Abstract:

Modern agriculture confronts the dual challenge of suboptimal nutrient use efficiency (NUE) and the escalating chain of environmental burdens. These include increased greenhouse gas emissions, widespread soil degradation, and rising water eutrophication due to excessive fertilizer runoff. In this context, the rhizosphere microbiome, an indispensable symbiotic partner to plants throughout their life cycle, has been shown to critically regulate the transformation, mobilization, and supply of key soil nutrients. This occurs through core ecological mechanisms such as associative nitrogen fixation (e.g., performed by genera including Azospirillum), organic acid secretion-mediated dissolution of insoluble phosphorus (as commonly observed in Pseudomonas), and siderophore-chelated iron mobilization, which enhance nutrient accessibility for plant uptake. Recent breakthroughs in synthetic biology have significantly advanced the engineering of stable and efficient Synthetic Microbial Communities (SynComs), propelling this approach into a burgeoning frontier of agricultural biotechnology. SynComs integrate functionally diverse microbial strains to overcome well-documented limitations of single-strain inoculants, such as inconsistent performance and low resilience under field conditions. These designed communities form more stable and robust functional modules within the rhizosphere, leading to improved nutrient cycling and root system health. Beyond their application as agronomic biofertilizers, SynComs also serve as a powerful toolset for deciphering complex microbe-microbe interactions and elucidating synergistic mechanisms between microorganisms and host plants. Despite the considerable promise of SynComs technology, several critical barriers impede its real-world deployment. These include poor colonization stability of artificially constructed communities, limited environmental adaptability across varying agroecosystems with divergent soil properties and climatic conditions, and an insufficient mechanistic understanding of multi-trophic plant-microbe interactions. Additionally, commercialization faces further challenges due to prohibitive costs linked to large-scale production, formulation, and field application, as well as undefined long-term ecological risks such as potential disruption of native microbial communities or horizontal gene transfer. To realize the full potential of SynComs, coordinated multidisciplinary efforts are essential. Research should focus on engineering adaptively intelligent consortia capable of responding to dynamic environmental conditions, creating field-applicable tools for real-time monitoring and precision regulation, advancing scalable deployment strategies amenable to existing farming systems, and establishing rigorous ecological risk assessment protocols. An in-depth understanding of rhizosphere microbiome functions, coupled with the active development of SynCom technologies, represents a pivotal opportunity to address pressing agricultural nutrient management challenges. Such advances can significantly reduce inputs of synthetic fertilizers while enhancing nutrient use efficiency, ultimately promoting a transition toward resource-efficient and ecologically sustainable agricultural systems. Collectively, these efforts posses theoretical value and substantial industrial potential.

Key words: rhizosphere microbiome, synthetic biology, nutrient absorption and utilization, gene editing technology, synthetic microbial community

摘要：

现代农业发展正面临养分利用效率低下和环境负担持续加剧的双重挑战。近年研究表明，根际微生物组（rhizosphere microbiome）作为植物的“第二基因组”，通过调控土壤氮、磷、铁等关键养分的生物地球化学循环，在植物高效获取养分过程中发挥核心驱动作用。合成生物学（synthetic biology）的快速发展为根际微生物组的精准解析与功能设计提供了创新性工具，通过模块化基因编辑、人工群落构建及宿主-微生物互作调控等策略显著提升植物养分利用效率，为突破传统农业依赖化肥、缓解资源浪费和环境压力提供全新的技术途径。本文系统综述了合成生物学驱动下根际微生物组工程在植物养分高效利用领域的研究进展，重点包括根际微生物组参与土壤养分循环的作用机制解析，合成生物学工具在单菌功能强化，群落协同调控、宿主-微生物互作优化等方面的关键作用以及当前技术发展中面临的微生物组复杂性限制、工程菌田间定植稳定性不足、跨作物普适性受限和潜在生态安全风险等诸多瓶颈。并展望了合成微生物组在可持续农业发展中的应用潜力，未来通过定向功能设计、智能响应系统构建及“植物-微生物-环境”协同调控，有望实现作物养分利用效率与可持续生产力的显著提升，从而为推动农业绿色转型提供关键科学技术支撑。

关键词: 根际微生物组, 合成生物学, 养分吸收利用, 基因编辑技术, 人工合成菌群