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Rincker (1981) that classiﬁed Bromus inermis (Poaceae)
as having poor keeping quality, while Medicago sativa Longevity of seedbank-stored seeds 15 Table 4. Correlations among seed longevity values measured in different survey studies. Longevity values for each survey are
given in Table 3. Correlation coefﬁcients (r 2) are given for each linear regression, with the number of species in the analysis given
Priestley et al. (1985)
Ellis Viability Equations
Roos and Davidson (1992) Stanwood
et al. (1985) Ellis Viability
Equations Roos and Davidson
(1992) Toole and
Brown (1946) 0.331 (38) 0.121 (61)
0.211 (28) 0.122 (25)
0.591 (16) 0.491 (14)
0.47 (6) 0.03 (22)
, 0.01 (13)
Not applicable (2) NPGS, USDA National Plant Germplasm System.
Indicates a signiﬁcant trend at P , 0.03.
Indicates a signiﬁcant trend at P , 0.10.
1 (Fabaceae) and Trifolium repens (Fabaceae) had relatively
good keeping quality. The reason for differences in
relative longevity are unclear, although there is likely
to be a genetic basis. The case with Gossypium species
(Malvaceae) may be particularly interesting, in that
species within genome D have wide-ranging longevities, while those with other genome types appear to
store consistently well (Table 1). In addition to
Gossypium, congeners within Allium, Brassica, Bromus,
Datura, Elymus, Lespedeza, Lolium, Phleum, Solanum and
Trifolium showed wide-ranging P50 values. Congeners
of Agropyron, Capsicum, Cucumis, Cucurbita, Festuca,
Hibiscus, Lactuca and Physalis all gave comparable
The distribution of P50s within plant families also
followed some patterns (Fig. 3). Species of Apiaceae
consistently had seeds with P50s less than the median
value of 54 years. Species in Brassicaceae tended to
have either short or long shelf lives, with no species
with medium longevities. Most species in Chenopodiaceae, Cucurbitaceae and Malvaceae had P50s greater than the median value. Wild species within the Chenopodiaceae and Malvaceae also produce seeds with
exceptional persistence in the soil (Toole and Brown,
1946; Telewski and Zeevaart, 2002). Large families
such as the Asteraceae, Fabaceae, Poaceae and Solanaceae
contained species with wide-ranging P50 values
(Fig. 3), and this was also observed in the soil seed
bank (Toole and Brown, 1946; Hendry et al., 1994;
Telewski and Zeevaart, 2002).
Differences in geographic origin may contribute to
variation among P50s within genera and families.
Geographic origins of species in the NPGS collection
were assigned according to Vavilov (1992), Hortus
third (LHB Hortorium, 1976) or the NPGS taxonomic
html/tax_search.pl). The range and median P50s for
each region are given in Fig. 4. Despite the wide range
of P50 values for all geographic areas, there appeared
to be some areas that supported long-lived species
with median P50s $ 80 years (South Asia and
Australia), and some where shelf life tended to b...
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This note was uploaded on 03/03/2013 for the course SFSF 202 taught by Professor Sf during the Spring '13 term at Cambridge.
- Spring '13