Abstract

Background: Grassland ecosystems, covering approximately 27% of the Earth's terrestrial area, are experiencing severe functional decline due to intensifying abiotic stresses such as drought, salinization, and heavy metal pollution under global climate change. Glycine betaine (GB) has been widely demonstrated to enhance abiotic stress tolerance in agricultural crops through mechanisms like osmotic adjustment, antioxidant defense, and photosynthetic protection. However, a significant knowledge and application gap exists between its well-established agricultural use and its potential application in native grassland restoration.

Methods: To bridge this gap, this study performed a systematic bibliometric analysis based on 295 core publications (132 from the China National Knowledge Infrastructure, CNKI, and 163 from the Web of Science Core Collection, WoS). The literature search employed tailored query strategies in both databases to capture studies on exogenous glycine betaine application in plants. Following rigorous screening to exclude irrelevant topics such as zoology or isolated organ studies, the final corpus was analyzed using VOSviewer and CiteSpace for keyword evolution, co-occurrence networks, research trajectory mapping, and collaboration pattern visualization. This approach enabled a comparative examination of global and Chinese research trends, identified structural gaps, and laid the groundwork for proposing a targeted application framework.

Results: Our analysis reveals a complementary global research landscape: international studies exhibit a " mechanism-oriented " trajectory, while Chinese research demonstrates an " application-driven " trajectory, rapidly adapting GB to diverse crops and compound stresses. A critical structural gap is identified: research is overwhelmingly concentrated on cultivated species under controlled conditions, lacking studies on keystone grassland species, field validations, and ecosystem-level assessments. To address this, we propose a novel, dynamic " Three-Phase Application Framework ": Emergency Response - Functional Restructuring - Institutional Embedding. This framework re-conceptualizes GB as an evolving agent within the socio-ecological system, transitioning from a " system initiating factor " to a " system synergist and capacity builder " and finally to " institutional knowledge ". For each phase, we delineate specific implementation pathways across technology, ecology, economy, rural communities, and urban linkages.

Conclusion: This work provides a comprehensive theoretical and practical roadmap for the targeted migration of GB technology into grassland restoration. It offers a transferable model for integrating other agriculture-derived biotechnologies into complex social-ecological systems, thereby contributing to climate-resilient ecosystem restoration and sustainable land management in dryland regions globally.