College;
of;
Resources;
and;
Environment,;
South;
China;
Agricultural;
University,;
Guangzhou;
510642,;
China;
Institute;
of;
Cellular;
and;
Molecular;
Botany,;
Bonn;
University,;
Bonn;
D-53115,;
Germany;
Electrophysiology;
Laboratory,;
Department;
of;
Horticulture,;
University;
of;
Florence,;
Viale;
delle;
Idee;
30,;
1-50019;
Florence,;
Italy;