Effects of Long-Term Positioning Tillage Method and Straw Management on Crop Yield and Nutrient Accumulation and Utilization in Dryland Wheat–Maize Double-Cropping System
Authors: Huang Ming , Xiao Huishu , Zhang Jun , Li Shuang , Peng Yanmin , Guo Jin-Hua , Jiang Peipei , Wang Rongrong , Chen Yushu , Li Chunxia , Wang Hezheng , Fu Guozhan , Shaaban Muhammad , Li Youjun , Wu Jinzhi , Li Guoqiang 
Published: January 2025

The tillage method and straw returning are the two most important agronomic measures for crop production, but their combined effects on nutrient accumulation and utilization and grain yield in dryland winter wheat (Triticum aestivum L., namely wheat)–summer maize (Zea mays L., namely maize) double-cropping system are still poorly understood. The present study delves into the impact of the tillage method and straw returning on yield and nutrient accumulation and utilization in wheat–maize double-cropping system based on a field split-plot positioning experiment (started in October 2009). Three tillage methods—plowing (PT, 30–35 cm in depth), rotary tillage (RT, 12–15 cm in depth), no-tillage (NT)—and two straw management—zero straw returning (S0) and straw returning (SR)—were assigned to the main plots and subplots, respectively, thus encompassing six distinct treatments of PTS0, PTSR, RTS0, RTSR, NTS0, and NTSR. The grain yield and its components; the nitrogen (N), phosphorus (P), and potassium (K) accumulation at maturity; and the internal efficiency of N, P, and K in wheat and maize from 2018 to 2022 were investigated. The results indicated that in the experimental years, tillage methods and straw management significantly affected wheat, maize, and annual yield. Compared with NT, RT significantly increased wheat yield by 9.5% and maize K accumulation by 5.8%, and PT significantly increased wheat K accumulation by 11.1% and the yield and N, P, and K accumulation of maize by 6.3%, 7.8%, 8.9%, and 5.3%. Compared with RT, PT significantly increased yield and K accumulation in wheat and yield and N and P accumulation in maize. Compared with NTSR, PTSR significantly increased the yield and N, P, and K accumulation in wheat, but it did not affect yield and nutrient accumulation in maize; RTSR significantly increased wheat yield while it significantly decreased yield and N, P, and K accumulation in maize. Compared with RTSR, PTSR significantly increased the yield and N, P, and K accumulation by 4.0%, 19.5%, 19.6%, and 7.0% in wheat, respectively, and 7.5%, 6.1%, 13.3% and 13.6% in maize. Under the same tillage method, compared with S0, SR significantly increased crop yield and N, P, and K accumulation by 2.4–25.4%, 8.5–43.3%, 12.9–37.8%, and 11.0–51.0%, but it significantly reduced wheat K internal efficiency and maize N, P, K internal efficiency. The effectiveness of straw management on crop yield and N, P, and K accumulation was greater than that of tillage methods. Therefore, the combination of plowing tillage with straw returning (PTSR) is an effective tactic to promote crop yield in dryland wheat–maize double-cropping system. This study offered insights for achieving high yield by regulating the accumulation and internal efficiency of plant N, P, and K nutrients in wheat–maize double-cropping system in drought-prone areas and environments similar to the study areas.