Straw Incorporation Management Affects Maize Grain Yield through Regulating Nitrogen Uptake, Water Use Efficiency, and Root Distribution

Abstract

Returning crop straw to soil can potentially improve soil health and crop production, facilitating sustainable agriculture. However, the effects of straw incorporation with various tillage management techniques combined with nitrogen (N) regimes on crop root growth, and water and N utility are not well understood. In this study, rotary tillage (RTS) and plow tillage (PTS) for straw incorporation combined with N regimes (CK, no N applied; LN, 112 kg N ha−1; MN, 187 kg N ha−1; and HN, 262 kg N ha−1) were used to determine their effects on soil water and mineral N availability, root distribution, crop N uptake, grain yield, and water use efficiency (WUE) of maize in northeast China. The results demonstrate that higher levels of pre-sowing soil-water storage and field evapotranspiration (ET), and lower levels of WUE and pre-sowing soil mineral N storage (Nmin-PS) at a depth of 0–60 cm were obtained with the RTS treatments as compared to the PTS treatments. N addition improved Nmin-PS and post-harvest soil mineral N storage (Nmin-PH) at a depth of 60–100 cm in 2016, and increased WUE compared to CK. RTS treatments enhanced root weight density (RWD) at a depth of 0–60 cm in 2016–2017, root length density (RLD), ratio of root length density (RLDR), and ratio of root weight density (RWDR) at a depth of 30–60 cm in 2016, and RLD at a depth of 0–30 cm in 2017. N addition promoted RLD and RWD at a depth of 0–10 cm in 2016–2017. RTS treatments reduced pre-silking shoot N uptake (NPS) and grain yield. Shoot N uptake and grain yield were enhanced in response to increasing levels of N; however, the grain yield did not show further significant improvements when the amount of N applied was over 187 kg N ha−1 (except for RTS in 2016). Overall, tillage with straw incorporation management and N levels markedly affected the soil physicochemical properties (such as ET, Nmin-PS, and Nmin-PH). This influenced grain yield indirectly by further mediating root traits (RLD, RWD, RLDR, and RWDR) with consequences for the NPS and post-silking shoot N uptake (NPOS) of maize, which were found to have greatest direct and positive impact on maize grain yield.

Tillage with straw incorporation reduces the optimal nitrogen rate for maize production by affecting crop uptake, utility efficiency, and the soil balance of nitrogen

“…Rotary tillage may have enhanced water and N utilization during relatively dry years and periods, improved crop growth, and increased N uptake during the growing season and may account for the higher grain yield (Rasmussen, 1999). In contrast, plough tillage increased the soil water holding capacity by improving soil porosity and rainfall interception during wet years, enhanced water layer storage and deep distribution, promote deep root growth and nutrient uptake, and increased grain yield (Mu et al, 2016; Sui et al, 2020).…”

Soil properties and microbial communities of spring maize filed in response to tillage with straw incorporation and nitrogen fertilization in northeast China

“…The three N fertilization levels were: 0 kg N ha –1 (control, CK), 187 kg N ha –1 (medium N application, MN) and 337 kg N ha –1 (high N application, HN) and were applied to the subplots. We designed five different nitrogen fertilizer gradients including 0, 112, 187, 262 and 337 kg N ha −1 , it has been found in previous studies that maize grain yield would not increase significantly when N application more than 187 kg N ha −1 ( Sui et al, 2020 ). Therefore, we chose 0, 187 and 337 kg N ha −1 in this research, represently.…”

Effects of Combined Long-Term Straw Return and Nitrogen Fertilization on Wheat Productivity and Soil Properties in the Wheat-Maize-Soybean Rotation System in the Pannonian Plain

“…According to our estimation, at present, about 40% of crop residues are returned to the soil every year in Serbia. Straw return, as a sustainable agricultural practice, is widely applied to improve crop yields and soil quality [19][20][21][22], while it can also contribute to increased yield stability [23][24][25]. In the conditions of the Vojvodina chernozem, [12,26,27] reported the positive effects of plowing crop residues with the application of appropriate amounts of nitrogen on wheat and maize yields.…”

“…The SOC regulates physical, chemical, and biological properties of the soil [52,53], and therefore, its content is closely related to the soil quality and productivity [54,55]. Straw return can promote root growth, reduce evaporation, increase soil water storage capacity, and create appropriate soil moisture conditions for crop growth, thereby increasing yield [11,22,[56][57][58]. However, if the amount of returned straw is too high, the relatively high C/N ratio can stimulate N absorption by microorganisms and reduce the amount of mineral N available for plant growth and development [59].…”