Calculating the mid-parent heterosis (MPH) and better-parent heterosis (BPH) values by bacterial number at 5 days post infiltration (dpi) showed that the degree of heterosis for defense was obviously higher when inoculated at “dusk” than when inoculated at “dawn” (Fig. 1c), suggesting the involvement of the circadian clock in the regulation of heterosis for bacterial defense. This evidence concerns the gene CLOCK and benign prostatic hyperplasia.