Deng Sufeng, Huang Binbin, Zeng Bin, Cao Sheng, Gong Biya, Liao Wei, Zhang Wen, Luo Sainan, Yang Shuizhi
Hunan Horticultural Research Institute, Yuelushan Laboratory, Changsha, China.
Hunan Provincial Engineering and Technology Research Center for Agricultural Microbiology Application, Hunan Institute of Microbiology, Yuelushan Laboratory, Changsha, China.
Front Plant Sci. 2025 Aug 28;16:1560550. doi: 10.3389/fpls.2025.1560550. eCollection 2025.
Intercropping leguminous green manure in orchards represents a widely adopted agroecological practice that concurrently influences soil physicochemical properties, microbial communities, and crop performance. However, the temporal mechanisms by which different durations of soybean green manure (SGM) intercropping regulate soil-plant-microbe interactions remain insufficiently understood. This study elucidates the impact of SGM intercropping duration on ecosystem functionality in citrus orchards.
A multi-year field experiment compared SGM intercropping durations (0-, 1-, and 2-year treatments). We assessed citrus fruit quality parameters (total soluble solids, TSS; sugar-acid ratio, TSS/TA) and soil properties (pH, available nitrogen, total nitrogen, available phosphorus, available potassium, and organic matter). Microbial community structure was analyzed via high-throughput sequencing. Spearman correlation analysis (|| ≥ 0.8, < 0.05) delineated networks among intercropping duration, soil parameters, keystone microbial taxa (e.g., Proteobacteria, Acidobacteriota, Ascomycota), and fruit quality indicators.
The two-year intercropping treatment (T2) significantly enhanced fruit quality: TSS increased by 11.66% and the sugar-acid ratio (TSS/TA) by 41.95% ( < 0.05). Soil properties improved markedly: pH rose by 0.42 units, while AN, TN, AP, AK, and OM increased by 41.80%, 9.15%, 16.78%, 100.50%, and 79.53%, respectively ( < 0.05). Microbial communities underwent structural reorganization, exhibiting increased α-diversity, enhanced network complexity, and selective enrichment of beneficial taxa including Actinobacteria, Mortierellales, and Ascomycota. Correlation networks revealed significant associations among intercropping duration, soil parameters, keystone microbes, and fruit quality.
This study demonstrates that SGM intercropping enhances fruit quality through dual mechanisms: (1) amelioration of soil properties (pH elevation and improved nutrient availability), and (2) functional restructuring of microbial communities. Notably, specific taxa such as Actinobacteria play pivotal roles in nutrient cycling. Our findings provide empirical evidence for microbiome-mediated optimization of soil functionality, offering a sustainable rehabilitation strategy for degraded orchards and reinforcing the scientific value of ecological intensification in perennial cropping systems.
在果园间作豆科绿肥是一种广泛采用的农业生态实践，它同时影响土壤理化性质、微生物群落和作物表现。然而，不同时长的大豆绿肥（SGM）间作对土壤-植物-微生物相互作用的时间机制仍未得到充分理解。本研究阐明了SGM间作时长对柑橘果园生态系统功能的影响。
一项多年田间试验比较了SGM间作时长（0年、1年和2年处理）。我们评估了柑橘果实品质参数（总可溶性固形物，TSS；糖酸比，TSS/TA）和土壤性质（pH值、有效氮、总氮、有效磷、有效钾和有机质）。通过高通量测序分析微生物群落结构。Spearman相关性分析（||≥0.8，<0.05）描绘了间作时长、土壤参数、关键微生物类群（如变形菌门、酸杆菌门、子囊菌门）和果实品质指标之间的网络关系。
两年间作处理（T2）显著提高了果实品质：TSS增加了11.66%，糖酸比（TSS/TA）增加了41.95%（<0.05）。土壤性质显著改善：pH值上升了0.42个单位，有效氮、总氮、有效磷、有效钾和有机质分别增加了41.80%、9.15%、16.78%、100.50%和79.53%（<0.05）。微生物群落发生了结构重组，表现为α多样性增加、网络复杂性增强以及包括放线菌门、被孢霉目和子囊菌门在内的有益类群选择性富集。相关性网络揭示了间作时长、土壤参数、关键微生物和果实品质之间的显著关联。
本研究表明，SGM间作通过双重机制提高果实品质：（1）改善土壤性质（提高pH值和养分有效性），以及（2）微生物群落的功能重组。值得注意的是，放线菌门等特定类群在养分循环中起关键作用。我们的研究结果为微生物群落介导的土壤功能优化提供了实证依据，为退化果园提供了一种可持续的恢复策略，并强化了多年生作物系统中生态集约化的科学价值。
