The role of reactive oxygen species in pollen germination in Picea pungens (blue spruce).

Endogenous ROS, including those produced by NADPH oxidase, are required for spruce pollen germination and regulate membrane potential in pollen tubes; [Formula: see text] and H O are unevenly distributed along the tube. Recently, the key role of reactive oxygen species (ROS) in plant reproduction has been decisively demonstrated for angiosperms. This paper is dedicated to the involvement of ROS in pollen germination of gymnosperms, which remained largely unknown.