Methods in molecular biology (Clifton, N.J.), 2007
The cryopreservation of desiccation-tolerant seeds depends on two key steps: specimen dehydration... more The cryopreservation of desiccation-tolerant seeds depends on two key steps: specimen dehydration in an environment that ensures the attainment of water contents below the high-moisture freezing limit; and transfer and maintenance at a subzero temperature that may be optimized in relation to the seed-lot moisture content and species. Temperatures about 70 degrees C below the glass transition temperature (Tg-70) or lower are recommended for seed storage. For fully desiccation-tolerant (type I) seeds, cryopreservation success tends to be independent of cooling regime and subzero (degrees C) temperature treatment when the seeds are dry. However, to maximize recovery of partially desiccation-tolerant (type II) seeds there can be a requirement for slow cooling, avoidance of storage at certain subzero temperatures, and controlled imbibition following cryopreservation, particularly for endospermic seeds that are high in lipid.
The importance of thermal thresholds for predicting seed dormancy release and germination timing ... more The importance of thermal thresholds for predicting seed dormancy release and germination timing under the present climate conditions and simulated climate change scenarios was investigated. In particular, Vitis vinifera subsp. sylvestris was investigated in four Sardinian populations over the full altitudinal range of the species (from approx. 100 to 800 m a.s.l). Dried and fresh seeds from each population were incubated in the light at a range of temperatures (10-25 and 25/10 °C), without any pre-treatment and after a warm (3 months at 25 °C) or a cold (3 months at 5 °C) stratification. A thermal time approach was then applied to the germination results for dried seeds and the seed responses were modelled according to the present climate conditions and two simulated scenarios of the Intergovernmental Panel on Climate Change (IPCC): B1 (+1·8 °C) and A2 (+3·4 °C). Cold stratification released physiological dormancy, while very few seeds germinated without treatments or after warm st...
Page 1. Seed mass variation potentially masks a single critical water content in recalcitrant see... more Page 1. Seed mass variation potentially masks a single critical water content in recalcitrant seeds Matthew I. Daws1*, Christiane S. Gaméné2, Sheila M. Glidewell3 and Hugh W. Pritchard1 1Seed Conservation Department, Royal ...
Methods in molecular biology (Clifton, N.J.), 2007
The cryopreservation of desiccation-tolerant seeds depends on two key steps: specimen dehydration... more The cryopreservation of desiccation-tolerant seeds depends on two key steps: specimen dehydration in an environment that ensures the attainment of water contents below the high-moisture freezing limit; and transfer and maintenance at a subzero temperature that may be optimized in relation to the seed-lot moisture content and species. Temperatures about 70 degrees C below the glass transition temperature (Tg-70) or lower are recommended for seed storage. For fully desiccation-tolerant (type I) seeds, cryopreservation success tends to be independent of cooling regime and subzero (degrees C) temperature treatment when the seeds are dry. However, to maximize recovery of partially desiccation-tolerant (type II) seeds there can be a requirement for slow cooling, avoidance of storage at certain subzero temperatures, and controlled imbibition following cryopreservation, particularly for endospermic seeds that are high in lipid.
The importance of thermal thresholds for predicting seed dormancy release and germination timing ... more The importance of thermal thresholds for predicting seed dormancy release and germination timing under the present climate conditions and simulated climate change scenarios was investigated. In particular, Vitis vinifera subsp. sylvestris was investigated in four Sardinian populations over the full altitudinal range of the species (from approx. 100 to 800 m a.s.l). Dried and fresh seeds from each population were incubated in the light at a range of temperatures (10-25 and 25/10 °C), without any pre-treatment and after a warm (3 months at 25 °C) or a cold (3 months at 5 °C) stratification. A thermal time approach was then applied to the germination results for dried seeds and the seed responses were modelled according to the present climate conditions and two simulated scenarios of the Intergovernmental Panel on Climate Change (IPCC): B1 (+1·8 °C) and A2 (+3·4 °C). Cold stratification released physiological dormancy, while very few seeds germinated without treatments or after warm st...
Page 1. Seed mass variation potentially masks a single critical water content in recalcitrant see... more Page 1. Seed mass variation potentially masks a single critical water content in recalcitrant seeds Matthew I. Daws1*, Christiane S. Gaméné2, Sheila M. Glidewell3 and Hugh W. Pritchard1 1Seed Conservation Department, Royal ...
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