Figure 5.

Evaluation of abiotic stress tolerance of NAC transcription factor mutant lines.

(A) The number of identified TFs and the responsiveness of each TF family to abiotic stress. Only TF families with more than 100 genes are shown. The size of the circle indicates the number of genes that were differentially expressed in roots or leaves of KN9204 under drought/salt stress, with a higher percentage indicated by a darker color.

(B) Summary of the KN9204 EMS mutant lines that contained NAC TF mutations.

(C) The maximum root length (MRL) distribution of 100 mutant lines under different conditions.

(D) The mutant lines exhibited differences in drought and salt stress sensitivity. Each mutant line is plotted as a point, and their MRLs under different conditions are linked with a dashed line.

(E) The ranking of 100 mutant lines using MRL_Salt/CK, SL_Salt/CK, MRL_Drought/CK, and SL_Drought/CK. In each box, mutants in the upper quarter, middle half, and lower quarter were defined as tolerant, less sensitive, and sensitive, respectively. Tukey’s multiple comparisons test was used to determine the significance of differences between MRL_Salt/CK, SL_Salt/CK, MRL_Drought/CK, and SL_Drought/CK. Different letters indicate significant differences at P < 0.05.

(F) Overview of mutant lines with different responses to drought and salt stress.

(G) The number of NAC TFs that responded to different stresses in each DEG group. TFs for which at least one mutant line exhibited a sensitive or tolerant phenotype under drought and salt stress were counted. TFs that were differentially expressed under drought stress, salt stress, or both conditions were assigned to the drought DEGs, the salt DEGs, and the drought and salt DEGs, respectively.