Effects of straw returning and potassium fertilizer application on root characteristics and yield of spring maize in China inner Mongolia

Abstract

AbstractExploring the effects of straw return (ST) and potassium fertilizer on soil structure, spring maize (Zea mays L.) root growth, K‐absorption efficiency and yield is essential for devising optimized straw return and potassium fertilizer management practices to increase grain yield for food security. In this study, two straw return levels used were straw return , no straw return and two potassium application levels used were 6K (90 kg/ha potassium application), no potassium (0K). Analyzed the effects of the above four treatments on soil structure, spring maize root indicators, K‐absorption efficiency and yield in three ecological regions in two years. The results showed that the effect of straw return on soil structure and root growth was better than that of applying potassium fertilizer. The effect of potassium fertilizer application on maize grain yield and K‐absorption efficiency was better than that of straw return. The impact of the interaction was better than straw return or the application potassium fertilizer alone. Straw return improved the effects of potassium fertilizer on soil bulk density, soil porosity, spring maize root length, root surface area, root volume, maize grain K‐absorption efficiency and yield by 3.99%–7.27%, 3.89%–7.40%, 1.35%–71.01%, 19.16%–42.45%, 10.49%–22.73%, 13.57%–19.67% and 4.43%–7.05%, respectively. Therefore, the interaction of straw return and potassium fertilizer was the best measure to maintain high and stable maize yield, increasing K‐absorption efficiency and improving the nutrient resource management of straw and potassium fertilizer, which was appropriate for spring maize planting.