During embryonic development in humans and other mammals, sperm and egg cells are essentially wiped clean of chemical modifications to DNA called epigenetic marks. They are then held in reserve to await fertilization.
In flowering plants the scenario is dramatically different. Germ cells don’t even appear until the post-embryonic period – sometimes not until many years later. When they do appear, only some epigenetic marks are wiped away; some remain, carried over from prior generations – although until now little was known about how or to what extent.
View the original article here: Scientists uncover mechanism by which plants inherit epigenetic modifications