and 2. In experiment 3, with greater amount of remaining rice straw, the yield was greater in the conventional tillage system.