Khan Zaid, Zhang Kangkang, Khan Mohammad Nauman, Bi Junguo, Zhu Kunmiao, Luo Lijun, Hu Liyong
MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China.
Shanghai Agrobiological Gene Center, Shanghai, China.
Front Plant Sci. 2022 Mar 10;13:853449. doi: 10.3389/fpls.2022.853449. eCollection 2022.
The amendment of biochar has been proposed to improve soil fertility and crop yield. However, consolidated information lacks explaining the role of biochar on soil and plant enzymatic activities involved in nutrients cycling in soil and accumulation in plants improving utilization of applied inorganic fertilizer and crop growth. In the current study, we evaluated the integral effects of biochar levels (B0:0, B15:15, B3:30, and B60:60 t ha) and nitrogen fertilizer levels (N0:0, N75:75, N225:225, and N450:450 kg ha) on soil physicochemical properties, enzymatic activities, nitrogen use efficiency (NUE) and grain yield of rapeseed for 2 years in the pots during 2020 and 2021. The findings revealed that compared to control (B0 + N0), a combination of B30 + N450 increased soil urease activity by 73 and 75%, and B60 + N450 increased activities of soil catalase by 17 and 16%, and B60 + N225 increased alkaline phosphatase by 17 and 19%, respectively, in the first and second year. Moreover, a single application of high nitrogen at 450 kg ha reduced the activities of plant nitrogen metabolism-related enzymes, however; the integration of biochar at 30 t ha compensated the high nitrogen toxicity and improved the activities of nitrate reductase (NR), nitrite reductase NIR, glutamate synthase (GS) and glutamine synthetase (GOGAT) at seedling stage (SS) and flowering stage (FS) in both years. The integration of biochar at 30 t ha with nitrogen at 450 kg ha induced synergetic effects on rapeseed growth through sorption of excessive nitrogen in soil and significantly improved the plant height up to 11 and 18%, pods plant 39 and 32% and grain yield plant 54 and 64%, respectively, during the first and second year. Moreover, biochar at 15 t ha along with nitrogen at 225 kg ha resulted in the highest NUE of 29% in both years suggesting that biochar can also offset the deficiency of lower nitrogen. This study highlighted the ameliorative effect of biochar suppressing high nitrogen toxicity and decreasing lower nitrogen deficiency effects on rapeseed growth by improving nitrogen use efficiency via enhancing soil conditions, enzymatic activities and soil nitrogen utilization potential and thus improving rapeseed growth and yield.
有人提出施用生物炭来提高土壤肥力和作物产量。然而，目前还缺乏综合信息来解释生物炭在参与土壤养分循环和植物养分积累、提高无机肥料利用率及促进作物生长的土壤和植物酶活性方面所起的作用。在本研究中，我们评估了2020年和2021年两年间，生物炭施用量水平（B0:0、B15:15、B30:30和B60:60 t/ha）和氮肥施用量水平（N0:0、N75:75、N225:225和N450:450 kg/ha）对盆栽油菜土壤理化性质、酶活性、氮素利用效率（NUE）和籽粒产量的综合影响。研究结果表明，与对照（B0 + N0）相比，在第一年和第二年，B30 + N450组合使土壤脲酶活性分别提高了73%和75%，B60 + N450使土壤过氧化氢酶活性分别提高了17%和16%，B60 + N225使碱性磷酸酶活性分别提高了17%和19%。此外，单施450 kg/ha高氮会降低植物氮代谢相关酶的活性；然而，30 t/ha生物炭与高氮配合施用可补偿高氮毒性，并在两年的苗期（SS）和花期（FS）提高硝酸还原酶（NR）、亚硝酸还原酶（NIR）、谷氨酸合酶（GS）和谷氨酰胺合成酶（GOGAT）的活性。30 t/ha生物炭与450 kg/ha氮配合施用，通过吸附土壤中过量的氮对油菜生长产生协同效应，在第一年和第二年分别使株高显著提高11%和18%，单株荚数提高39%和32%，单株籽粒产量提高54%和64%。此外，15 t/ha生物炭与225 kg/ha氮配合施用，两年的NUE均最高，达29%，这表明生物炭还可以弥补低氮的不足。本研究强调了生物炭通过改善土壤条件、酶活性和土壤氮素利用潜力来提高氮素利用效率，从而减轻高氮毒性和低氮不足对油菜生长的影响，进而提高油菜生长和产量的改良作用。
