Variation in seed dormancy among mother plants, populations and years of seed collection

Abstract

Variation in dormancy level was tested in seeds of four species, each collected from three populations in 1994 and 1995 (experiment 1) Germination was tested in light and darkness on recently-harvested seeds and on those after-ripened in dry storage for one year In addition, seeds from each of eight individual plants within each of eight populations were tested for germination when recently harvested and after warm stratification or cold stratification followed by a drying period (experiment 2) Seeds from the two years differed in dormancy level in Silene noctiflora, Sinapis arvensis and Spergula arvensis Germination percentage differed significantly among populations in Sinapis arvensis and Spergula arvensis in both experiments and in Thlaspi arvense in experiment 2 Furthermore, dormancy level in seeds from different mother plants also varied in the three species tested in experiment 2 Variations at the three levels tested (year, population and mother plant) indicate that these species have a random pattern of variation in dormancy level It is concluded that variation in seed dormancy among mother plants, populations and years must be taken into account when testing the germination characteristics of a species and also when attempting to model weed seed bank dynamics

Environmental and Genetic Sources of Diversification in the Timing of Seed Germination: Implications for the Evolution of Bet Hedging

“…Variance in time to germination and hatching asynchrony have mostly been discussed in the context of among-season delays, or dormancy (Cohen 1966;Silvertown 1984;Philippi 1993;Nilsson et al 1994;Evans and Cabin 1995;Andersson and Milberg 1998;Clauss and Venable 2000;Easterling and Ellner 2000), but considerable asynchrony within a season also exists (e.g., Kalisz 1986;Biere 1991a;Clauss and Venable 2000;Simons and Johnston 2000a;Galloway 2002). Because the timing of germination is closely associated with fitness, explaining variance in this trait is of broad evolutionary interest.…”

Enhancement of seed germination in stored seeds using different pre-sowing treatments in Bauhinia purpurea L.

“…However, in the present study, seed storage affects the seed germination up to 50 per cent and it could be due to influence of seed source on dormancy pattern. Andersson and Milberg (1998) and Meyer and Pendleton (2000) recorded that the intensity of dormancy in a given species exhibits high degrees of variation at several levels such as among populations, within populations and between two fruiting seasons even between seeds collected in different years from *Analysis and separation was made using arc sine transformation for germination (%) Prasad and Nautiyal (1996) and Lopes et al (2007) reported improvement in seed germination of Bauhinia species through the mechanical scarification and sulphuric acid treatments. It is also reported that seed germination of B. purpurea is affected by temperature 25 to 30°C (Reino et al, 2008).…”

Sowing seeds for the future: the need for establishing protocols for the study of seed dormancy

“…When investigating seed dormancy, researchers should bear in mind the ideas that dormancy is not an all-ornothing trait and that the degree of seed dormancy varies at several scales (Anderssen & Milberg 1998). Intraspecific variation in the level of seed dormancy is common among Brazilian species (Lacerda et al, 2004;Silveira et al 2012), and the question posed is no longer whether a species is dormant or not.…”