TRNT1 and infection: Considering that both FCS and FCA showed significantly growth heterosis and the same below-low parent expression patterns of CCA1 at ZT6 no matter inoculated with Pst DC3000 or not (Fig. 1a, d, e and Supplementary Fig. 2) and that plants accumulate energy and materials required for growth during the day because the light-requiring step in chlorophyll biosynthesis can be activated45, we speculated that CCA1 may enhance heterosis for growth in hybrids in middle of the infection day (6 hpi).