ISSN 10227954, Russian Journal of Genetics, 2011, Vol. 47, No. 9, pp. 1084–1090. © Pleiades Publishing, Inc., 2011.
Soil seed banks include all live seed that is either
buried or on the soil surface and represents an impor
tant component in the development and maintenance
of plant communities . It may be regarded as a
potential plant population. The seed bank is signifi
cant to renewing degraded ecosystems and creating
future plant communities [2–4].
Considerable research has been conducted by ecol
ogists on the properties of seed banks since the 1970's.
Seed bank properties that have been examined include
their distribution pattern [5, 6], the dynamics of their
density in the soil , their accumulation as seed rain
and germination [8–11] and their role in the recon
struction and succession of woodland vegetation .
In a study to examine the number of viable seeds and
its vertical distribution in soil on the Typical Steppe,
Zhong et al. (1999), showed that the total number of
seeds in a unit area of the seed pool was lower than the
number in the seed rain . This occurred because
many seeds in the pool were not viable and had been
added through factors such as mowing before they had
matured. Tang and Cao (1999) researched the rela
tionship between soil seed bank and aboveground veg
etation in tropical forests and found that seed germi
nation in the soil seed bank was inhibited under the
The article is published in the original.
closed canopy . These seeds would germinate rap
idly, and played an important role in vegetation resto
ration when forest gaps or openings occurred as a
result of disturbance.
An important attribute of the soil seed bank is its
genetic memory developed with the addition of seeds
over several years and under potentially different selec
tive regimes. Therefore, the soil seed bank is a latent
plant population . It is not only a source of vegeta
tion replenishment and regeneration, but also a mecha
nism for preserving plant species diversity. The spatial
temporal pattern of the seed bank is important for
restoring the degraded ecosystem and defines the com
posite plant community. The seed bank thus has the
potential to dampen the response of a plant population
to selective pressures and to increase the rate of evolu
tion [15, 16]. Therefore, the soil seed bank can influ
ence the genetic variances of plant populations and thus
affect their functional performance in the plant com
munity . However, the potential contribution of the
seed bank to the latent population depends on those
seeds that can germinate and establish successfully,
which normally occurs, for
early spring (Zhao M, unpublished data).
is a perennial, xerophytic bunch grass
and an important forage species in the Typical Steppe
of Inner Mongolia. It can tolerate drought, grazing,
Genetic Comparisons between Seed Bank and
and M. Zhao
College of Life Sciences, Inner Mongolia Agricultural University, Hohhot 010018, Inner, Mongolia, China
Department of Grassland Science, College of Ecology and Environmental Science, Inner Mongolia Agricultural University,
Hohhot, Inner Mongolia, 010018, China
Received January 13, 2011
—The soil seed bank represents the potential plant population since it is the source for population
replacement. The genetic structure of a
(Roshev.) plant population and its soil seed bank was
investigated in the Xilinguole Steppe of Inner Mongolia using random amplified polymorphic DNA (RAPD)
analyses. The population was sampled at two sites that were in close proximity to each other (0.5 km apart).
Thirty plants and 18 seed bank samples were taken from each site to determine the genetic diversity between
sites and between sources (plant or seed). The material was analyzed using 13 primers to produce 92 loci.
Eightysix were multiloci, of which 23 loci (26.74%) of allele frequencies showed significant differences
0.05). The genetic similarity between two seed bank sites was 0.9843 while the genetic similarity between
two plant sites was 0.9619. Their similarities were all greater than that between the seed bank and plant pop
ulations. An analysis of their genetic structure showed that87.86% of total variation was derived by twoloci.
Genetic structures between plant and soil seed bank populations in
were different due to the vari
ance of mean gametic disequilibria and mean gene diversity. AMOVA results showed that the majority of vari
ance (88.62%) occurred within sites, 12.75% was from betweengroups. Further research is needed to inves
tigate the selective function in maintaining the genetic diversity of