The seed bank is thought to be important for the conservation and restoration of the
genetic diversity of the above ground plant population. It has been proposed that it may be
no use to compare the genetic diversity between seed bank and above ground plants if
there was no habitat fragmentation. Whether this prediction holds for aquatic plants is still
unknown. Here, ISSR analysis of a common wetland species Heleocharis valleculosa
(Cyperaceae) was conducted to evaluate if the seed bank has higher, equal or lower genetic
variation than the above ground vegetation. Our results showed high genetic diversity in
the seed bank, so the seedbank can act as a storehouse of genetic variation for the above
ground vegetation, especially in unfavorable conditions. Thus, unlike terrestrial habitats
where genetic diversity is often low, wetlands that are connected with water flow can
accumulate many genotypes in the seed bank and the question of how genetic diversity
varies above and below ground is still open.