“…In the Arabidopsis mutant feronia ( fer ), the pollen tube fails to arrest and thus continues to grow inside the female gametophyte without rupture for the release of sperms [ 17 , 18 ]. Besides the role in reproduction, accumulating evidence suggests that FER plays critical roles in a diversity of biological processes, such as root growth [ 135 , 136 , 137 ], immune responses [ 21 , 138 , 139 , 140 , 141 , 142 ], environmental adaptations [ 143 , 144 , 145 , 146 ], etc.…”