Luo Xiulan, Wang Dewei, Liu Yuting, Qiu Yuanze, Zheng Junlin, Xia Guimin, Elbeltagi Ahmed, Chi Daocai
College of Water Conservancy, Shenyang Agricultural University, Shenyang, China.
College of Mechanical and Electrical Engineering, Tarim University, Alar, China.
Front Plant Sci. 2024 Oct 22;15:1459751. doi: 10.3389/fpls.2024.1459751. eCollection 2024.
Peanut production is being increasingly threatened by water stress with the context of global climate change. Film mulching have been reported to alleviate the adverse impact of drought on peanut. Lower phosphorus use efficiency is another key factor limiting peanut yield. Application of iron-modified and phosphorus-loaded biochar (B) has been validated to enhance phosphorus utilization efficiency in crops. However, whether combined effect of film mulching and B could increase water use efficiency and enhance peanut production through regulating soil properties and root morphologies needs further investigation.
A two-year (2021-2022) pot experiment using a split-plot design was conducted to investigate the effects of phosphorus fertilizer substitution using B on soil properties, root morphology, pod yield, and water use of peanut under film mulching. The main plots were two mulching methods, including no mulching (M0) and film mulching (M1). The subplots were four combined applications of phosphorus fertilizer with B, including conventional phosphorus fertilizer rates (PCR) without B, P1C0; 3/4 PCR with 7.5 t ha B, P2C1; 3/4 PCR with 15 t ha B, P2C2; 2/3 PCR with 7.5 t ha B, P3C1; 2/3 PCR with 15 t ha B, P3C2.
The results indicated that regardless of biochar amendments, compared with M0, M1 increased soil organic matter and root morphology of peanut at different growth stages in both years. In addition, M1 increased peanut yield and water use efficiency (WUE) by 18.8% and 51.6%, respectively, but decreased water consumption by 25.0%, compared to M0 (two-year average). Irrespective of film mulching, P2C1 increased length, surface area, and volume of peanut root at seedling by 16.7%, 17.7%, and 18.6%, at flowering by 6.6%, 19.9%, and 29.5%, at pod setting by 22.9%, 33.8%, and 37.3%, and at pod filling by 48.3%, 9.5%, and 38.2%, respectively (two-year average), increased soil pH and organic matter content during peanut growing season, and increased soil CEC at harvest. In general, the M1P2C1 treatment obtained the optimal root morphology, soil chemical properties, WUE, and peanut yield, which increased peanut yield by 33.2% compared to M0P1C0. In conclusion, the combination of film mulching with 7.5 t ha B (M1P2C1) effectively improved soil chemical properties, enhanced root morphology of peanut, and ultimately increased peanut yield and WUE.
在全球气候变化背景下，花生生产正日益受到水分胁迫的威胁。据报道，地膜覆盖可减轻干旱对花生的不利影响。较低的磷利用效率是限制花生产量的另一个关键因素。施用铁改性和富磷生物炭（B）已被证实可提高作物对磷的利用效率。然而，地膜覆盖和生物炭的联合效应是否能通过调节土壤性质和根系形态来提高水分利用效率并增加花生产量，还需要进一步研究。
采用裂区设计进行了为期两年（2021 - 2022年）的盆栽试验，以研究在覆膜条件下，用生物炭替代磷肥对花生土壤性质、根系形态、荚果产量和水分利用的影响。主区为两种覆盖方式，包括不覆盖（M0）和地膜覆盖（M1）。副区为磷肥与生物炭的四种联合施用方式，包括不施生物炭的常规磷肥用量（PCR），P1C0；3/4 PCR + 7.5 t·ha生物炭，P2C1；3/4 PCR + 15 t·ha生物炭，P2C2；2/3 PCR + 7.5 t·ha生物炭，P3C1；2/3 PCR + 15 t·ha生物炭，P3C2。
结果表明，无论生物炭添加情况如何，与M0相比，M1在两年中均增加了不同生长阶段花生的土壤有机质和根系形态。此外，与M0相比（两年平均值），M1使花生产量和水分利用效率（WUE）分别提高了18.8%和51.6%，但耗水量降低了25.0%。无论是否覆膜，P2C1使花生苗期根系长度、表面积和体积分别增加了16.7%、17.7%和18.6%，花期分别增加了6.6%、19.9%和29.5%，结荚期分别增加了22.9%、33.8%和37.3%，饱果期分别增加了48.3%、9.5%和38.2%（两年平均值），增加了花生生长季土壤pH值和有机质含量，并在收获时增加了土壤阳离子交换量。总体而言，M1P2C1处理获得了最佳的根系形态、土壤化学性质、WUE和花生产量，与M0P1C0相比，花生产量提高了33.2%。综上所述，地膜覆盖与7.5 t·ha生物炭（M1P2C1）相结合有效地改善了土壤化学性质，增强了花生根系形态，最终提高了花生产量和WUE。
