FIGURE 6.
Effects of heat priming and post-anthesis heat stress on the chlorophyll (A,B) and soluble protein content (C,D) in flag leaves of Yangmai 18 and Yannong 19 at the grain-filling stage from 2016 to 2017. NN refers to no heat priming + no heat stress at the grain-filling stage (control); NH refers to no heat priming + heat stress at the grain-filling stage; PSH refers to heat priming at the stem-elongation stage + heat stress at the grain-filling stage; PBH refers to heat priming at booting + heat stress at the grain-filling stage; PAH refers to heat priming at anthesis + heat stress at the grain-filling stage. The data are means ± SE (n = 3). Lowercase letters refer to significant differences between the treatments (P < 0.05). Whiskers above the bars indicate the standard error.