全 文 ：Advances in Understanding Seed Dormancy at the Whole-seed Level:
An Ecological , Biogeographical and Phylogenetic Perspective
?
BASKIN Carol C
1 , 2
, BASKIN JerryM
1
( 1 Department of Biology, University of Kentucky, Lexington , KY 40506 , USA ;
2 Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY 40546 , USA )
Abstract: Following a brief account of theearly foundations of seedgermination ecology sensu lato, somehistorical andre-
cent developments pertaining to the ecology, biogeography and phylogeny of seed dormancy are discussed .
Key words: Biogeography of seed dormancy; Ecology of seed dormancy; Phylogeny of seed dormancy; Seed dormancy;
Seed germination
CLC number : Q 948 Document Code : A Article ID: 0253 - 2700 (2008) 03 - 279 - 16
A celebration publication (festschrift) is an oppor-
tunity to (1) think about the early work that helped to
establish a particular discipline, (2) reflect on its cur-
rent focal pointsof research activity and (3) contemplate
what thefuturedirectionsmight beas thefield continues
to develop . Here, we wish to celebrate the ecology of
seed dormancy and germination in its broadest sense
( sensu lato) .
Foundations
Control of seed germination in nature
The date when people first began to make obser-
vations on seed germination phenology and to wonder
why species might have different germination seasons
has not been recorded . However, the Greek philoso-
pher Theophrastus ( ca . 372 - 287 B . C .) had a keen
interest in seeds and commentedon the fact that germi-
nation was influenced by climatic factors ( Evenari ,
1980 - 81 ) . Indeed, one of the major focal points of
early research on germination ecology was trying to ex-
plainwhat controlled the timing of seed germination in
the field, i . e ., under natural habitat conditions . The
work of Went ( 1949 ) in the deserts of southwestern
USA and that of Koller ( 1955) , Evenari ( 1980 - 81)
and Gutterman ( 1981 ) in the deserts of Israel did
much to excite ecologists about trying to understand the
complexities of seedgermination in thenatural environ-
ment . This excitement was further enhanced when ecol-
ogists began to pay attention to datafromstudies onwa-
ter-permeable seeds with physiological dormancy in the
temperate climate of the United Kingdom ( Ratcliffe,
1961; Newman, 1963 ) and those on water-imperme-
able ( physically-dormant) seeds done in thearid region
of Australia byQuinlivan (1961) , all of which showed
that timingof dormancy-break played an important role
in timingof germination in the field .
With recognition that dormancy-break was corre-
lated with certain seasons of the year, e. g ., cold,
wet conditions of winter (cold stratification) , seed ger-
mination ecologists paid increased attention to the work
of seed physiologists who had been investigating the
specific dormancy-breaking requirementsof seeds in the
laboratory?greenhouse for several decades . For exam-
ple , Barton ( 1930 ) was studying the effects of cold
stratification on dormancy break in the early 1930s .
The subsequent“marriage”of ecology and physiology
in studies of seed dormancy break and germination
turned out to be avery productive approach .
One aspect of the control of timingof seed germi-
nation in the field that received considerable early at-
tention was germination of seeds in the soil , especially
weed seeds . It had long been recognized that arable
云 南 植 物 研 究 2008 , 30 (3) : 279～294
Acta Botanica Yunnanica DOI : 10 .3724?SP. J . 1143 .2008.08017
? ?Dedicated to the 30th Anniversary of Acta Botanica Yunnanica
Received date: 2008 - 02 - 15 , Accepted date: 2008 - 02 - 22
soils may contain large numbers of seeds ( Darwin,
1859 [ 1892 ] ) . Further, studies by Brenchley and
Warington ( 1936 ) showed that buried seeds of many
weeds werenot in a constant stateof readiness to germ-
inate . Thus, if seed-containing soil was disturbed in
one season ( e. g ., spring and?or autumn) seeds of a
particular species might germinate; however, if it was
disturbed in another season noseedlings of that species
appeared but thoseof another one might . The first di-
rect evidence that buried seeds of some species undergo
seasonal changes in their dormancy state was obtained
by Courtney ( 1968 ) for seeds of Polygonumaviculare,
and it was confirmed by Schafer and Chilcote ( 1970)
and Taylorson (1970) shortly thereafter . Concern about
buried seeds, especially from a weed-control perspec-
tive, resulted in studies on longevity of seeds in soil
(Telewski and Zeevaart, 2002 ) , development of sim-
ple models of the fate?dynamics of seeds in the soil
(Schafer and Chilcote, 1969 , 1970; Roberts, 1972)
and descriptions of two typesof transient and two types
of persistent seed banks (Thompson and Grime, 1979;
Grime 1981 ) ; the list of persistent seed bank types
subsequently was expanded to seven ( Roberts, 1981;
Baskin and Baskin, 1998) .
Oneof the products of early studies on control of
timing of germination in the field was the development
of theoretical models, in particular those of Cohen
(1968) . He worked in the randomly varying ( unpre-
dictable rainfall ) environment of the Negev Desert in
Israel . His models identified various ecological situ-
ations that may have lead to the selection of seed
dormancy, and they have served as the foundation for
much additional theoretical thinking about seeds (Ven-
able and Lawlor, 1980; Bulmer, 1984; Philippi and
Seger, 1989; Brown and Venable, 1991) .
Development of a dormancy classification system
Dormancy in seeds is recognized as the failure of
seeds to germinate, being particularly troublesome to
peoplewho may sowseeds that subsequently fail to ger-
minate . On the other hand, nondormant seeds are
those that germinate readily when placed under suitable
temperature, light, moisture andoxygen conditions . As
mentioned above, plant physiologists, e. g ., those at
the Boyce Thompson Institute in Yonkers [ now at
Ithaca] , NewYork (USA) , investigated thedormancy-
breaking requirements of seeds of many economically-
important species in the 1920s and 1930s ( Crocker and
Barton, 1957 ) . Much research was done in various
laboratories to determine ( 1 ) the best techniques for
making seed coats permeable in species with physical
dormancy, (2) theminimumlength of the cold stratifi-
cation period require to break dormancy and ( 3 ) the
optimal period of dry storage at roomtemperatures ( af-
terripening) required to break dormancy ( see Crocker
and Barton, 1957) . Crocker ( 1916 ) developed oneof
the first dormancy classification systems, in which he
distinguished seven kinds of dormancy with regard to
their cause: (1 ) underdevelopment of the embryo, (2)
water-impermeable seed or fruit coat, ( 3 ) mechanical
resistanceof seed covering layers, (4 ) low gas perme-
ability of seed covers, ( 5 ) metabolic ( physiological )
block in the embryo, (6) combined dormancy and (7)
secondary dormancy .
When Nikolaeva began her Ph . D . dissertation
researchon the“physiology of deep dormancy in seeds”
( translated into English in 1969 ) at the Komarov Bo-
tanical Institute in St . Petersburg, Russia, she knew
about Crocker′s classificationsystemand thework done
on seeds in various laboratories around the world ( see
references cited in Nikolaeva, 1969 ) . Using her
knowledge of theliterature andher vast experiencewith
seed dormancy, Nikolaevadevised themost logical and
detailed seed dormancy classification systemyet devel-
oped (Nikolaeva, 1969) , which she subsequently re-
vised slightly (Nikolaeva, 1977 , 2001 ) . Her systemis
based on seed internal structure ( e. g ., fully-devel-
oped vs . underdeveloped embryo) , role of seed cover-
ing layers ( i . e ., impermeability to water, mechanical
restriction to radicle emergence, presence of chemical
inhibitors) ; physiological requirements for dormancy-
break ( cold stratification and?or warm stratification) ;
and effectsof plant growth regulators on breaking phys-
iological dormancy .
In her systemof dormancy classification, Nikolae-
va gave both aname and a letter?number formula to the
seven types and various subtypes of dormancy she rec-
082 云 南 植 物 研 究 30 卷
ognized: three types of exogenous ( physical , chemical
and mechanical ) , three types of endogenous ( physio-
logical , morphological and morphophysiological ) and
many types of combinational ( exogenous plus endoge-
nous) dormancy . For example, deep simple epicotyl
dormancywas representedby the formulaB-C3
e
, where
B refers anunderdeveloped embryo, C3 to deep physio-
logical dormancy and superscript e to epicotyl ( Niko-
laeva, 1977 ) . After surveying available evidence,
Baskin and Baskin ( 1998 ) proposed that chemical and
mechanical dormancy be recognized only as a part of
physiological dormancy, and Nikolaeva (2004) agreed
with this conclusion .Later, Baskin andBaskin (2004)
published amodified version of Nikolaeva′s systemthat
included three hierarchical layers of classification:
class, level and type . In the modified version, Niko-
laeva′s physical , physiological , morphological , mor-
phophysiological and one type of combinational ( physi-
cal plus physiological ) dormancy are“ classes of
dormancy”(Baskin and Baskin, 2004) .
Variation in dormancy and germination
Within-in species variation in seed dormancy and
germination characteristics has great economic as well
as ecological importance . Thus, it isnot surprisingthat
inheritance of seed dormancy has been under almost
continuous investigation since the early 1900s, e. g .,
studies on peanut by Stokes and Hull ( 1930 ) . Fur-
ther, various aspects of seed dormancy and germina-
tion, including degree of dormancy ( Adkins et al. ,
1986) , rate of dormancy loss ( Jana et al. , 1979) and
germination requirements ( Whittington et al. , 1970 ) ,
are at least partly controlled by genetics . Seed poly-
morphism has a genetic component ( Antonovics and
Schmitt, 1986) , and the consequences of seed size on
germination (Harper and Obeid, 1967 ) and on subse-
quent sizeof seedlings (Wulff and Bazzaz, 1992) have
been studied in a number of species .
Another sourceof variation in seed dormancy and
germination characteristics is the environment experi-
enced by the mother plant while seeds are maturing .
This type of variation is called preconditioning or ma-
ternal effects, and some of the many factors causing it
include age of plant (Olson, 1932) , day length (Gut-
terman and Porath, 1975) , light quality ( McCullough
and Shropshire, 1970 ) , mineral nutrition ( Thurston,
1951) , position on mother plant (Negbi and Tamari ,
1963) , soil moisture ( Pallas et al. , 1977 ) and tem-
perature ( Junttila ( 1971 ) . Plants of the same species
growing in sites varying with respect to elevation (Mey-
er, 1990) , latitude (Wilcox, 1968) , salinity (Sands,
1981) and soil moisture (Youngberg, 1952 ) also vary
in seed dormancy and germination characteristics . One
of the challenges has been to decide if the observed
variation is due to genetics and?or preconditioning .
Thus, a number of common garden studies have been
done, and genetic (Hacker and Ratcliffe, 1989) , pre-
conditioning?environmental ( Nelson et al. , 1970 ) and
genetic x environmental (Quinn and Colosi , 1977) ef-
fects have been found .
Phylogenetic relationships
Martin′s ( 1946 ) family tree of seed phylogeny
and the accompanying body of work on embryo mor-
phology of 1287 generaof plantswas an important start-
ing point for considerations of the phylogenetic relation-
ships of seed dormancy . He placed seeds with small ,
underdeveloped embryos ( i . e ., they must grow inside
the seed before germination can occur) at the base of
the tree . Subsequent work in Russia by Grushvitzky
(1967 ) , analysesof taxonomic position [using Takhta-
jan′s ( 1986 , 1987) plant taxonomic classification sys-
tem] and seed characters by Nikolaeva ( 1999) and an
evaluation of evolution of embryo size in seed plants by
Forbis et al. (2002) supported the idea that underde-
veloped embryos areprimitive . However, it is well rec-
ognized that underdeveloped embryos also are present in
seeds of some advancedgroups of plants (Grushvitzky,
1967; Nikolaeva, 1999 ) . The first attempt to map
kinds of dormancy onto phylogenetic charts was by
Baskin and Baskin ( 1998 ) , who placed classes of
dormancyonto Takhtajan′s (1980) diagramfor showing
the evolutionary relationships within the angiosperms .
Recent ( 1980 - 2008) and on-going research
Research on the ecology of seed dormancy and
germination in the last part of the 20th century and be-
ginning of the 21st century has added significantly to the
1823 期 BASKIN and BASKIN: Advances in Understanding Seed Dormancy at theWhole-seedLevel : An . . .
strong early foundation of knowledge . In some cases,
work on previously-studied topics such as classes of
dormancy and soil seed banks has continued, but some
new fields of investigation such as the world biogeogra-
phy of seed dormancy and evolution of seed dormancy
in closely-related taxa has emerged . We will briefly
survey achievements in thesevarious research areas .
Classes of seed dormancy
Physiological dormancy ( PD) . For seeds with
nondeep PD, it has been known for many years that,
depending on the species, cold stratification ( Carpita
et al. , 1983) , GA3 ( Baskin and Baskin 1971 ) , in-
cubation temperatures (J unttila, 1973) , light (Scheibe
and Lang, 1965 ) or darkness ( Chen, 1968 ) may in-
crease growth potential of the embryo enough for the
radicle to emerge through the seed coat, and any other
covering layer ( s) that might be present, and thus
germinate . However, for endospermous seeds it has
been found that the endosperm becomes less restrictive
for growth, just prior to emergence of the radicle .
Breakdown of the endosperm cap over the tip of the
radicle is correlated with production of GA (Groot and
Karssen, 1987) and with activities of various enzymes
( e. g ., Toorop et al. , 2000) and expansins (Chen et
al. , 2001) . This is an on-going area of research, and
thegenes responsible for the various aspects of endo-
sperm cap weakening are being determined (Mella et
al. , 2004) .
In temperate regions, seeds with deep PD require
several weeks to a few months of cold stratification to
becomenondormant (ND) , at which timeseeds usually
germinate best at low temperatures; sometimes germi-
nating at the cold-stratifying temperature ( Baskin and
Baskin, 1998) . Deep PD that is broken only by sever-
al months of warm ( 25?15℃ ) stratification has been
found in seeds ( actually drupelets) of Leptecophylla
tameiameiae ( Ericaceae) from the tropical montane
zone of Hawaii ( Baskin et al. , 2005 ) . After dormancy
break, 25?15℃ was the optimum temperature regime
for germination . Future research may prove that mem-
bers of the Burseraceae, Clusiaceae, Combretaceae,
Euphorbiaceae, Fagaceae, Flacourtiaceae, Hernandi-
aceae, Lecythidaceae, Meliaceae, Menispermaceae,
Myrtaceae, Rhizophoraceae, Rubiaceae, Rutaceae,
Symplocaceae and Verbenaceae that did not germinate
until after 90 days in Ng′s ( 1991 , 1992 ) germination
phenology studies of Malaysian forest trees also have
deep PD .
Physical dormancy ( PY ) . Since 1980 , several
significant advances have been made with regard to
seeds with PY . First, the list of families with one or
more specieswithwater-impermeable seedor fruit coats
has been refined and now includes Anacardiaceae,
Bixaceae, Cannaceae, Cistaceae, Cochlospermaceae,
Convolvulaceae ( including Cuscutaceae) , Curcurbita-
ceae ( Sicyos) , Dipterocarpaceae ( subfamilies Mon-
toideae and Pakaraimoideae, but not Diptero-
carpoideae) , Fabaceae ( subfamilies Caesalpinioideae,
Mimosoideae and Papilionoideae) , Geraniaceae, Mal-
vaceae ( including Bombacacaceae, Sterculiaceae, and
Tiliaceae, sensu APG, 2003) , Nelumbonaceae, Rham-
naceae, Sapindaceae, Sarcolaenaceae ( Baskin et al. ,
2000) and Surianaceae ( Baskin et al. , 2006 ) . Also,
the specialized structure for entry of water (water gap)
has been identified in five additional families: Anacar-
diaceae, carpellary micropyle (Li et al. , 1999 ) ; Can-
naceae, imbibition lid (Grootjen andBouman, 1988) ;
Cistaceae, bixoid chalazal plug ( Thanos and
Georghiou, 1988; Nandi , 1998 ) ; Convolvulaceae,
bulges near hilum in most genera ( Jayasuriya et al. ,
2007) but hilum in Cuscuta ( Jayasuriya et al. , un-
publ .) and Dipterocarpaceae, bixoid chalazal plug
(Nandi , 1998 ) . Although fungi and?or soil abrasion
have received some attention as the agents that made
seeds water permeable; still , little, or no, experimen-
tal evidence has been produced to support these ideas
( Baskin and Baskin, 2000) . However, there is an in-
creasing body of data indicating that the water gap
opens in response to changes in environmental condi-
tions, in particular temperature ( see below) ; thus,
these structures serve as environmental sensors .
One of the most exciting discoveries about seeds
with PY is that, at least in some species, dormancy-
break innature involves twosteps: ( 1) seeds aremade
sensitive but remain impermeable, and ( 2 ) sensitive
seeds respond to certain environmental conditions and
282 云 南 植 物 研 究 30 卷
thus become water-permeable and germinate . Depend-
ing on the species, seeds may become sensitive if
stored moist (or at high RH) at high, e. g ., Trifoli-
um subterraneum ( Taylor, 1981 , 2005 ) , Ornithopus
compressus (Taylor and Revell , 1999 ) and Ipomoea la-
cunosa ( Jayasuriya et al. , 2008 ) , or at low, e. g .,
Melilotus albus, Medicago lupulina, Lotus cornicula-
tus and Trifoliumrepens (Van Assche et al. , 2003 ) ,
temperatures . Although seeds are exposed to the first
step and become sensitive to dormancy break, they do
not germinate unless step 2 occurs . In fact, seeds of
I . lacunosa can cycle between sensitive and insensitive
states . Thus, if sensitiveseeds of I . lacunosa aredried
at high temperatures ( instead of being on moist sand)
they become insensitive and will not respond to the
treatment ( 35℃ on wet sand for ≥ 2 h) that breaks
dormancy, i . e ., causeswater gap to open (Jayasuriya
et al. , 2008 ) . Seeds made insensitive can again be
made sensitive .
Morphophysiological dormancy ( MPD ) . To
break MPD, seeds must be exposed to appropriate en-
vironmental conditions to break PD and to promote
growth of the embryo ( break MD) . Seven levels of
MPD were distinguished by Nikolaeva ( 1977 ) , and
they can be divided into two general categories: sim-
ple, embryo grows at relatively high ( > 10℃ , i . e .
temperatures too high for cold stratification) ; and com-
plex, embryo grows during cold stratification . Nondeep
simpleMPD was not mentioned by Nikolaeva ( 1977 ) ,
and it was first described in seeds of thewinter annual
Chaerophyllum tainturieri ( Baskin and Baskin,
1990) . Thus, eight levels of MPD now are known . In
seeds of C. tainturieri , PD is broken during summer,
and embryo growth occurs in autumn if seeds are ex-
posed to light . In some seeds with nondeep simple
MPD, however, PD is broken during cold stratifica-
tion, and embryogrowth andgermination occur in spri-
ng (Walck et al. , 1999) .
Another interesting discovery related to MPD is
that some of Martin′s ( 1946)“dwarf seeds”, e. g .,
Campanulaceae andGentianaceae (Baskin and Baskin,
2005) , have small underdeveloped embryos . Underde-
veloped embryos also occurred in seeds of six endemic
Hawaiian lobelioid shrubs ( Baskin et al. , 2005 ) .
However, although seeds of Drosera anglica, which
Martin considered to be dwarf, have small embryos in
relation to size of endosperm, embryos did not grow
prior to radicle emergence ( Baskin and Baskin,
2005) .
With regard to Martin′s ( 1946) classification sys-
temof seeds, there are 10 types based on embryo and
endosperm characteristics and two additional types
basedon seed size: dwarf , 0 . 3 - 2 .0 mm and micro,
≤0 .2 mm . However, his“dwarf seed families”could
not be distinguished from his other small-seeded non-
dwarf families on the basis of endosperm texture, seed
coat anatomy, embryo morphology, class of dormancy
or phylogenetic position . Consequently, Martin′s key
has been revised to place all seeds into categoriesbased
on embryo and endosperm characteristics ( Baskin and
Baskin, 2007) .
Seed banks
Worldwide, theone topic related to the ecology of
seed dormancy and germination that has received the
most attention from 1980 to present is seed banks .
Much of the work is related to soil seed banks, but
considerable effort has been devoted to aerial seed
banks, especially serotiny ( Cowling et al. , 1987;
Lamont et al. , 1991 ) . The suggested minimum period
of time for seeds to live in soil and be called a persis-
tent seed bank has been expanded from ≥ 1 year
(Thompson and Grime, 1979) to the second germina-
tion season ( Walck et al. , 2005 ) to accommodate
seeds that are in the dormant phase of the annual
dormancy?nondormancy cycle at the end of 1 year and
those that requiremore than 1 year to become nondor-
mant . It has been made emphatically clear that seeds
do not have to be dormant to remain ungerminated and
viable in thesoil for longperiodsof time (Thompson et
al. , 2003; Fenner and Thompson, 2005) .
Studies to determine the species represented in
persistent seedbanks andnumber of seedsof thesespe-
cies have been ( and continue to be) done in various
habitats around the globe . Many aspects of soil seed
banks are being studied, and all we can do in a brief
review is to list someof them: (1) shapes and sizesof
3823 期 BASKIN and BASKIN: Advances in Understanding Seed Dormancy at theWhole-seedLevel : An . . .
seeds with a high probably of forming a persistent seed
bank ( Thompson et al. , 1993; Funes et al. , 1999 ) ;
(2) reasons for spatial heterogeneity ( Fernandez et
al. , 2002 ) ; (3) causes of seed death includingpreda-
tion ( Honek et al. , 2003 ) , solarization ( Mas and
Verdu, 2002 ) and flooding ( Voesenek and Blom,
1992) ; ( 4 ) comparison of seed rain and seed bank
(Pakeman and Small , 2005) ; ( 5) dynamics of buried
seeds of individual species ( Wilson and Witkowski ,
2003; Shimono and Washitani , 2004 ) ; (6 ) longevity
of seeds in soil ( Bekker et al. , 1998; Arroyo et al. ,
2004) ; (7 ) maximum number of seeds in arable soils
(D′Angela et al. , 1988 ) ; ( 8 ) maximum depth of
seedling emergence ( Benvenuti et al. , 2001; Grundy
et al. , 2003) ; (9 ) weed seed emergencemodels ( Col-
bach et al. , 2005; Wang et al. , 2006 ) ; ( 10 ) seed
bank management to facilitate restoration of plant com-
munities ( Hoelzel and Otte, 2003; Mengistu et al. ,
2005) ; and ( 11 ) potential of seed bank for restora-
tion, including good species representation ( Kalamees
and Zobel , 2002; Sakai et al. , 2005 ) , some species
not in seed bank ( Senbeta and Teketay , 2002; Ro-
drigues and Matos, 2006 ) , weed seeds present ( Bid-
well et al. , 2006; Roovers et al. , 2006 ) , seeds of
aliens present (Shen et al. , 2004; Yakimowski et al. ,
2005) and seeds of rare species present ( Auld and
Scott, 2004 ) .
Dormancy cycling
Annual dormancy?nondormancy or conditional
dormancy?nondormancy cycles have been documented
in buried seeds of various winter annuals, summer an-
nuals and perennials exposed to the temperate-zone an-
nual temperature cycle ( Khan and Karssen, 1980;
Baskin and Baskin 1998) . However, some seeds come
out of dormancy and remain nondormant during burial
for many years ( Baskin and Baskin, 1985a) . Under-
standing why buried seeds can undergo changes in their
dormancy statehas been enhanced by experimental data
showing that lowwinter temperatures break PD in seeds
of many summer annuals and can induce nondormant
seeds of winter annuals into dormancy . On the other
hand, high summer temperatures can induce nondor-
mant seeds of summer annuals into dormancy and can
break dormancy in seeds of winter annuals (Baskin and
Baskin, 1998) . Further, asmany seedswith PD come
out of dormancy the range of temperatures over which
they germinate increases, and as they enter dormancy
the rangeof temperaturesover which theygerminatede-
creases; this is called thedormancy continuum ( Baskin
and Baskin, 1985b) . Models of the seasonal dynamics
of buriedseeds includeseasonal changes in temperature
rangefor germination (Vleeshouwers andBouwmeester,
2001) , as well as changes in sensitivity to light (Batlla
and Benech-Arnold, 2005 ) and hydrothermal time
(Ekeleme et al. , 2005) . Seeds also change in sensi-
tivity to other factors, e. g ., plant growth regulators
and substrate moisture during the dormancy cycle
( Baskin and Baskin, 1998) .
Germination requirements of nondormant seeds
After seeds, especially those with PD, become
nondormant various environmental factors may play a
role in determining if they germinate (Vleeshouwers et
al. , 1995 ) . It has long been known that seeds may
require light for germination, and this is an important
reason why nondormant seeds in the soil do not germi-
nate (Fenner and Thompson, 2005) . For nondormant
seeds on the soil surface, there arevarious factors that
may play a role in controllinggermination, i . e ., pro-
vide a signal that conditions are suitable for seedling
establishment . For example, light filtered through
green leaves (Teketay, 1998) or constant temperatures
(Pons and Schroder, 1986) may reduceor prevent ger-
mination of nondormant seeds, depending on the spe-
cies . For some species, there are chemical cues from
the environment that promote germination of nondor-
mant seeds . One example is seeds of Schoenoplectus
hallii which germinate in shallowpools of water in spri-
ng . Seeds must be cold stratified ( under moist but not
flooded conditions) to break PD, after which they
require flooding, exposure to high (30?15℃ ) tempera-
tures, light and ethylene to germinate ( Baskin et al. ,
2003) .
The many observationsof appearanceof thousands
of seedlings following fire, especially inmatorral vege-
tation, have prompted research to determine the effects
of heat and chemicals from fire on germination . de-
482 云 南 植 物 研 究 30 卷
Lange and Boucher ( 1990) were the first to find that
smoke fromburningplant material wouldpromotegerm-
ination, and subsequently smoke and smoke-water have
been used to promote seed germinationof many species
(Stevens et al. , 2007 ) . However, smoke or smoke-
water often is more effective in promoting germination
after seeds have been given a treatment to break PD,
e. g ., burial in soil and thus exposure to summer field
temperatures ( Baker et al. , 2005 ) , indicating that at
least in some species smoke promotes germination of
nondormant seeds and is a cue that the area has been
burned . The compound in smoke that promotes germi-
nation has been identified ( Flematti et al. , 2004 ) ,
and it is a butenolide which more specifically is known
as karrikinolide (Flematti et al. , 2007) .
Effects of animals
In addition to studies on seed predation and seed
dispersal by animals, much attention has been given to
effects of animals on germination of seeds that have
been regurgitated or passed through the digestive sys-
tem . The assumption often is made that seeds with PY
must pass through the digestive system of an animal to
germinate in nature . However, careful studies show
that dependingon plant species and on kindof animal ,
seeds with PY may ( 1) be digested, i . e ., destroyed
(Smit and Rethman, 1996 ) , ( 2 ) become permeable
and germinate in the digestive system and thus die
(Gardener et al. , 1993) , (3 ) germinateto higher per-
centages after they have been defecated than the non-
ingested controls (Shiferaw et al. , 2004 ) and (4 ) ex-
hibit no increase in germination after defecation ( Orte-
ga-Baes et al. , 2001) . The story for water-permeable
seeds that are eaten by animals is about the same . That
is, passage through the digestive system may increase
( Serio-Silva and Rico-Gray, 2002 ) , decrease
( Charalambidou et al. , 2005 ) or have no effect
(Figueroa and Castro, 2002 ) on germination percent-
ages, compared to those of control seeds . For many
species, however, removal of fruit material fromaround
seeds significantly increases germination ( Burrows,
1993) . Thus, in addition to seed dispersal , oneof the
big effectsof animals, especially birds, on seedgermi-
nation is that they remove fruit materials that may con-
tain germination inhibitors ( Traveset and Verdu,
2002) .
Desiccation sensitive seeds
All desiccation sensitive (recalcitrant) seeds have
a highmoisture content (30 - 70% ) at timeof dispers-
al , and they die if moisture content declines to < 15 -
40% , depending on the species . Also, seeds are sen-
sitive to low temperatures and die if frozen . In cont-
rast, orthodox seeds have a moisture content of 15 -
20% at maturity, can be dried to 6 - 12% and most
tolerate freezing ( Baskin and Baskin, 1998 ) . Desicca-
tion sensitive seeds are more likely to be found in spe-
cies living in moist, aseasonal habitats than in those
living in arid, seasonal habitats, but some arid-zone
species do havedesiccation sensitive seeds (Tweddle et
al. , 2003 ) . Overall , seeds of only a relatively small
proportion ( ca . 10% ) of seed plants are recalcitrant .
Somewhat surprising is that more than 90% of aquatic
and marsh species have orthodox seeds ( Dickie and
Pritchard, 2002) . However, due to thebigproblemof
trying to store recalcitrant seeds of economically-valu-
able species, especially trees, much ecological , bio-
chemical and ultrastructure research has been done on
themin the last 30 years .
Metabolism is continuous in recalcitrant seeds,
which helps to explain why they need to be continuous-
ly hydrated to prevent DNA damage and possible death
(Boubriak et al. , 2000 ) . In fact, some recalcitrant
seeds are dormant when they are dispersed and thus
must bekeptmoist during the timerequired for dorman-
cy break and for germination (Flores, 1996 ) . In Pana-
ma, desiccation-tolerant seeds aremore likely to bedis-
persed in thedry season, anddesiccation sensitiveseeds
are more likely to bedispersed in the wet season (Daws
et al. , 2005 ) . Attempts to store recalcitrant seeds for
extended periodsof time at highmoisture levels havenot
beenvery successful due to high susceptibility of seeds
to attack byfungi (Berjak et al. , 2004) , ineffectivemi-
crobial defense systems in the seeds (Anguelova-Merhar
et al. , 2003) and high possibility of seeds germinating
(Corbineau and Come, 1986) . At present, cryopreser-
vation ( < - 130℃ ) of seeds and zygotic embryos of re-
calcitrant species is receiving much attention . Methods
5823 期 BASKIN and BASKIN: Advances in Understanding Seed Dormancy at theWhole-seedLevel : An . . .
to dehydrate tissues to theglassy state usingvitrification
solutions (Fahy et al. , 2004) or to rapidly super-cool
them ( Wesley-Smith et al. , 2004) arebeing developed
as ways to safely cryopreserve recalcitrant seeds .
An important discoverywith regard to seed storage
is that some seeds are intermediate between orthodox
and recalcitrant in terms of tolerance to low moisture
levels and low temperatures ( Ellis et al. , 1991 ) . A
number of Citrus (Hong and Ellis, 1995) and Coffea
(Dussert et al. , 1999 ) species have seeds with inter-
mediate storage behavior . Berjak and Pammenter
( 2001) emphasizethat there is a continuumof sensitiv-
ities to dehydration between recalcitrant and orthodox
seeds, and even within seeds with intermediate storage
behavior there is a continuum .
Genetics
The inheritance of seed dormancy has received
much attention, especially with regard to rice ( Oryza
sativa) (Oard et al. , 2000; Gu et al. , 2004 ) but also
many other species ( Leon et al. , 2006a) . Quantitative
trait loci are thesubjectof intensestudy invarious spe-
cies ( Gu et al. , 2006; Bettey et al. , 2000 ) , while
genes that control various aspects of seed dormancy and
germination (FukuharaandBohnert, 2000) , especially
for Arabidopsis thaliana ( Chiwocha et al. , 2005;
Gonzalez et al. , 2004; Salaita et al. , 2005; Cadman
et al. , 2006; Finch-Savage et al. , 2007 ) are being
identified in other species . On the other hand, some
work is being done on the effects of the mother plant
( preconditioning) on dormancy and germination of
seeds, with particular focus on effects of precondition-
ing on characteristicsof the resulting seeds such as col-
or ( Luzuriaga et al. , 2006 ) , mass ( Luzuriaga et al. ,
2006; McPeek and Wang, 2007 ) , thickness of fruit?
seed (Qaderi et al. , 2003) and concentration of UV-
absorbing compounds (Griffen et al. , 2004) .
Inbreeding depression in plants is a topic of much
interest, and several hundred papers have been pub-
lished on thesubject in the last30 years . Froma seed-
germination perspective, if seeds resulting from selfed
flowers have lower germination than those from crossed
flowers this is interpreted to be evidence of inbreeding
depression . Although many cases of inbreedingdepres-
sion ( with respect to germination) have been found
(Galloway and Etterson, 2007) , often there is no evi-
dence of it ( Molina-Freaner et al. , 2003; Pico and
Koubek, 2003) .
Research on seed polymorphism continues and
studies can bedivided into two general categories: het-
erocarpy and size?mass . The dimorphic seeds of Aster-
aceae ( Gibson and Tomlinson, 2002; El-Keblawy,
2003; Brandel , 2007) and Chenopodiaceae ( Khan et
al. , 2004; Mandak and Pysek, 2005) and to a certain
extent Brassicaceae ( Cordazzo, 2006) and a few other
families ( Bandera and Traveset, 2006 ) have been
studied .The focus of these studieshasbeen to evaluate
the effects of polymorphism on germination, as well as
the adaptive significance and fitness .
Seed size?massmay have effects not only ongerm-
inationbut also on early growth and successful (or not)
establishment of seedlings (Khurana and Singh, 2004;
Moles and Westoby, 2004 ) and on evolutionary stable
strategies ( Rees and Venable, 2007 ) . The interest in
seed size continues to increase, and now divergence
analysis, using information for thousands of species, is
beingused toask what factors aremost closely associat-
ed with changes in seed mass . This analysis showed
that growth form and seed mass are closely related
(Moles et al. , 2005a, b) , and there is a close corre-
lation between seed mass and size of the genome
( Beauleu et al. , 2007) . Divergence in seed mass also
is related to other factors, such as temperature, precip-
itation and latitude (Moles et al. , 2005b) . On a glo-
bal scale, seed mass generally decreases with latitude,
but at20 - 25°(at theedgeof the tropics) there is a 7-
fold decrease inmass, seemingly correlated with differ-
ences in vegetation type and growth form of species
(Moles et al. , 2007) .
World biogeography of seed dormancy
A vast amount of information is available on pres-
ence vs . absence of dormancy and on class of seed
dormancy of plant species from throughout the world .
Further, new data from each of the major vegetation
zones recognized by Walter (1979) continueto bepub-
lished: evergreen rainforests ( Ferraz and Varla,
2003 ) , semievergreen rainforests ( Sautu et al. ,
682 云 南 植 物 研 究 30 卷
2007) , tropical montane ( Tigabu and Oden, 2001 ) ,
tropical deciduous forests ( Zamith and Scarano,
2004) , savannas ( Danthu et al. , 2003 ) , hot deserts
(Flores et al. , 2006 ) , matorral ( Cochrane et al. ,
2002) , broadleaved evergreen forests ( Chien et al. ,
2006) , deciduous forests ( Kondo and Sato, 2007 ) ,
steppes ( Wesche et al. , 2006 ) , cold deserts ( Ren
and Tao, 2004 ) , boreal forests ( Rosner and Har-
rington, 2004) , tundra ( Cummins and Miller, 2000)
and mountains (Phartyal et al. , 2003) . Thus, efforts
to compilethesedata and to begin to study general pat-
terns of the biogeography of dormancy are underway
( Baskin and Baskin, 1998 , unpubl .) .
Data on dormancy vs . nondormancy, and if
dormant the class of dormancy, for 7351 species have
been organized by vegetation zone . For all vegetation
zones except tropical rainforests and semievergreen
rainforests, more species have dormant than nondor-
mant seeds . In rainforests, 52% and 48% of the spe-
cies have nondormant and dormant seeds, respectively,
and in semievergreen rainforests 50% and 50% of the
species have nondormant and dormant seeds, respec-
tively ( Baskin and Baskin, unpubl .) . Generally, in
tropical?subtropical areas the portion of species with
dormant seeds increases across the gradient of vegeta-
tion zones as temperature and precipitation decrease . In
temperate?arctic areas, the portion of species with
dormant seeds increases across the gradient of vegeta-
tion zones as temperature and precipitation decrease
until one comes to the relatively cool vegetation zones
(woodland, montane, boreal and tundra) , where the
proportion of species with dormant seeds decreases
(Baskin and Baskin, 1998 , unpubl .) . PD ( 29 .8 -
79 .7% of the species) is the most important class of
dormancy in all vegetation zones on earth, with PY
(3 . 2 - 30 .0% ) and MPD (0 - 16.3% ) being second
and third in importance, respectively . MPD ( 0 -
3 .1% ) and (PY + PD) ( 0 - 2 .1% ) are not very im-
portant in any vegetation zone .
Phylogeny
The on-going process of updating and revising the
phylogeny of angiosperms ( APG, 2003 ) , as well as
improving phylogenies of various orders and families
means the opportunities to do seed dormancy studies in
a phylogenetic context are increasing . That is, germi-
nation studies done using members of a lineage could
provide new insight into the evolutionary relationships
of classes of dormancy ( or nondormancy) . Although
much research currently is being done on estimation of
divergence times and biogeography of various taxonomic
groups (Xiang et al. , 2004; Nie et al. , 2005) , infor-
mation on phylogeny has not yet been widely used to
help gain an understandingof evolutionary relationships
of seed dormancy . In one study, using four species in
a subclade of Aristolochia subgenus Siphisia, it was
found that both trait stasis and divergence (adaptation)
have occurred in dormancy-breaking and germination
requirements in this lineage ( Adams et al. , 2005 ) .
Further insights can be gained by combining informa-
tiononphylogeny, classesof dormancy ( or nondorman-
cy) and fossil history . For example, in the Dipsacales,
all the clades except themost advanced Valerina clade
have underdeveloped embryos and thus MD or MPD .
Members of the Valerina clade have seeds with fully
developed embryos and thus either PD or are nondor-
mant . The fossil record suggests that MPD or MD was
present in Dipsacales earlier than PD or nondormancy
( Baskin et al. , 2006) .
The future
It is clear that research on the ecology of seed
dormancy and germination already spans a broad spec-
trumof topics, but this spectrumwill , no doubt, con-
tinue to expand . Some topics, e. g ., the genetic as-
pects of the ecology of seed dormancy andgermination,
already shows signs of much diversification, including
effects of breeding system (Verdu et al. , 2004) , pop-
ulation size (Paschke et al. , 2002) , habitat fragment-
ation ( Cascante et al. , 2002 ) , herbicide resistance
( Recasens et al. , 2007 ) and phenotypic plasticity
(Donohue, 2005 ) on germination and fitness; pro-
teomics ( Leon et al. , 2005b) ; and spread of trans-
genes into wild populations ( Garnier and Lecomte,
2006) ; invasive vs . non-invasive species ( Mandak,
2003) ; and rare vs . common species ( Osunkoya and
Swanborough, 2001) .
7823 期 BASKIN and BASKIN: Advances in Understanding Seed Dormancy at theWhole-seedLevel : An . . .
We foresee that the determination of class of
dormancy (or nondormancy) , as well as the dormancy-
breaking andgermination requirementsof seeds fromall
over the world will continue at a rapid rate . Thestimu-
lus for this work comes fromthe desireof many scienti-
sts to know how things work in nature and from the
need for information on how to propagate species for
economic and conservation reasons . As information on
( 1 ) seed dormancy class ( or nondormancy ) and
dormancy-breaking and germination requirements in-
creases for plant taxa from all vegetation zones of the
world, and ( 2) phylogenetic relationshipswithinorders
and families are increasingly refined ( using both DNA
and fossil evidence) , good tools with which to under-
take studies of evolutionary relationships of seed
dormancy andgermination within plant lineages will be
available . Thus, major advancements inour knowledge
of theworldbiogeography of seeddormancy and of evo-
lutionary origins and relationships of thevarious classes
of dormancy (and nondormancy) can be expected .
References:
Adam ?s CA, Baskin JM, Baskin CC , 2005 . Trait stasis versus adaptation
in disjunct relict species: Evolutionary changes in seed dormancy-
breaking and germination requirements in a subclade of Aristolochia
subgenus Siphisia ( Piperales) [ J ] . Seed Sci Res, 15 : 161—173
Adki #ns SW, Loewen M , Symons SJ , 1986 . Variation within pure lines of
wild oats ( Avena fatua) in relation to degree of primary dormancy
[ J ] . Weed Sci , 34 : 859—864
Angi ?ospermPhylogeny Group ( APG ) , 2003 . An update of the Angio-
spermPhylogeny Group classification for the orders and families of
flowering plants: APG II [ J ] . Bot J Linn Soc, 141: 399—436
Angu /elova-Merhar VS, Calistru C, Berjak P, 2003 . A study of somebio-
chemical and histopathological responses of wet-stored recalcitrant
seeds of Avicennia marina infected by Fusarium moniliforme [ J ] .
Ann Bot, 92 : 401—408
Anto ?novics J , Schmitt J , 1986 . Paternal and maternal effects on
propagule size in Anthoxanthum odoratum [ J ] . Oecologia , 69 :
277—282
Arro ?yo MTK , Cavieres LA , Humana AM , 2004 . Experimental evidence
of potential for persistent seed bank formation at a subantarctic alpine
site in Tierra del Fuego, Chile [ J ] . Ann Missouri Bot Gard, 91 :
357—365
Auld 7TD, Scott J , 2004 . Estimating population abundance in plant spe-
cies with dormant life-stages: Fire and the endangered plant Gre-
villea caleyi R . Br [ J ] . Ecol Manage Restor, 5 : 125—129
Bake r KS, SteadmanKJ , Plummer JA et al. , 2005 . Dormancy release in
Australian fire ephemeral seeds during burial increases germination
response to smoke water or heat [ J ] . Sci Sci Res, 15 : 339—348
Band ?era MC, Traveset A , 2006 . Reproductive ecology of Thymelaea ve-
lutina ( Thymelaeaceae ) -factors contributing to the maintenance of
heterocarpy [ J ] . Plant Syst Evol, 256: 97—112
Bart ?on LV , 1930 . Hastening the germination of some coniferous seeds
[ J ] . Amer J Bot, 17 : 88—115
Bask ?in CC , Baskin JM , 1998 . Seeds: Ecology, biogeography, and evo-
lution of dormancy and germination [ M ] . San Diego: Academic
Press
Bask ?in CC , Baskin JM, 2005 . Underdeveloped embryos in dwarf seeds
and implications for assignment to dormancy class [ J ] . Seed Sci Res,
15 : 357—360
Bask ?in CC , Baskin JM , 2007 . A revision of Martin′s seed classification
system, with particular reference to his dwarf-seed type [ J ] . Seed
Sci Res, 17 : 11—20
Bask ?in CC , Baskin JM , Chester EW et al. , 2003 . Ethylene asa possible
cue for seed germination of Schoenoplectus hallii ( Cyperaceae) , a
rare summer annual of occasionally flooded sites [ J ] . Amer J Bot,
90 : 620—627
Bask ?in CC, Baskin JM, Yoshinaga A , 2005 . Morphophysiological
dormancy in seeds of six endemic lobelioid shrubs (Campanulaceae)
from the montane zone in Hawaii [ J ] . Can J Bot, 83 : 1630—1637
Bask ?in CC , Baskin JM, Yoshinaga A et al. , 2005 . Germination of
drupelets in multi-seeded drupes of the shrub Leptecophylla tame-
iameiae ( Ericaceae) from Hawaii: A case for deep physiological
dormancy broken by high temperatures [ J ] . Seed Sci Res, 15 :
349—356
Bask ?in JM , Baskin CC, 1971 . Effect of chilling and gibberellic acid on
growth potential of excised embryos of Ruellia humilis [ J ] . Planta,
100: 365—369
Bask ?in JM , Baskin CC , 1985a . Does seed dormancy play arole in germi-
nation ecology of Rumex crispus ? [ J ] . Weed Sci , 33 : 340—343
Bask ?in JM, Baskin CC , 1985b . The annual dormancy cycle in buried
weed seeds: A continuum [ J ] . BioScience, 35 : 492—498
Bask ?in JM, Baskin CC , 1990 . Germination ecophysiology of seeds of the
winter annual Chaerophyllumtainturieri : A new typeof morphophysi-
ological dormancy [ J ] . J Ecol , 78 : 993—1004
Bask ?in JM , Baskin CC , 2000 . Evolutionary considerations of claims for
physical dormancy-break by microbial action and abrasion by soil par-
ticles [ J ] . Seed Sci Res, 10 : 409—413
Baskin JM, Baskin CC , 2004 . A classification systemfor seed dormancy
[ J ] . Seed Sci Res, 14 : 1—16
Bask ?in JM, Baskin CC, Dixon KW, 2006 . Physical dormancy in the en-
demic Australian genus Stylobasium, afirst report for the family Suri-
anaceae ( Fabales) [ J ] . Seed Sci Res, 16 : 229—232
Bask ?in JM, Baskin CC , Li X , 2000 . Taxonomy, anatomy and evolution
of physical dormancy in seeds [ J ] . Plant Species Biol , 15 : 139—
152
Bask ?in JM, Hidayati SN , Baskin CC et al. , 2006 . Evolutionary consid-
erations of the presence of both morphological and physiological seed
dormancy in the highly advanced euasterids I I order Dipsacales [ J ] .
Seed Sci Res, 16 : 233—242
882 云 南 植 物 研 究 30 卷
Batl ?laD, Benech-Arnold RL , 2005 . Changes in the light sensitivity of
buried Polygonumaviculare seeds in relation to cold- induced dorman-
cy loss: Development of a predictive model [ J ] . New Phytol, 165:
445—452
Beau lieu JM, Moles AT , Leitch IJ et al. , 2007 . Correlated evolution of
genome size and seed mass [ J ] . New Phytol , 173: 422—437
Bekk +er RM, Bakker JP, Grandin U et al. , 2001 . Light and temperature
dependence for germination and emergence of white horehound
( Marrubium vulgareL .) seeds [ J ] . Seed Technol, 23 : 139—144
Berj ?ak P , Kioko J I , Makhathini A et al. , 2004 . Strategies for field col-
lection of recalcitrant seeds and zygotic embryonic axes of the tropical
tree, Trichilia dregeana Sond [ J ] . Seed Sci Technol , 32 : 825—836
Berj ?ak P, Pammenter NW, 2001 . Seed recalcitrance-current perspectives
[ J ] . S Afr J Bot, 67 : 79—89
Bett ?ey M , Finch-Savage WE , King GJ et al. , 2000 . Quantitativegenetic
analysis of seed vigour and pre-emergence seedling growth traits in
Brassica oleracea [ J ] . New Phytol, 148: 277—286
Bidw (ell S, Attiwill PM, Adams MA, 2006 . Nitrogen availability and
weed invasion in aremnant nativewoodland in urban Melbourne [ J ] .
Aust Ecol , 31 : 262—270
Boub +riak I , Dini M , Berjak P et al. , 2000 . Desiccation and survival in
the recalcitrant seeds of Avicennia marina: DNA replication, DNA
repair and protein synthesis [ J ] . Seed Sci Res, 10 : 307—315
Bran ?del M , 2007 . Ecology of achene dimorphism in Leontodon saxatilis
[ J ] . Ann Bot, 100: 1189—1197
Bren ?chley WE, Warington K , 1936 . Theweed seed population of arable
soil . II I . There-establishment of weed species after reduction by fal-
lowing [ J ] . J Ecol , 24 : 479—501
Brow (n JS, VenableDL , 1991 . Lifehistory evolution of seed-bank annuals
in response to seed predation [ J ] . Evol Ecol , 5 : 12—29
Bulm /er MG, 1984 . Delayed germination of seeds: Cohen′s model revisit-
ed [ J ] . Theor Pop Biol , 26 : 367—377
Burr ?ows CJ , 1993 . Germination requirementsof the seeds of native trees,
shrubs and vines [ J ] . Canterbury Bot Soc J , 27 : 42—48
Cadm ;an CSC, Toorop PE, Hilhorst HWM et al. , 2006 . Gene expression
profiles of Arabidopsis Cvi seeds during dormancy cycling indicate a
common underlying dormancy control mechanism [ J ] . Plant J , 46 :
805—822
Carp ?ita NC, Sharia A , Barnett JP et al. , 1983 . Cold stratification and
growth of radiclesof loblolly pine ( Pinustaeda) embryos [ J ] . Phys-
iol Plant, 59 : 601—606
Casc ?ante A , Quesda M, Lobo JJ et al. , 2002 . Effects of dry tropical for-
est fragmentation on the reproductive success and genetic structure of
the tree Samanea saman [ J ] . Conserv Biol , 16 : 137—147
Char ?alambidou I , Santamaria L , Jansen C et al. , 2005 . Digestive plas-
ticity in mallard ducks modulates dispersal probabilities of aquatic
plants and crustaceans [ J ] . Funct Ecol , 19 : 513—519
Chen =F , Dahal P, Bradford KJ , 2001 . Two tomato expansin genes show
divergent expression and localization in embryos during seed devel-
opment and germination [ J ] . Plant Physiol , 127 : 928—936
Chen ?SSC , 1968 . Germination of light-inhibited seed of Nemophila insig-
nis [ J ] . Amer J Bot, 55 : 1177—1183
Chien CT , Chen SY , ChangSH et al. , 2006 . Dormancy and germination
in seeds of the medicinal Asian tree species Phellodendron amurense
var. wilsonii ( Rutaceae) [ J ] . Seed Sci Technol , 34 : 561—571
Chiw ?ocha SDS, Cutler AJ , Abrams SR et al. , 2005 . The etr 1-2 muta-
tion in Arabidopsis thaliana affects the abscisic acid, auxin, cytoki-
nin and gibberellin metabolic pathways during maintenance of seed
dormancy, moist-chilling and germination [ J ] . Plant J , 42 : 35—
48
Coch ?raneA , Kelly A , Brown K et al. , 2002 . Relationships between seed
germination requirements and ecophysiological characteristics aid the
recovery of threatened nativeplant species inWestern Australia [ J ] .
Ecol Manage Restor, 3 : 47—60
Cohen D, 1968 . A general model of optimal reproduction in a randomly
varying environment [ J ] . J Ecol , 56 : 219—228
Colbach N , Duerr C , Roger-Estrade J et al. , 2005 . How to model the
effects of farming practices on weed emergence [ J ] . Weed Res, 45 :
2—17
Corb ?ineau F , Come D, 1986 . Experiments on the storage of seeds and
seedlings of Symphonia globulifera L . f . ( Guttiferae) [ J ] . Seed Sci
Technol , 14 : 585—591
Cord ?azzo CV , 2006 . Seed characteristics and dispersal of dimorphic fruit
segments of Cakile maritima Scopoli ( Brassicaceae) population of
southern Brazilian coastal dunes [ J ] . Rev Brasil Bot, 29 : 259—265
Courtney AD, 1968 . Seed dormancy and field emergence in Polygonum
aviculare [ J ] . J Appl Ecol , 5 : 675—684
Cowling RM, Lamont BB , Pierce SM, 1987 . Seed bank dynamics of four
co-occurring Banksia species [ J ] . J Ecol , 75 : 289—302
Croc ?ker W, 1916 . Mechanisms of dormancy in seeds [ J ] . Amer J Bot,
3 : 99—120
Croc ?ker W, Barton LV , 1957 . Physiology of Seeds [ M ] . Waltham:
Chronica Botanica Co ., MA
Cumm ?ins RP, Miller GR , 2000 . Theroleof chilling in thegermination of
some Scottish montane species [ J ] . Bot J Scotl , 52 : 171—185
D′An ?gela E , Facelli JM , Jacobo E, 1988 . Theroleof thepermanent soil
seed bank in early stages of a post-agricultural succession in the in-
land Pampa, Argentina [ J ] . Vegetatio, 74 : 39—45
Dant ?hu P, Ndongo M, Diaou M et al. , 2003 . Impact of bush fireon ger-
mination of someWest African acacias [ J ] . For Ecol Manage, 173:
1—10
Darw ?in C, 1859 [ 1892] . Theorigin of species . 6th edition . D . Appleton
and Co ., New York
Daws MI , GarwoodNC , Pritchard HW, 2005 . Traitsof recalcitrant seeds
in a semi-deciduous tropical forest in Panama: Some ecological im-
plications [ J ] . Funct Ecol , 19 : 874—885
de Lange JH , Boucher C, 1990 . Autecological studies on Audouinia cap-
itata (Bruniaceae) . I . Plant-derived smoke as a seed germination
cue [ J ] . S Afr J Bot, 56 : 700—703
Dick ?ie JB, Pritchard HW, 2002 . Systematic and evolutionary aspects of
desiccation tolerance in seeds [ A ] . In: Black M, Pritchard HW
eds ., Desiccation and Survival in Plants: Drying without Dying
[M ] . CABI Wallingford, UK , 239—259
Dono ?hue K , 2005 . Seeds and seasons: Interpreting germination timing in
9823 期 BASKIN and BASKIN: Advances in Understanding Seed Dormancy at theWhole-seedLevel : An . . .
the field [ J ] . Seed Sci Res, 15 : 175—187
Duss !ert S, ChabrillangeN , Engelmann F et al. , 1999 . Quantitative esti-
mation of seed desiccation sensitivity using aquantal response model :
Application to nine species of the genus Coffea L . [ J ] . Seed Sci
Res, 9 : 135—144
Ekel ?eme F , Forcella F , Archer DW et al. , 2005 . Seedling emergence
model for tropic ageratum ( Ageratum conyzoides ) [ J ] . Weed Sci ,
53 : 55—61
El-K ?eblawy A , 2003 . Effects of achene dimorphism on dormancy and
progeny traits in the two ephemerals Hedypnois cretica and Crepis as-
pera ( Asteraceae) [ J ] . Can J Bot, 81 : 550—559
Ellis RH , Hong TD, Roberts EH , 1991 . An intermediate category of
seed storage behaviour ? II . Effects of provenance, immaturity, and
imbibition on desiccation- tolerance in coffee [ J ] . J Exp Bot, 42 :
653—657
Even ari M, 1980?81 . The history of germination research and the lesson it
contains for today [ J ] . Israel J Bot, 29 : 4—21
Fahy 5GM , Wowk B, Wu J et al. , 2004 . Improved vitrification solutions
based on the predictability of vitrification solution toxicity [ J ] .
Cryobiology, 48 : 22—35
Fenn &er M, Thompson K , 2005 . The Ecology of Seeds [M ] . Cambridge:
Cambridge University Press, UK
Fern ?andez RJ , Golluscio RA , Bisigato AJ et al. , 2002 . Gap colonization
in the Patagonian semidesert: Seed bank and diaspore morphology
[ J ] . Ecography, 25 : 336—344
Ferr ?az IDK , Varela VP, 2003 . Temperature otima para a germinacao das
sementes de trinta especies florestais da Amazonia [A ] . In: Higuchi
N et al. ( organizers) . Projecto J acaranda . Fase II : Pesquisas flo-
restais naAmazonia Central [ M] . Coordenacao de PesquisasemSilvi-
cultura Tropical , Instituto Nacional dePesquisas daAmazonia, Mana-
us, 117—127
Figu ?eroa JA , Castro SA , 2002 . Effectsof bird ingestion on seed germina-
tion of four woody species of the temperaterainforest of Chiloe Island,
Chile [ J ] . Plant Ecol , 160 : 17—23
Finc ?h-SavageWE , Cadman CSC, Toorop PE et al. , 2007 . Seed dorman-
cy release in Arabidopsis Cvi by dry afterripening, low temperature,
nitrate and light shows common quantitative patterns of gene expres-
sion directed by environmentally specific sensing [ J ] . Plant J , 51 :
60—78
Flem &atti GR , Ghisalberti EL , Dixon KW et al. , 2004 . A compoundfrom
smoke that promotes seed germination [ J ] . Science, 305: 977
Flem &atii G, Goddard-Borger E, Heath C et al. , 2007 . Investigation of
germination-promoting compounds in smoke . International Plant
Growth Substance Association . Puerto Vallarta, Mexico . Abstract
number MS804
Flor ?es EM , 1996 . Recalcitrant tree seed species of socioeconomic impor-
tance in Costa Rica: Stateof knowledgeof physiology [ A ] . In: Oue-
draogo AS, Poulsen K , Stubsgaard F eds ., Intermediate?recalcitrant
tropical forest tree seeds [ M ] . International Plant Genetic Resources
Institute, Rome and DANIDA Forest Seed Centre, Humlebaek, Den-
mark, 136—140
Flor ?es J , Jurado E , Arredondo A , 2006 . Effect of light on germination of
seeds of Cactaceae from the Chihuahuan Desert, Mexico [ J ] . Seed
Sci Res, 16 : 149—155
Forb ?is TA , Floyd SK , deQueiroz A , 2002 . The evolution of embryo size
in angiosperms and other seed plants: Implications for the evolution of
seed dormancy [ J ] . Evolution, 56 : 2112—2125
Fukuhara T , Bohnert HJ , 2000 . The expression of the Vp1- likegene and
seed dormancy in Mesembryanthemumcrystallinum [ J ] . Genes Genet
Syst, 75 : 203—209
Funes G, Basconcelo S, Diaz S et al. , 1999 . Seed bank dynamicsof La-
chemilla pinnata (Rosaceae) in different plant communities of moun-
tain grasslands in central Argentina [ J ] . Ann Bot Fen , 36 : 109—
114
Gall ?oway LF , Etterson J R, 2007 . Inbreeding depression in an autotetra-
ploid herb: A three cohort field study [ J ] . New Phytol , 173: 383—
392
Gard ?ener CJ , McIvor JG, Jansen A , 1993 . Passage of legume and grass
seeds through the digestive tract of cattle and their survival in feces
[ J ] . J Appl Ecol , 30 : 63—74
Garn ?ier A , Lecomte J , 2006 . Using a spatial and stage-structured model
to assess the spread of feral populations of transgenic oilseed rape
[ J ] . Ecol Model , 194: 141—149
Gibs ?on JP, Tomlinson AD, 2002 . Genetic diversity and mating system
comparisons between ray and disk achene seed pools of the hetero-
carpic species Heterotheca subaxillaris ( Asteraceae) [ J ] . Int J Plant
Sci , 163: 1025—1034
Gonzalez G, Abia D, Salinas J et al. , 2004 . Two new alleles of the ab-
scisic aldehyde oxidase 3 gene reveal its role in abscisic acid biosyn-
thesis in seeds [ J ] . Plant Physiol , 135: 325—333
Grif ?fen LR , Wilczek AM, Bazzaz FA , 2004 . UV-B affects within-seed
biomass allocation and chemical provisioning [ J ] . New Phytol , 162:
167—171
Grime JP, 1981 . The roleof seed dormancy in vegetation dynamics [ J ] .
Ann Appl Biol , 98 : 555—558
Groo ?t SPC , Karssen CM, 1987 . Gibberellins regulateseed germination in
tomato by endosperm weakening: A study with gibberellin-deficient
mutants [ J ] . Planta, 171: 525—531
Groo ?tjen CJ , Bouman F , 1988 . Seed structure in Cannaceae: Taxonomic
and ecological implications [ J ] . Ann Bot, 61 : 363—371
Grun ?dy AC , Mead A , Burston S , 2003 . Modelling the emergence re-
sponseof weed seeds to burial depth: Interactionswith seed density,
weight and shape [ J ] . J Appl Ecol , 40 : 757—770
Grus ?hvitzky IV , 1967 . After-ripening of seedsof primitive tribesof angio-
sperms, conditions and peculiarities [ A ] . In: Borris H ed ., Physi-
ologie, Okologieund Biochemie der Keimung [ M ] . Vol . 1 . Greif-
swald: Ernst-Moritz-Arndt Universitat, 329—336 , 8 figures
Gu XY , Kianian SF , Foley ME, 2004 . Multiple loci and epistases con-
trol genetic variation for seed dormancy in weedy rice ( Oryza sativa)
[ J ] . Genetics, 166: 1503—1516
Gu X ?Y , Kianian SF , Foley ME, 2006 . Isolation of threedormancy QTLs
as Mendelian factors in rice [ J ] . Heredity, 96 : 93—99
Gutt ?erman Y , 1981 . Influenceof quantity and dateof rain on thedispers-
al and germination mechanisms, phenology, development and seed
092 云 南 植 物 研 究 30 卷
germinability in desert annual plants, and on the life cycle of geo-
phytes and hemicryptophytes in the Negev desert [ A ] . In: Shuval H
ed ., Developments in arid zone ecology and environmental quality
[M ] . Balaban ISS, Philadelphia
Gutt ?erman Y , Porath D, 1975 . Influences of photoperiodism and light
treatments during fruit storage on the phytochrome and on the germi-
nation of CucumisprophetarumL . and Cucumissativus L . seeds [ J ] .
Oecologia, 18 : 37—43
Hack .er JB, Ratcliff D, 1989 . Seed dormancy and factors controlling
dormancy breakdown in buffel grass accessions from contrasting prov-
enances [ J ] . J Appl Ecol , 26 : 201—212
Harp &er JL , Obeid M , 1967 . Influenceof seed size and depth of sowing on
the establishment and growth of varieties of fiber and oil seed flax
[ J ] . Crop Sci , 7 : 527—532
Hoel ?zel N , Otte A , 2003 . Restoration of a species-rich flood meadow by
topsoil removal and diaspore transfer with plant material [ J ] . Appl
Veg Sci , 6 : 131—140
Hone .k A , Martinkova Z, J aroski V , 2003 . Ground beetles ( Carabidae)
as seed predators [ J ] . Eur J Ent, 100: 531—544
Hong ATD, Ellis RH , 1995 . Interspecific variation in seed storage behav-
iour within two genera- Coffea and Citrus [ J ] . Seed Sci Technol ,
23 : 165—181
J ana (A , Acharya SN, Naylor JM, 1979 . Dormancy studies in seed of
Avena fatua . 10 . On the inheritanceof germination behaviour [ J ] .
Can J Bot, 57 : 1663—1667
J aya ?suriya KMGG, Baskin JM , Baskin CC , 2007 . Morphology and anato-
my of physical dormancy in Ipomoea lacunosa: Identification of the
water gap in seeds of Convolvulaceae ( Solanales ) [ J ] . Ann Bot,
100: 13—22
J aya ?suriyaKMGG, Baskin JM, Baskin CC , 2008 . Cycling of sensitivity
to physical dormancy-break in seeds of Ipomoea lacunosa ( Convolvu-
laceae) and ecological significance [ J ] . Ann Bot, 100: 341—352
J unt ?tila O, 1971 . Effect of mother plant temperatureon seed development
and germination in Syringa reflexa Schneid [ J ] . Meld Norges Land-
bruk Shogsk, 50 : 1—16
J unt ?tila O, 1973 . The mechanism of low temperature dormancy in mature
seeds of Syringa species [ J ] . Physiol Plant, 29 : 256—263
Kala ?mees R , Zobel M, 2002 . The roleof the seed bank in gap regenera-
tion in a calcareous grassland community [ J ] . Ecology, 83 : 1017—
1025
Khan CAA , Karssen CM, 1980 . Induction of secondary dormancy in Che-
nopodiumbonus-henricus L . seeds by osmotic and high temperature
treatments and its prevention by light and growth regulators [ J ] .
Plant Physiol , 66 : 175—181
Khan BMA , Gul B, Weber DJ , 2004 . Temperature and high salinity ef-
fects in germinating dimorphic seedsof Atriplexrosea [ J ] . W North
Amer Nat, 64 : 193—201
Khur ana E , Singh JS, 2004 . Germination and seedling growth of five tree
species from tropical dry forest in relation to water stress: Impact of
seed size [ J ] . J Trop Ecol , 20 : 385—396
Koll ?er D, 1955 . Germination regulating mechanisms in some desert
seeds . I [ J ] . Bull Res Counc Israel ( D) , 4 : 381—387
Kond ?o T, Sato C , 2007 . Effects of temperature, light, storage condi-
tions, sowing time, and burial depth on the seed germination of Car-
diocrinum cordatum var. glehnii ( Liliaceae) [ J ] . Landscape Ecol
Eng, 3 : 89—97
Lamont BB , 1991 . Canopy seed storage and release-what′s in a name ?
[ J ] . Oikos, 60 : 266—268
Leon ?RG, Bassham DC , Owen MDK , 2006a . Inheritance of deep seed
dormancy and stratification-mediated dormancy alleviation in Ama-
ranthus tuberculatus [ J ] . Seed Sci Res, 16 : 193—202
Leon ?RG, BasshamDC , Owen MDK , 2006b . Germination and proteome
analyses reveal intraspecific variation in seed dormancy regulation in
common waterhemp ( Amaranthus tuberculatus) [ J ] . Amer J Bot,
86 : 1505—1511
Li X ?, Baskin JM , Baskin CC , 1999 . Anatomy of two mechanisms of
breaking physical dormancy by experimental treatments in seeds of
two North American Rhus species (Anacardiaceae) [ J ] . Weed Sci ,
54 : 305—315
Luzu ?riaga AL , Escudero A , Perez-GarciaF , 2006 . Environmental mater-
nal effects on seed morphology and germination in Sinapis arvensis
(Cruciferae) [ J ] . Weed Res, 46 : 163—174
Mand ?ak B , 2003 . Germination requirements of invasive and non-invasive
Atriplex species: A comparative study [ J ] . Flora, 198 : 45—54
Mand ?ak B, Pysek P, 2005 . How does seed heteromorphism influence the
life history stages of Atriplex sagittata ( Chenopodiaceae) ? [ J ] .
Flora , 200: 516—526
Martin AC, 1946 . The comparative internal morphology of seeds [ J ] .
Amer Midl Nat, 36 : 513—660
Mas ?MT, Verdu AMC , 2002 . Effects of thermal shocks on the germina-
tion of Amaranthus retroflexus . Useof the EXCEL Solver tool tomod-
el cumulative germination [ J ] . Seed Sci Technol , 30 : 299—310
McCu ?llough JM , Shropshire W, Jr, 1970 . Physiological predetermination
of germination responses in Arabidopsis thaliana ( L .) Heynh [ J ] .
Plant Cell Physiol , 11 : 139—148
McPe ?ek TM, Wang X, 2007 . Reproduction of dandelion ( Taraxacumof-
ficinale) in a higher CO2 environment [ J ] . Weed Sci , 55 : 334—
340
Mell ?a AR , Burgin MJ , Sanchez RA , 2004 . Expansin gene expression in
Datura ferox L . seeds is regulated by the low-fluence response, but
not by the high-irradiance response, of phytochromes [ J ] . Seed Sci
Res, 14 : 61—71
Meng ?istu T, Teketay D, HultenH et al. , 2005 . Theroleof enclosures in
the recovery of woody vegetation in degraded dryland hillsides of cen-
tral and northern Ethiopia [ J ] . J Arid Environ, 60 : 259—281
Meye ?r SE , 1990 . Seed sourcedifferences in germination under snowpack
in northern Utah [ A ] . In: Proc . Fifth Billings Symposium on Dis-
turbed land reclamation, Volume 1 [ M ] . Montana: Montana State
University Reclamation Research Unit, Bozeman, 184—191
Mole ?s AT , Ackerly DD, Webb CO et al. , 2005a . A brief history of seed
size [ J ] . Science, 307: 576—580
Mole ?s AT , Ackerly DD, Webb CO et al. , 2005b . Factors that shape
seed mass evolution [ J ] . Proc Nat Acad Sci USA, 102: 10540—
10544
1923 期 BASKIN and BASKIN: Advances in Understanding Seed Dormancy at theWhole-seedLevel : An . . .
Mole #s AT, Ackerly DD, Webb CO et al. , 2007 . Global patterns in seed
size [ J ] . Global Ecol Biogeogr, 16 : 109—116
Mole #s AT, Westoby M, 2004 . Seed mass and seedling establishment after
fire in Ku-ring-gai Chase National Park, Sydney, Australia [ J ] .
Aust Ecol , 29 : 383—390
Moli ?na-Freaner F , Cervantes-Salas M , Moralea-Romero D et al. , 2003 .
Does thepollinator abundance hypothesis explain geographic variation
in thebreeding system of Pachycereuspringlei ? [ J ] . Int J Plant Sci ,
164: 383—303
Nand /i OL , 1998 . Ovule and seed anatomy of Cistaceae and related Mal-
vanae [ J ] . Plant Syst Evol , 209: 239—264
Negb +i M, Tamari B, 1963 . Germination of chlorophyllous and achloro-
phyllous seeds of Salsola volkensii and Aellenia autrani [ J ] . Israel J
Bot, 12 : 124—135
Nels ?on J R , Harris GA , Goebel CJ , 1970 . Genetic vs . environmentally
induced variation in medusahead ( Taeniatherum asperum (Simonkai)
Nevski) [ J ] . Ecology, 51 : 526—529
Newm Han EI , 1963 . Factors controlling thegermination date of winter an-
nuals [ J ] . J Ecol , 51 : 625—638
Ng F -SP , 1991 .Manual of Forest Fruits, Seeds and Seedlings [M ] . Vol .
1 . Kuala Lumpur: Forest Research Institute Malaysia
Ng F -SP , 1992 .Manual of Forest Fruits, Seeds and Seedlings [M ] . Vol .
2 . Kuala Lumpur: Forest Research Institute Malaysia
Nie ?ZL , Wen J , Sun H et al. , 2005 . Monophyly of Kelloggia Torrey ex
Benth . ( Rubiaceae) and evolution of its intercontinental disjunction
betweenwestern North America and eastern Asia [ J ] . Amer J Bot,
92 : 642—652
Niko ?laeva MG, 1969 . Physiology of Deep Dormancy inSeeds [M ] . Len-
ingrad, Russia, Izdatel′stovo‘Nauka’. (Translated from Russian by
Z . Shapiro, National Science Foundation, Washington, DC .)
Niko ?laeva MG, 1977 . Factors controlling the seed dormancy pattern [A ] .
In: Khan AA ed ., ThePhysiology and Biochemistry of SeedDorman-
cy and Germination [M ] . Amsterdam, North-Holland, 51—74
Niko ?laeva MG, 1999 . Patterns of seed dormancy and germination as relat-
ed to plant phylogeny and ecological and geographical conditions of
their habitats [ J ] . Russian J Plant Physiol ( Fiziologiya Rastenii) ,
46 : 369—373
Niko ?laeva GG, 2001 . Ecological and physiological aspects of seed
dormancy and germination ( review of investigations for the last centu-
ry) [ J ] . Bot Zhur, 86 : 1—14 ( in Russian with English summary)
Niko ?laeva MG, 2004 . On criteria to use in studies of seed evolution [ J ] .
Seed Sci Res, 14 : 315—320
Oard 3J , Cohn MA , Linscombe S et al. , 2000 . Field evaluation of seed
production, shattering, and dormancy in hybrid populations of trans-
genic rice ( Oryza sativa) and the weed, red rice ( Oryza sativa)
[ J ] . Plant Sci , 157: 13—22
Olso ?n DS, 1932 . Germinative capacity of seed produced from young trees
[ J ] . J For, 30 : 871
Orte ?ga-Baes P, de Viana ML , Larenas G et al. , 2001 . Germinacion de
semillas de Caesalpinia paraguariensis ( Fabaceae) : Agentes escarifi-
cadores y efecto del ganado [ J ] . Rev Biol Trop, 49 : 301—304
Osun *koya OO, Swanborough PW, 2001 . Reproductive and ecophysiologi-
cal attributesof the rare Gardenia actinocarpa ( Rubiaceae) compared
with its common co-occurring congener, G. ovularis [ J ] . Aust J
Bot, 49 : 471—478
Pake ?man RJ , Small JL , 2005 . The role of the seed bank, seed rain and
the timing of disturbance in gap regeneration [ J ] . J Veg Sci , 16 :
121—130
Pall ?as JE, Jr, Stansell JR , Bruce RR , 1977 . Peanut seed germination as
related to soil water regime during pod development [ J ] . Agron J ,
69 : 381—383
Pasc ?hke M, Abs C, Schmid B , 2002 . Effectsof population size and pol-
len diversity on reproductive success and offspring size in the narrow
endemic Cochlearia bavarica (Brassicaceae) [ J ] . Amer J Bot, 89 :
1250—1259
Phar ?tyal SS, Thapliyal RC , Nayal JS et al. , 2003 . The influences of
temperatures on seed germination rate inHimalayan elm ( Ulmus wal-
lichiana) [ J ] . Seed Sci Technol , 31 : 83—93
Phil ?ippi T , Seger J , 1989 . Hedging one′s evolutionary bets, revisited
[ J ] . Trends Ecol Evol , 4 : 41—44
Pico ?FX , Koubek T, 2003 . Inbreeding effects on fitness traits in the het-
erocarpic herb Leontodon autumnalis L . ( Asteraceae) [ J ] . Acta
Oecol , 24 : 289—294
Pons ?TL , Schroder HFJM, 1986 . Significance of temperature fluctuation
and oxygen concentration for germination of therice field weeds Fim-
bristylis littoralis and Scirpus juncoides [ J ] . Oecologia , 68 : 315—
319
Qade ?ri MM , Cavers PB , Bernards MA , 2003 . Pre- and post-dispersal
factors regulate germination patterns and structural characteristics of
Scotch thistle ( Onopordum acanthium) cypselas [ J ] . New Phytol ,
159 : 263—278
Quin ?livan BJ , 1961 . The effect of constant and fluctuating temperatures
on the permeability of the hard seeds of some legume species [ J ] .
Aust J Agric Res, 12 : 1009—1022
Quin ?n JA , Colosi JC , 1977 . Separating genotype from environment in
germination ecology studies [ J ] . Amer Midl Nat, 97 : 484—489
Ratc ?liffe D, 1961 . Adaptation to habitat in agroup of annual plants [ J ] .
J Ecol , 49 : 187—203
Reca ?sens J , Caimons O, Torra J et al. , 2007 . Variation in seed germina-
tion and early growth between andwithin acetolactate synthaseherbi-
cide resistant and susceptible Lolium rigidum accessions [ J ] . Seed
Sci Technol , 35 : 32—47
ReesM, Venable DL , 2007 . Why do big plants make big seeds ? [ J ] . J
Ecol , 95 : 926—936
Ren ?J , Tao L , 2004 . Effects of different pre-sowing seed treatments on
germination of 10 Calligonum species [ J ] . For Ecol Manage, 195:
291—300
Robe ?rts EH , 1972 . Dormancy: A factor affecting seed survival in the soil
[ A ] . In: Roberts EH ed ., Viability of Seeds [ M] . SyracuseUniv .
Press, Syracuse, NY , 321—357
Roberts HA , 1981 . Seed banks in soils [ J ] . AdvAppl Biol , 6 : 1—55
Rodr ?igues-daSilvaUDS, Matos DMDS, 2006 . The invasion of Pteridium
aquilinum and the impoverishment of the seed bank in fire prone ar-
eas of BrazilianAtlantic forest [ J ] . Biodiv Conser, 15 : 3035—3043
292 云 南 植 物 研 究 30 卷
Roov ers P , Bossuyt B , Igodt B et al. , 2006 . May seed banks contribute
to vegetation restoration on paths in temperate deciduous forest? [ J ] .
Plant Ecol , 187: 25—38
Rosn &er LS, Harrington JT , 2004 . Effect of stratification in polyethylene
glycol solutions on germination of three NorthAmerican shrub species
[ J ] . Seed Sci Technol , 32 : 309—318
Saka ?i A , Sato S, Sakai T et al. , 2005 . A soil seed bank in a mature co-
nifer plantation and establishment of seedlings after clear-cutting in
southwest Japan [ J ] . J apan J For Res, 10 : 295—304
Sala ?ita L , Kar RK , Majee M et al. , 2005 . Identification and character-
ization of mutants capableof rapid seed germination at 10℃ fromacti-
vation-tagged lines of Arabidopsis thaliana [ J ] . J Exp Bot, 56 :
2059—2069
Sand s R , 1981 . Salt resistance in Eucalyptus camaldulensis Dehn . from
three different seed sources [ J ] . Aust For Res, 11 : 93—100
Saut ?u AE, Baskin JM, Baskin CC et al. , 2007 . Classification and eco-
logical relationships of seed dormancy in a seasonal moist tropical for-
est, Panama, Central America [ J ] . Seed Sci Res, 17 : 127—140
Scha ?fer DE , ChilcoteDO, 1969 . Factors influencing persistence and de-
pletion in buried seed populations . I . A model for analysis of param-
eters of buried seed persistence and depletion [ J ] . Crop Sci , 9 :
417—419
Scha ?fer DE , ChilcoteDO, 1970 . Factors influencing persistence and de-
pletion in buried seed populations . II . The effects of soil temperature
and moisture [ J ] . Crop Sci , 10 : 342—345
Sche ?ibe J , Lang A , 1965 . Lettuce seed germination: Evidence for a re-
versible light- induced increase in growth potential and for phyto-
chrome mediation of the low temperature effect [ J ] . Plant Physiol ,
40 : 485—492
Senb eta F , Teketay D, 2002 . Soil seed banks in plantationsand adjacent
natural dry Afromontane forest of central and southern Ethiopia [ J ] .
Trop Ecol , 43 : 229—242
Seri ?o-Silva JC, Rico-Gray V , 2002 . Interacting effects of forest fragment-
ation and howler monkey foraging on germination and dispersal of fig
seeds [ J ] . Oryx, 36 : 266—271
Shen 7YX , J iang J , Chen SG et al. , 2004 . Storage and composition of soil
seed banks of different degraded karst vegetation types in south-east-
ern Yunnan [ J ] . Acta Phytoecol Sin, 28 : 101—106 ( in Chinese
with English abstract and captions to tables and figures)
Shif ?eraw H , Teketay D, Nemomissa S et al. , 2004 . Some biological
characteristics that foster the invasion of Prosopis juliflora ( Sw .) DC .
at MiddleAwash Rift Valley Area, north-eastern Ethiopia [ J ] . J Arid
Environ, 58 : 135—154
Shim &ono A , Washitani I , 2004 . Seedling emergencepatterns and dorman-
cy?germination physiology of Primula modesta in a subalpine region
[ J ] . Ecol Res, 19 : 541—551
Smit RL , Rethman NFG, 1996 . Influence of ruminant digestion on the
germination of Leucaena leucocephala [ J ] . Appl Plant Sci , 10 :
65—66
Stev ?ens JC , Merritt DJ , Flematti GR et al. , 2007 . Seed germination of
agricultural weeds is promoted by the butenolide 3-methyl-2 H-furo
[2 , 3- c ] pyran-2-one under laboratory and field conditions [ J ] .
Plant Soil , 298: 113—124
Stok ?es WE , Hull FH , 1930 . Peanut breeding [ J ] . Agron J , 22 :
1004—1019
Takh ?tajan AL , 1980 . Outline of the classification of flowering plants
(Magnoliophyta) [ J ] . Bot Rev, 46 : 225—359
Takh ?tajan AL , 1986 . Vysshie taksony tsvetkovykh rastenii , isklyuchaya
tsvetkovye ( Higher taxaof vascular plants, except for Phanerogams)
[A ] . In: Takhtajan AL ed ., Problemy paleobotaniki ( Problems of
Paleobotany) [M ] . Nauka, Leningrad, 135—142
Takhtajan AL , 1987 . Sistemamagnoliofitov . ( System of Magnoliophytes)
Nauka, Leningrad
Tayl ?or GB , 1981 . Effect of constant temperature treatments followed by
fluctuating temperatures on the softening of hard seeds of Trifolium
subterraneum L . [ J ] . Aust J Plant Physiol , 8 : 547—558
Tayl ?or GB, 2005 . Hardseededness in Mediterranean annual pasture le-
gumes in Australia: A review [ J ] . Aust J Agric Res, 56 : 645—661
Tayl ?or GB, Revell CK , 1999 . Effect of pod burial , light, and tempera-
ture on seed softening in yellowserradella [ J ] . Aust J Agric Res, 50 :
1203—1209
Tayl ?orson RB , 1970 . Changes in dormancy and viability of weed seeds in
soils [ J ] . Weed Sci , 18 : 265—269
Teke ?tay D, 1998 . The roleof light and temperature in the germination of
twenty herbaceous species from the highlands of Ethiopia [ J ] . Flo-
ra, 193: 411—423
Tele ?wski FW, Zeevaart JAD, 2002 . The 120-yr period for Dr . Beal′s
seed viability experiment [ J ] . Amer J Bot, 89 : 1285—1288
Than ?os CA , Georghiou K , 1988 . Ecophysiology of fire-stimulated seed
germination in Cistus incanus ssp . creticus ( L .) Heywood and
C . salvifolius L . [ J ] . Plant Cell Environ, 11 : 841—849
Thom ?psonK , Grime JP, 1979 . Seasonal variation in the seed banks of
herbaceous species in ten contrasting habitats [ J ] . J Ecol , 67 :
893—921
Thompson K , BandSR, Hodgson JG, 1993 . Seed size and shape predict
persistence in soil [ J ] . Funct Ecol , 7 : 236—241
Thom ?pson K , Ceriani RM, Bakker JP et al. , 2003 . Are seed dormancy
and persistence in soil related ? [ J ] . Seed Sci Res, 13 : 97—100
Thur ?ston JM, 1951 . A comparison of thegrowths of wild and of cultivated
oats in manganese-deficient soils [ J ] . Ann Appl Biol , 38 : 289—302
Tiga ?bu M, Oden PC , 2001 . Effect of scarification, gibberellic acid and
temperatureon seed germination of two multipurpose Albizia species
from Ethiopia [ J ] . Seed Sci Technol , 29 : 11—20
Toor ?op PE , van Aelst A , Hilhorst HWM, 2000 . The second step of the
biphasic endospermcapweakening thatmediatestomato ( Lycopersicon
esculentum) seed germination is under control of ABA [ J ] . J Exp
Bot, 51 : 1371—1379
Trav ?eset A, Verdu M , 2002 . A meta-analysis of the effect of gut treat-
ment on seed germination [ A ] . In: Levey DJ , SilvaWR , Galetti M
eds ., Seed dispersal and frugivory: Ecology, Evolution and Conser-
vation [ M ] . CABI International , Wallingford, Oxon, UK , 339—
350
Twed ?dle JC, Dickie J B, Baskin CC et al., 2003 . Ecological aspects of
seed desiccation sensitivity [ J ] . J Ecol , 91 : 294—304
3923 期 BASKIN and BASKIN: Advances in Understanding Seed Dormancy at theWhole-seedLevel : An . . .
Van %Assche JA, Debucquoy KLA , Rommens WAF , 2003 . Seasonal cy-
cles in the germination capacity of buried seeds of some Leguminosae
( Fabaceae) [ J ] . New Phytol , 158: 315—323
Vena +ble DL , Lawlor L , 1980 . Delayed germination and dispersal in
desert annuals: Escape in space and time [ J ] . Oecologia, 46 :
272—282
Verd #u M, Montilla AI , Pannell JR , 2004 . Paternal effects on functional
gender account for cryptic dioecy in a perennial plant [ J ] . Proc R
Soc Lond B, 271: 2017—2023
Vlee ?shouwers LM , Bouwmeester HJ , 2001 . A simulation model for sea-
sonal changes in dormancy and germination of weed seeds [ J ] . Seed
Sci Res, 11 : 77—92
Vlee ?shouwers LM, Bouwmeester HJ , Karssen CM, 1995 . Redefining
seed dormancy: An attempt to integrate physiology and ecology [ J ] .
J Ecol , 83 : 1031—1037
Voes enek LACJ , Blom CWPM , 1992 . Germination and emergence of
Rumex in river flood-plains . I . Timing of germination and seedbank
characteristics [ J ] . Acta Bot Neerl , 41 : 319—329
Walc +k JL , Baskin CC , Baskin JM, 1999 . Seeds of Thalictrum mirabile
( Ranunculaceae) require cold stratification for lossof nondeep simple
morphophysiological dormancy [ J ] . Can J Bot, 77 : 1769—1776
Walc +k JL , Baskin JM, Baskin CC et al. , 2005 . Defining transient and
persistent seed banks in species with pronounced seasonal dormancy
and germination patterns [ J ] . Seed Sci Res, 15 : 189—196
Walt ?er H , 1979 . Vegetation of the earth and ecological systems of the
geo-biosphere . 2nd ed . Translated from the third, revised German
edition by Joy Wieser . Springer-Verlag, Berlin
Wang QR , Bai Y , Tanino K , 2006 . Seedling emergenceof winterfat ( Kra-
scheninnikovia lanata ( Pursh) A . D . J . Meeuse & Smit) in the
field and its prediction using the hydrothermal time model [ J ] . J
Arid Environ, 64 : 37—53
Went ?FW, 1949 . Ecology of desert plants . II . The effect of rain and tem-
perature on germination and growth [ J ] . Ecology, 30 : 1—13
Wesc ?he W, Pietsch M , Ronnenberg K et al. , 2006 . Germination of fresh
and frost-treated seeds from dry central Asian steppes [ J ] . Seed Sci
Res, 16 : 123—136
Wesl ?ey-Smith J , Walters C , Berjak P et al. , 2004 . The influenceof wa-
ter content, cooling andwarmingrateupon survival of embryonic axes
of Poncirus trifoliata (L .) [ J ] . Cryo Letters, 25 : 129—138
Whit ?tington WJ , Hillman J , Gatenby SM et al. , 1970 . Light and temper-
ature effects on the germination of wild oats [ J ] . Heredity, 25 :
641—650
Wilc ?ox JR , 1968 . Sweetgum seed stratification requirements related to
winter climate at seed source [ J ] . For Sci, 14 : 16—19
Wils ?on TB , Witkowski ETK , 2003 . Seed banks, bark thickness and
change in age and size structure ( 1978 - 1999) of theAfrican savanna
tree, Burkea africana [ J ] . Plant Ecol , 167: 151—162
Wulf ?f RD, Bazzaz FA , 1992 . Effect of the parental nutrient regime on
growth of theprogeny in Abutilon theophrasti (Malvaceae) [ J ] . Am-
er J Bot, 79 : 1102—1107
Xian ?gQY , Zhang WH , Ricklefs RE et al. , 2004 . Regional differences
in rates of plant speciation and molecular evolution: A comparison
between eastern Asia and eastern North America [ J ] . Evolution,
58 : 2175—2184
Yaki ?mowski SB, Hager HA, Eckert CG, 2005 . Limits and effects of inva-
sion by the nonindigenous wetland plant Lythrum salicaria ( purple
loosestrife) : A seed bank analysis [ J ] . Biol Invasions, 7 : 687—698
Youn ?gberg CT, 1952 . Effect of soil fertility on the physical and chemical
properties of tree seed [ J ] . J For, 50 : 850—852
Zami ?th LR , Scarano FR , 2004 . Producao demudas de especies da Rest-
ingas do Municipio do Rio de J aneiro, RJ , Brasil [ J ] . Acta Bot
Brasil , 18 : 161—176
492 云 南 植 物 研 究 30 卷