Figure 6.

High temperatures affect Pi nutrition.

(A) Venn diagrams of differentially expressed genes (DEGs) between different comparisons (up- or downregulated genes) in roots or shoots. Circled numbers indicate the number of genes specifically deregulated between 32TGRooz and 22SR but not under other conditions.

(B) Gene ontology (GO) heatmap of specific genes (circled in A) in roots (R) or shoots (S) that were up- or downregulated (red and blue rectangles, respectively).

(C) Venn diagrams of DEGs deregulated by Pi starvation and by the effect of temperature between 32TGRooZ and 22SR in both roots and shoots. Red and blue boxes correspond to up- and downregulated genes, respectively.

(D) Free Pi level in roots or shoot of SR22, SR32, or 32TGRooZ Arabidopsis seedlings grown in a medium containing Pi for4 days and then transferred to different temperatures for 6 additional days. Values correspond to nmoles Pi per plant.

(E and F) Root length (E) and emerged LRs (eLR) (F) in WT, phr1 phl1, or pho2 mutants grown for 4 days at 22°C and then transferred to 22SR, 32SR, or 32TGRooZ conditions for 6 additional days. Significance was analyzed by ANOVA and Tukey’s honestly significant difference (HSD) post-test. Different letters indicate significant differences.

(G) Shoot or root fresh weight of WT, phr1 phl1, or pho2 mutants grown for 4 days at 22°C and then transferred to 22SR, 32SR, or 32TGRooZ conditions for 6 additional days. Values are expressed relative to those at 22°C.

(H) Shoot Pi level (nmoles/plant) in WT, phr1 phl1, or pho2 mutants grown as in (G). Values are expressed relative to those at 22°C. Asterisks indicate significant differences with respect to 22°C by t-test. ∗∗p < 0.01; ∗∗∗p < 0.001.