Fig. 4

Comparison of endophytic metabolites in the stems of the HR and HS sugarcane cultivars. a Venn plot; b OPLS-DA scores plot; c HR vs HS comparison cultivar response permutation test of the OPLS-DA model; d Volcano map. The X-coordinate is the multiple change value of the difference in metabolite expression between the two groups, named log₂FC; the Y-coordinate is the statistical test value of the difference in metabolite expression, named − log₁₀(P-value); the higher the value, the more significant the difference in expression. Each dot represents a specific metabolite, and the size of the dot represents the Vip value. The left and right points indicate the metabolites with down- and upregulated expressions, respectively. e Clustering heat map