Fig 1.
General location and climatic parameters of three sampling sites.
Three randomly selected areas where Elymus nutans Griseb was growing vigorously. The map, base map, shape files, and map data were obtained from the National Geographic Information Public Service Platform “TianDiTu” (https://cloudcenter.tianditu.gov.cn/dataSource), the specific URL of the web page for retrieving this data is: https://cloudcenter.tianditu.gov.cn/administrativeDivision/. The map base layer has been reviewed and approved with the approval number GS (2024) 0650. The base map is unmodified.
Table 1.
Growth promoting characteristics of five PGPR strains.
Fig 2.
The effects of different treatments on the growth of EnG at different temperatures.
T1(addition of PGPR but no addition of NPK fertilizers), T2 (neither PGPR nor NPK fertilizers), T3 (addition of PGPR and NPK fertilizers), and T4 (no addition of PGPR but addition of NPK fertilizers).
Fig 3.
Effect of different treatments on plant height (PT), dry weight (DW), and plant chlorophyll (Chl)content.
Lowercase letters indicate differences between treatments and uppercase letters indicate differences between temperatures.
Fig 4.
Effect of different treatments on root length (RL), number of root branches (RB), root surface area (RSA), and root average diameter (RD).
Lowercase letters indicate differences between treatments and uppercase letters indicate differences between temperatures.
Fig 5.
Effect of different treatments on soluble sugars (SS), and soluble proteins (SP)content.
Lowercase letters indicate differences between treatments and uppercase letters indicate differences between temperatures.
Fig 6.
Effect of different treatments (T3 and T4) on nutrient utilization.
Physiological efficiency of nitrogen (NPE), phosphorus (PPE), potassium (KPE), agronomic efficiency of nitrogen (NAE), phosphorus (PAE) and potassium (KAE), and apparent recovery efficiency of nitrogen (NRE), phosphorus (PRE) and potassium (KRE) content. * means p < 0.05, ** means p < 0.01, *** means p < 0.001, ns means no significant difference.
Table 2.
The main effects of temperature (T), PGPR, and fertilizers (NPK) on Elymus nutans Griseb.
Fig 7.
Relationship between plant growth factors and nutrient utilization.
(a) Spearman’s correlation between the relative abundance of PE, AE, and RE, and Plant growth factors. *, **, and *** represent significant correlations at the 0.05, 0.01, and 0.001 levels. (b) Mantel test between nutrient utilization and indicators of plant growth. In Figure (a), the thickness and color of the lines are indicated by Mantel’s p/r values, illustrating the degree of correlation’s significance and intensity. Figure (b) employs a heatmap, where the color gradient communicates that blue denotes a positive correlation, whereas red indicates a negative one. PT, plant height; DW, dry weight; Chl, plant chlorophyll; RL, root length; RB, number of root branches; RSA, root surface area; RD, root average diameter; SS, soluble sugars; SP, soluble proteins.