Effect of soil moisture during stratification on dormancy release in seeds of five common weed species

Abstract

Summary Although the effects of cold stratification on the release of physiological dormancy in seeds have been studied extensively, knowledge of the role of soil moisture content on seed dormancy release during cold stratification is limited. Our study determined seed dormancy characteristics and the effect of soil moisture content on seed dormancy breakage during cold stratification in the five common weed species Amaranthus retroflexus, Chenopodium album, Chenopodium hybridum, Plantago lanceolata and Setaria glauca. Seeds of all five species were dormant at the time of harvest and their germination response to light and temperature varied. Soil moisture content had a significant effect on seed dormancy release of all species except P. lanceolata. Germination percentage of A. retroflexus, C. album, C. hybridum increased and then decreased as soil moisture content increased, regardless of germination test temperature. The optimal soil moisture content and seed moisture content for dormancy breakage of A. retroflexus, C. album, C. hybridum were 8%, 12%, 8% and 22.0%, 37.7%, 25.7% respectively. Dry storage (after‐ripening) significantly increased germination of S. glauca. Moreover, increasing soil moisture content first slowed and then increased dormancy breakage in S. glauca. These results suggest that data on soil moisture content should be incorporated into models that predict weed seed dormancy breakage and timing of seedling emergence as well as those for weed management.

Seed dormancy release of Halenia elliptica in response to stratification temperature, duration and soil moisture content

“…It is clear from our results that soil moisture content plays a pivotal role in seed dormancy release during cold stratification in seeds of all six populations. Consistent with previous studies [ 13 – 15 ], soil moisture content must reach a critical level for seed dormancy release to occur during cold stratification. In our study, at cold stratification temperatures of 2 °C and 5 °C, seed germination of all six populations begins to occur when soil moisture content was 4% or more.…”

“…Germination percentage of seeds of Alnus glutinosa and Betula pubescens decreased with increased seed moisture content [14]. On the contrary, seed germination of Amaranthus retroflexus, Chenopodium album and C. hybridum increased first and then decreased as the soil moisture content was increased during cold stratification [15].…”

“…Some studies have determined the response of seed dormancy release to single environmental factors such as temperature [5,7,[16][17][18], winter duration [11,19] and seed/soil moisture content [13][14][15] during cold stratification. The results of these studies suggested that global warming could impact the dynamics of seed dormancy release and thus delay or enhance plant regeneration from seeds [20][21][22][23].…”

“…Further, temperature, duration and soil moisture content requirements for dormancy release vary among species, and this variation may be an adaptation strategy of species to their specific habitats [15]. Further, species that occur over a wide geographical range may exhibit local adaptations in their specific requirements for dormancy release.…”

“…In addition to temperature and duration of cold stratification, soil moisture content is another key environmental factor affecting seed dormancy release. Previous studies [ 13 – 15 ] have reported that seed dormancy release during cold stratification varies with soil moisture content. Germination percentage of seeds of Alnus glutinosa and Betula pubescens decreased with increased seed moisture content [ 14 ].…”