Crop rotation and tillage impact yield performance of soybean, sorghum, and wheat

The benefits of no-till to crop yield depend on environment and crop sequence; thus, understanding their interactions is a long-term process. This 44-year field experiment examined grain yield, yield stability, and adaptability of continuous winter wheat (Triticum aestivum L.) (Ct-WT), continuous soybean [Glycine max (L.) Merrill] (Ct-SY), continuous grain sorghum [Sorghum bicolor (L.) Moench] (Ct-GS), soybean-winter wheat rotation (SY-WT), and soybean-grain sorghum rotation (SY-GS) under three tillage systems (NT, no-tillage; RT, reduced tillage; CT, conventional tillage) near Ashland Bottoms, KS. The temporal variation across the studied years allowed us to evaluate treatments under low- and high-yielding environments. Crop rotation consistently outyielded continuous cropping, and the advantage was enhanced when integrated with NT. Yield stability decreased under NT continuous cropping in most systems. Wheat was adaptable to low- and high-yielding environments with similar grain yield and yield stability among treatments, except for NT Ct-WT, which had the lowest yield stability and grain yield (2.5 vs. 3.5 Mg ha(-1)). Soybean grain yield was greater under rotation than Ct-SY (2.7 vs. 2.0 Mg ha(-1)) and under NT than RT and CT (2.6 vs. 2.4 Mg ha(-1)), with similar yield stability. Soybean grown after wheat was more adaptable to low-yielding environments and grown after sorghum to high-yielding environments. Sorghum in NT SY-GS was adaptable to low- and high-yielding environments and had the greatest yield (6.2 Mg ha(-1)) and yield stability. This long-term study demonstrated the advantages of crop rotation combined with NT on grain yield, yield stability, and crop adaptability.