Bacteria sample information.

Nitrogen (N), phosphorus (P), and potassium (K) exert various effects on strawberry (Fragaria ananassa Duchesne) yields. In this study, we employed an orthogonal experimental design (T1-T9) with three fertilization treatments (N, P, and K) at three levels to identify an optimal fertilization scheme for strawberry cultivation. The effects of fertilizer combinations the rhizosphere soil microbial community were also explored by using bacterial full-length 16S rRNA and fungal ITS (internal transcribed spacer) sequencing (30 samples for each analysis). The results showed that the average plant height and leaf area of the fertilized groups were 24.6% and 41.6% higher than those of the non-fertilized group (T0). After 60 d of planting, the sucrase activity in the T6 group increased by 76.67% compared to the T0 group, with phosphate fertilizer exerting a more significant impact on sucrase activity. The T6 treatment group had the highest alpha diversity index among bacterial and fungal microorganisms, and had a different microbial community structure compared with the control group. The most abundant bacterial taxa in the strawberry rhizosphere soil were Proteobacteria, Bacteroidota, and Acidobacteriota, and the most abundant fungal phyla were Monoblepharomycota, Glomeromycota, and Mucoromycota. Application of the optimal combined fertilizer treatment (T6) significantly increased the abundance of Proteobacteria and altered the abundance of Gemmatimonas compared to other treatment groups. Notably, Gemmatimonas abundance positively correlated with strawberry plant height and soil N, P, and K levels. These findings indicated that the relative abundance of beneficial bacteria could be enhanced by the application of an optimal fertilizer ratio, ultimately improving strawberry agronomic traits.</div

Phenotypic correlation data.

Nitrogen (N), phosphorus (P), and potassium (K) exert various effects on strawberry (Fragaria ananassa Duchesne) yields. In this study, we employed an orthogonal experimental design (T1-T9) with three fertilization treatments (N, P, and K) at three levels to identify an optimal fertilization scheme for strawberry cultivation. The effects of fertilizer combinations the rhizosphere soil microbial community were also explored by using bacterial full-length 16S rRNA and fungal ITS (internal transcribed spacer) sequencing (30 samples for each analysis). The results showed that the average plant height and leaf area of the fertilized groups were 24.6% and 41.6% higher than those of the non-fertilized group (T0). After 60 d of planting, the sucrase activity in the T6 group increased by 76.67% compared to the T0 group, with phosphate fertilizer exerting a more significant impact on sucrase activity. The T6 treatment group had the highest alpha diversity index among bacterial and fungal microorganisms, and had a different microbial community structure compared with the control group. The most abundant bacterial taxa in the strawberry rhizosphere soil were Proteobacteria, Bacteroidota, and Acidobacteriota, and the most abundant fungal phyla were Monoblepharomycota, Glomeromycota, and Mucoromycota. Application of the optimal combined fertilizer treatment (T6) significantly increased the abundance of Proteobacteria and altered the abundance of Gemmatimonas compared to other treatment groups. Notably, Gemmatimonas abundance positively correlated with strawberry plant height and soil N, P, and K levels. These findings indicated that the relative abundance of beneficial bacteria could be enhanced by the application of an optimal fertilizer ratio, ultimately improving strawberry agronomic traits.</div

Fig 3 -

(a) Nitrogen content in the rhizosphere soil after fertilizer treatment. AN, total nitrogen; TN, available nitrogen. (b) Phosphorus content in the rhizosphere soil after fertilizer treatment. AP, total phosphorus; TP, available phosphorus. (c) Potassium content in the rhizosphere soil after fertilizer treatment. AK, total potassium; TK, available potassium. (d) Correlation matrix for strawberry phenotypes and soil composition characteristics. Blue and red dots represent negative and positive correlations, respectively. *p p p < 0.001.</p

Fig 4 -

(a, b) Chao1 index showing bacterial (a) and fungal (b) community structure in the rhizosphere soil of strawberry plants treated with different levels of fertilizer. The horizontal bars within boxes represent medians. (c) Principal coordinate analysis (PCoA) based on the weighted Bray-Curtis distance of the bacterial communities. Permutational multivariate analysis of variance (PERMANOVA) was used to detect statistically significant differences between groups. (d) Heatmap based on the weighted Bray-Curtis distance of the fungal communities. (e) Significant differences in bacterial taxa between the fertilizer treatment groups as identified with linear discriminant analysis (LDA) coupled with effect size (LEfSe) analysis (LDA > 4 and p (f) Significant differences in fungal taxa between the fertilizer treatment groups as identified with LEfse analysis (LDA > 4 and p < 0.05).</p

Fig 2 -

(a) Urease, sucrase, and catalase activity in strawberry rhizosphere soil. (b) Range analysis and level difference analysis of urea, sucrose, and catalase activities in strawberry rhizosphere soil with combined nitrogen, phosphorus and potassium fertilizer application within each column, k1, k2, and k3 represent levels one (low), two (medium), and three (high) for each factor. r represents the range of factors between levels.</p

Effects of different nitrogen, phosphorus, and potassium fertilization treatments on strawberry phenotypes from 30–120 d after planting.

Effects of different nitrogen, phosphorus, and potassium fertilization treatments on strawberry phenotypes from 30–120 d after planting.</p

S1 Fig -

S1-S2: (1) Microbial composition is presented at phylum and genus levels; (S2): Significant difference analysis was conducted on the bacterial. (PDF)</p

L9 orthogonal test design.

Nitrogen (N), phosphorus (P), and potassium (K) exert various effects on strawberry (Fragaria ananassa Duchesne) yields. In this study, we employed an orthogonal experimental design (T1-T9) with three fertilization treatments (N, P, and K) at three levels to identify an optimal fertilization scheme for strawberry cultivation. The effects of fertilizer combinations the rhizosphere soil microbial community were also explored by using bacterial full-length 16S rRNA and fungal ITS (internal transcribed spacer) sequencing (30 samples for each analysis). The results showed that the average plant height and leaf area of the fertilized groups were 24.6% and 41.6% higher than those of the non-fertilized group (T0). After 60 d of planting, the sucrase activity in the T6 group increased by 76.67% compared to the T0 group, with phosphate fertilizer exerting a more significant impact on sucrase activity. The T6 treatment group had the highest alpha diversity index among bacterial and fungal microorganisms, and had a different microbial community structure compared with the control group. The most abundant bacterial taxa in the strawberry rhizosphere soil were Proteobacteria, Bacteroidota, and Acidobacteriota, and the most abundant fungal phyla were Monoblepharomycota, Glomeromycota, and Mucoromycota. Application of the optimal combined fertilizer treatment (T6) significantly increased the abundance of Proteobacteria and altered the abundance of Gemmatimonas compared to other treatment groups. Notably, Gemmatimonas abundance positively correlated with strawberry plant height and soil N, P, and K levels. These findings indicated that the relative abundance of beneficial bacteria could be enhanced by the application of an optimal fertilizer ratio, ultimately improving strawberry agronomic traits.</div

Fungus sample information.

Nitrogen (N), phosphorus (P), and potassium (K) exert various effects on strawberry (Fragaria ananassa Duchesne) yields. In this study, we employed an orthogonal experimental design (T1-T9) with three fertilization treatments (N, P, and K) at three levels to identify an optimal fertilization scheme for strawberry cultivation. The effects of fertilizer combinations the rhizosphere soil microbial community were also explored by using bacterial full-length 16S rRNA and fungal ITS (internal transcribed spacer) sequencing (30 samples for each analysis). The results showed that the average plant height and leaf area of the fertilized groups were 24.6% and 41.6% higher than those of the non-fertilized group (T0). After 60 d of planting, the sucrase activity in the T6 group increased by 76.67% compared to the T0 group, with phosphate fertilizer exerting a more significant impact on sucrase activity. The T6 treatment group had the highest alpha diversity index among bacterial and fungal microorganisms, and had a different microbial community structure compared with the control group. The most abundant bacterial taxa in the strawberry rhizosphere soil were Proteobacteria, Bacteroidota, and Acidobacteriota, and the most abundant fungal phyla were Monoblepharomycota, Glomeromycota, and Mucoromycota. Application of the optimal combined fertilizer treatment (T6) significantly increased the abundance of Proteobacteria and altered the abundance of Gemmatimonas compared to other treatment groups. Notably, Gemmatimonas abundance positively correlated with strawberry plant height and soil N, P, and K levels. These findings indicated that the relative abundance of beneficial bacteria could be enhanced by the application of an optimal fertilizer ratio, ultimately improving strawberry agronomic traits.</div

Fig 5 -

(a, b) Redundancy analysis of the impacts of soil composition on rhizosphere bacterial (a) and fungal (b) community structure. The arrow length represents the intensity of the indicated environmental factor’s influence on community changes (i.e., a long arrow represents a strong impact of the indicated environmental factor). The angle between the arrow and the axis represents the correlation between the indicated environmental factor and the axis; smaller angles correspond to higher correlations. The distance between each sample point and arrow indicates the strength of the effect of that environmental factor on the sample. The location of a sample in the same direction as an arrow indicates a positive correlation between the environmental factor and changes in the microbial community; the location of a sample in the opposite direction compared to an arrow indicates a negative correlation. (c, d) Correlation network analyses of soil microorganisms and soil physicochemical properties. Network analyses are shown for soil bacterial (c) and fungal (d) taxa and soil constituents. Circular nodes represent species (outer ring); square nodes represent environmental factors (inner ring). Circular node colors represent taxa at the genus level. Pink and light green lines indicate positive and negative correlations, respectively. (e, f) Spearman’s correlation coefficient values show the relationship between the presence of a fungal (e) or bacterial (f) taxon and the 17 phenotypic indices measured. Red and blue indicate positive and negative associations, respectively, between each measurement and the indicated species. *p p p < 0.001.</p