In the context of climate change, the frequency and intensity of extreme weather events are increasing, environmental pollution and global warming are exacerbated by anthropogenic activities, and plants will experience a more complex and variable environment of stress combinations. Research on plant responses to stress combinations is crucial for the development and utilization of climate-adaptive plants. Recently, the concept of stress combinations has been expanded from simple to multifactorial stress combinations (MFSCs). Researchers have realized the complexity and necessity of stress combination research and have extensively employed composite gradient methods, multi-omics techniques, and interdisciplinary approaches to integrate laboratory and field experiments. Researchers have studied the response mechanisms of plant reactive oxygen species (ROS), phytohormones, transcription factors (TFs), and other response mechanisms under stress combinations and reached some generalized conclusions. In this article, we focus on the research progress and methodological dynamics of plant responses to stress combinations and propose key scientific questions that are crucial to address, in the context of plant responses to stress assemblages, conserving biodiversity, and ensuring food security. We can enhance the search for universal pathways, identify targets for stress combinations, explore adaptive genetic responses, and leverage high-technology research. This is in pursuit of cultivating plants with greater tolerance to stress combinations and enabling their adaptation to and mitigation of the impacts of climate change.

Leymus chinensis is important for ecological restoration and stock farming in Eurasia. In the context of climate change, excavating L. chinensis germplasm resources with excellent ecological functional traits is important to resist grassland degradation and promote the restoration of degraded grassland ecosystems. In this study, we used 42 L. chinensis germplasm resources (LC01–LC42) from different geographical sources to perform a multidimensional comprehensive evaluation of drought tolerance, rhizome space expansion, and soil improvement abilities. (1) LC07, LC15, LC18, and LC19 exhibited excellent ecological functional traits and could be used in breeding for ecological restoration. They were mainly from eastern and central Mongolia and central Inner Mongolia. (2) Principal component analysis showed that eight principal components with eigenvalues ≥1 were extracted from 26 traits of L. chinensis. The cumulative contribution rate was 80.551%. (3) There was a significant positive correlation between the F value and longitude and a significant negative correlation of the F value with latitude. L. chinensis germplasms from high longitudes and low altitudes may exhibit better comprehensive performance. (4) Plant height, leaf number, tiller number, malonaldehyde, chlorophyll content, dry weight on the ground, maximum one-direction extended distance, and organic matter can be used as key indices to comprehensively evaluate L. chinensis germplasm resources.