Fig. 3

Increased heat tolerance of the osmdhar4 mutant at seedling stage. a Schematic diagram of the OsMDHAR4 gene. In the genomic DNA, exons, introns, and untranslated regions are indicated by black boxes, lines between boxes, and white boxes, respectively. The T-DNA insertion site is located in the first intron, 254 bp downstream of the start codon ATG. LB, left border of the T-DNA; RB, right border of the T-DNA. Arrows F1, R1, and L4 represent the primers used in the genotyping of the osmdhar4 mutant. b Expression analysis of OsMDHAR4 in the osmdhar4 mutant detected by qRT-PCR. The rice Actin1 gene was used as the internal control. Error bars indicate the SE based on three technical replicates. c 5.5- to 6.5-leaf stage WT and the osmdhar4 mutant plants were growing in barrels filled with well-mixed soil. The left and right half of each barrel was planted with WT and mutant plants, respectively. Plants were treated with high temperature (45 °C) for 72 h, followed by culturing under normal conditions for 7 d. The photograph was taken before heat stress and after recovery. d Comparison of survival rates of WT and the osmdhar4 mutant after heat stress. Error bars indicated the SE based on three biological replicates. *, P < 0.05, by Student’s t-test. e Water loss from detached leaves of WT and the osmdhar4 mutant at indicated time points. FW, Fresh Weight