Fig. 6. Overexpression of BrJMJ18^Par mediates plant growth under both greenhouse and field high temperature conditions.

a The aboveground biomass evaluation of the BrJMJ18 transgenic Par plants grown in the greenhouse under different temperature conditions. BrJMJ18 transgenic Par plants grown under NC conditions for 9 weeks, and under NC conditions for 4 weeks, following another 5 weeks under high temperature (HT) conditions, respectively, were used for yield test. Data are means ± SD, n = 15. Asterisks indicate significant differences between NC and HT, two-tailed Student’s t-test (*p < 0.05, **p < 0.01, ***p < 0.001). BrJMJ18^PC-OX, p = 0.0011; BrJMJ18^Par-OX, p = 8.51×10⁻⁵. b, c The aboveground biomass evaluation of the BrJMJ18 transgenic Par plants grown in tunnel greenhouse under field conditions. The day maximum and minimum temperatures in the tunnel greenhouse were 52 °C and 31 °C, respectively, while the night maximum and minimum temperatures were 33 °C and 24 °C, respectively. b Plants were harvested at 55 days after sowing. c Plants were harvested at their proper picking stages. Data are means ± SD, n = 15. Asterisks indicate significant differences between BrJMJ18^Par-OX and the other three plants, two-tailed Student’s t test (*p < 0.05). In (b), BrJMJ18^Par-OX and BrJMJ18^PC-OX, p = 0.029; BrJMJ18^Par-OX and BrJMJ18^Par-CR, p = 0.03. In (c), BrJMJ18^Par-OX and BrJMJ18^PC-OX, p = 4.87E×10⁻⁶; BrJMJ18^Par-OX and BrJMJ18^Par-CR, p = 2.5 × 10⁻⁶; BrJMJ18^Par-OX and Par, p = 7.56 × 10⁻⁵. d–g Photos of the BrJMJ18 transgenic Par plants grown in tunnel greenhouse under field conditions. d, Par controls; e, BrJMJ18^Par-OX plants; f, BrJMJ18^Par-CR plants; g, BrJMJ18^PC-OX plants. For box plots (a–c), the box encompasses two middle quartiles, with a central line showing the median. Whiskers extend to the furthest data point within 1.5 times the interquartile range. Source data are provided as a Source Data file.