Fig. 2From: Combining GS-assisted GWAS and transcriptome analysis to mine candidate genes for nitrogen utilization efficiency in Populus cathayanaClustering of transcriptome samples and statistical results of differentially expressed genes (DEGs). a Principal component analysis (PCA) of 78 samples b Sample correlation coefficients, with redder colors indicating higher correlation coefficients c Hierarchical clustering analysis of DEGs. d The number of upregulated and downregulated DEGs in each comparison groupBack to article page