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

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