Huang Jie, Wang Xinyue, Yang Lili, Li Yuanhuan, Xia Bing, Li Hailin, Deng Xiaohua
College of Agriculture, Hunan Agricultural University, Changsha, China.
College of Plant Science and Technology, Hunan Biological and Electromechanical Polytechnic, Changsha, China.
Front Plant Sci. 2025 Jun 13;16:1552955. doi: 10.3389/fpls.2025.1552955. eCollection 2025.
Organic amendments supply essential nutrients to crops and act as effective soil conditioners. This study investigates the effects and mechanisms of organic amendments on soil physicochemical properties and microbial diversity, aiming to provide technical solutions for alleviating continuous cropping obstacles. A three-year field experiment was conducted with four types of organic amendments: biological organic fertilizer (BF), carbon-polymerized organic water-soluble fertilizer (CF), potassium fulvate from mineral sources (PF), and microbial fertilizer (MF). The control group received no organic fertilizer application. Results showed that compared to the control, organic amendments significantly increased soil organic matter and available nutrient contents, organic matter and available phosphorus under BF (22.5 and 43.2 mg/kg, respectively) showed increases of 129.6% and 53.7%, respectively. Similarly, available potassium in PF (286.6mg/kg) was elevated by 47.3%. Additionally, soil pH was increased (shifting from 5.4 to 6.0), thereby alleviating soil acidification. 16S rRNA and ITS sequencing revealed that organic amendments markedly influenced soil microbial abundance and diversity, increasing the relative abundance of beneficial bacteria (e.g., The abundance of rose from 10.0% in control to 19.2% in MF.) while suppressing pathogenic bacteria (e.g., The abundance of decreased from 10.5% in control to 2.5% in MF.). In terms of tobacco growth, organic amendments enhanced root length, surface area, volume, and branching number; Significant increases were observed in α-amylase activity (from 0.6 to 1.6 mg/min/g)) and nitrate reductase activity (from 0.15 to 0.21 U/g) in leaves following the treatment.; and reduced the incidence of bacterial wilt and black shank diseases. Specifically, BF, CF, PF, and MF achieved relative control efficacies of 66.7%, 56.0%, 44.0%, and 61.9% against bacterial wilt, and 66.0%, 52.6%, 42.3%, and 55.7% against black shank, respectively. In conclusion, the application of organic amendments can alleviate continuous cropping barriers by improving the soil micro-environment, promoting tobacco growth, and providing certain control over soil-borne diseases. Overall, the BF treatment showed the most comprehensive improvement effect, and to a lesser extent, PF and MF.
有机改良剂为作物提供必需养分，并作为有效的土壤改良剂。本研究调查了有机改良剂对土壤理化性质和微生物多样性的影响及作用机制，旨在为缓解连作障碍提供技术解决方案。进行了为期三年的田间试验，使用了四种有机改良剂：生物有机肥（BF）、碳聚合有机水溶性肥料（CF）、矿物源黄腐酸钾（PF）和微生物肥料（MF）。对照组不施用有机肥料。结果表明，与对照相比，有机改良剂显著增加了土壤有机质和有效养分含量，BF处理下的有机质和有效磷（分别为22.5和43.2mg/kg）分别增加了129.6%和53.7%。同样，PF中的有效钾（286.6mg/kg）提高了47.3%。此外，土壤pH值升高（从5.4变为6.0），从而缓解了土壤酸化。16S rRNA和ITS测序表明，有机改良剂显著影响土壤微生物丰度和多样性，增加了有益细菌的相对丰度（例如， 的丰度从对照中的10.0%上升到MF中的19.2%），同时抑制了病原菌（例如， 的丰度从对照中的%下降到MF中的2.5%）。在烟草生长方面，有机改良剂增加了根长、表面积、体积和分支数；处理后叶片中的α-淀粉酶活性（从0.6提高到1.6mg/min/g）和硝酸还原酶活性（从0.15提高到0.21U/g）显著增加；并降低了青枯病和黑胫病的发病率。具体而言，BF、CF、PF和MF对青枯病的相对防效分别为66.7%、56.0%、44.0%和61.9%，对黑胫病的相对防效分别为66.0%、52.6%、42.3%和55.7%。总之，施用有机改良剂可以通过改善土壤微环境、促进烟草生长以及对土传病害提供一定防治来缓解连作障碍。总体而言，BF处理的综合改善效果最佳，PF和MF的效果次之。
