Fig 1.
Schematic diagram of the experimental design.
Plants were treated at 35°C and 45°C and subjected to morphological, physiological, biochemical, and shotgun proteomic analysis.
Fig 2.
Effect of heat stress on morphological parameters of Htol and Hsus genotypes (A) plant height (cm); (B) nodes on the main stem; (C) inter-nodal length (cm); (D) HBFB (cm) (E) NBFB (F) BSFP (G) BSSP. Error bars indicate the mean ± standard deviation of three experimental mean values. P-values of tolerant control and tolerant stress and susceptible control and susceptible stress are given in the table of each section, and *p < 0.05; **p < 0.01; ***p < 0.001 according to ONE-WAY ANOVA. PH = plant height, NMS = nodes on the main stem, INL = inter-nodal length, HBFB = height bearing 1st effective boll, NBFB = node bearing 1st effective boll, BSFP = bolls set in the 1st position; BSSP = bolls set in the 2nd position.
Fig 3.
Pearson correlations between different morphological parameters in (A) Htol and (B) Hsus genotypes under heat stress. The red squares indicate a negative correlation, the blue squares a positive correlation, and the yellow squares a significant positive correlation.
Fig 4.
Gas exchange parameters in the leaves of Htol and Hsus genotypes in response to heat stress (A) Temperature leaf (°C) (B) Net photosynthetic rate (Pn) (C) Transpiration rate (E) (D) Stomatal conductance (C). Error bars indicate the mean ± standard deviation of three experimental mean values. P-values for tolerant control and tolerant stress and susceptible control and susceptible stress are given in the table of each section and *p < 0.05; **p < 0.01; ***p < 0.001 according to ONE-WAY ANOVA.
Fig 5.
Effect of heat stress on biochemical parameters of Htol and Hsus genotypes: (A) chlorophyll concentration (mg/gFW); (B) proline contents (μmoles/g). The box plot showed the upper and lower quartiles with median and whisker lines that extended from the box, showing variability out of the upper and lower quartiles. *p < 0.05; **p < 0.01; ***p < 0.001 according to ONE-WAY ANOVA.
Fig 6.
Venn diagram showing the unique and shared proteins of Htol and Hsus genotypes in response to heat stress (A) unique and shared proteins of Htol genotypes (B) unique and shared proteins of Hsus genotypes (C) comparison of proteins in both genotypes under heat stress.
Fig 7.
(A) Pearson correlation heatmap of three biological replicates of the Htol genotype (B) Pearson correlation heatmap of three biological replicates of Hsus genotypes. The correlation values between ±1 is considered to be a strong correlation.
Fig 8.
(A) PCA of 3 biological replicates of Htol genotypes at the control and heat stress (B) PCA of 3 biological replicates of Hsus genotypes at the control and heat stress.
Fig 9.
(A) Volcano plot of 3 biological replicates of Htol genotypes at control and heat stress (B) A volcano plot of three biological replicates of Hsus genotypes at the control and heat stress. Each point represents a protein with a difference between the abundance of each genotype at control and stress along the x-axis and the log10 p-value along the y-axis. The red and green points represent the upregulation and downregulation of proteins, respectively.
Fig 10.
Selected functional classes of the significantly differentially expressed proteins under heat stress.
The bars illustrate the percentage of each class concerning total differentially expressed proteins. The orange color showed the tolerant plant and the yellow susceptible genotypes, as indicated.
Table 1.
Selected significantly differentially expressed proteins between the tolerant and susceptible cotton genotypes.
Fig 11.
Various classes of transporter proteins were identified from the leaves of Htol and Hsus genotypes in response to heat stress following the Transporter Classification Database (TCDB).