Influencing factors to seed dormancy and germination characteristics of Sorbus pohuashanensis were studied. These factors included the morphological development of embryos,the mechanical obstruction of the seed coat,t...Influencing factors to seed dormancy and germination characteristics of Sorbus pohuashanensis were studied. These factors included the morphological development of embryos,the mechanical obstruction of the seed coat,the water and air permeability of seed coat,and the biologic inhibition of extracts from different parts of seed. The results showed that when the seeds of Sorbus pohuashanensis became mature,the morphological development of the embryos was complete. The influencing effect of the mechanical obstruction,the water and permeability of seed coat for seed germination was little; there were inhibited substances to the seed of cabbage germination in seed coat and embryo,the germination depressor could be fat soluble substances. This indicated that the dormant degree was different for the different embryo parts. Cotyledon and hypocotyl was in low degree dormancy,whereas radicle and epicotyl was in high degree dormancy. To some extent,the germination rate of in vitro cultured embryos was increased with detruncating cotyledon and radicle treament. A 1∶3 mixture of seeds and sharp sand at low temperature in favor of removing dormancy. Treated by 200 mg·L -1 6-BA for 24 h,then remained in low temperature (0～5 ℃),seeds could germinated well (the germination rate could reached 31.56% in 3 month treatment). ABA completely inhibited the germination of seed,warm-cold varied temperature treatment did not promote the removing of dormancy of seed.展开更多
A study was conducted to determine the effects of electrostatic field （ESF） treatment on seed germination and seedling growth of Sorbus pohuashanesis. The experiments were arranged by uniform design computed by the ...A study was conducted to determine the effects of electrostatic field （ESF） treatment on seed germination and seedling growth of Sorbus pohuashanesis. The experiments were arranged by uniform design computed by the Data Processing System （DPS）, including three levels of seeds soaking time, four levels of ESF intensity and four levels of ESF treatment time, with 12 treatments. Ten seeds were used in each treatment with three replicates. Seed vigor, seed germinating ability, emergence rate of seedling, survival rate of seedling, and seedling height and diameter, as well as the change in activities of superoxide dismutase （SOD）, soluble protein contents, total chlorophyll contents, soluble total sugar contents in leaves of S. pohuashanensis seedlings were measured after ESF treatments. The experiment results show that ESF treatment could improve the water absorption ability of dry seeds of S. pohuashanensis, resulting in fast germination at room temperature under light conditions. Combined treatment of ESF with cold stratification could increase seed germination percentage significantly （to 42.20%）, promote seedling height growth, affect leaf SOD activity, and could raise contents of total chlorophyll, soluble protein, and total soluble sugar in leaves. Seed soaking time had a significant effect on seed relative electroconductivity, seed germination under light, SOD activity, soluble protein content and total soluble sugar content of seedling leaves. ESF intensity exerted a moderate effect on these indexes. ESF treatment time only had significant effect on total chlorophyll contents, no evident effect on other indexes.展开更多
We characterized the effects of KNO3 pretreatment and germination temperature on dormancy breaking and germination of mature mountain ash seeds. Seeds treated with KNO3 and germinated at 25 ℃ followed by 5 ℃ had sig...We characterized the effects of KNO3 pretreatment and germination temperature on dormancy breaking and germination of mature mountain ash seeds. Seeds treated with KNO3 and germinated at 25 ℃ followed by 5 ℃ had significantly higher germination percentages and germination potentials （51% and 49%, respectively）, compared with controls. These treated seeds also exhibited reduced germination initiation times （minimum of 48 days）, and elevated germination rate indices （up to 97）. The germination of seeds subjected to long-term cold storage （2 years at 0-5 ℃） was also significantly improved by 3 days of 4% KNO3 pretreatment before germinating under a variable temperature regimen （5 ℃ followed by 25 ℃, and followed by 5 ℃）. Germination percentages and germination potentials for these cold-stored seeds reached 67% and 54%, respectively, and the germination rate index increased to 126.99. Pretreatment of mountain ash seeds with KNO3 represents a practical, effective, and pollution-free method for improving germination, and can be implemented easily within a variety of nursery settings.展开更多
文摘Influencing factors to seed dormancy and germination characteristics of Sorbus pohuashanensis were studied. These factors included the morphological development of embryos,the mechanical obstruction of the seed coat,the water and air permeability of seed coat,and the biologic inhibition of extracts from different parts of seed. The results showed that when the seeds of Sorbus pohuashanensis became mature,the morphological development of the embryos was complete. The influencing effect of the mechanical obstruction,the water and permeability of seed coat for seed germination was little; there were inhibited substances to the seed of cabbage germination in seed coat and embryo,the germination depressor could be fat soluble substances. This indicated that the dormant degree was different for the different embryo parts. Cotyledon and hypocotyl was in low degree dormancy,whereas radicle and epicotyl was in high degree dormancy. To some extent,the germination rate of in vitro cultured embryos was increased with detruncating cotyledon and radicle treament. A 1∶3 mixture of seeds and sharp sand at low temperature in favor of removing dormancy. Treated by 200 mg·L -1 6-BA for 24 h,then remained in low temperature (0～5 ℃),seeds could germinated well (the germination rate could reached 31.56% in 3 month treatment). ABA completely inhibited the germination of seed,warm-cold varied temperature treatment did not promote the removing of dormancy of seed.
基金supported by the Key Technologies R&D Program of China during 2006–2010 (2006BAD03A04)
文摘A study was conducted to determine the effects of electrostatic field （ESF） treatment on seed germination and seedling growth of Sorbus pohuashanesis. The experiments were arranged by uniform design computed by the Data Processing System （DPS）, including three levels of seeds soaking time, four levels of ESF intensity and four levels of ESF treatment time, with 12 treatments. Ten seeds were used in each treatment with three replicates. Seed vigor, seed germinating ability, emergence rate of seedling, survival rate of seedling, and seedling height and diameter, as well as the change in activities of superoxide dismutase （SOD）, soluble protein contents, total chlorophyll contents, soluble total sugar contents in leaves of S. pohuashanensis seedlings were measured after ESF treatments. The experiment results show that ESF treatment could improve the water absorption ability of dry seeds of S. pohuashanensis, resulting in fast germination at room temperature under light conditions. Combined treatment of ESF with cold stratification could increase seed germination percentage significantly （to 42.20%）, promote seedling height growth, affect leaf SOD activity, and could raise contents of total chlorophyll, soluble protein, and total soluble sugar in leaves. Seed soaking time had a significant effect on seed relative electroconductivity, seed germination under light, SOD activity, soluble protein content and total soluble sugar content of seedling leaves. ESF intensity exerted a moderate effect on these indexes. ESF treatment time only had significant effect on total chlorophyll contents, no evident effect on other indexes.
文摘We characterized the effects of KNO3 pretreatment and germination temperature on dormancy breaking and germination of mature mountain ash seeds. Seeds treated with KNO3 and germinated at 25 ℃ followed by 5 ℃ had significantly higher germination percentages and germination potentials （51% and 49%, respectively）, compared with controls. These treated seeds also exhibited reduced germination initiation times （minimum of 48 days）, and elevated germination rate indices （up to 97）. The germination of seeds subjected to long-term cold storage （2 years at 0-5 ℃） was also significantly improved by 3 days of 4% KNO3 pretreatment before germinating under a variable temperature regimen （5 ℃ followed by 25 ℃, and followed by 5 ℃）. Germination percentages and germination potentials for these cold-stored seeds reached 67% and 54%, respectively, and the germination rate index increased to 126.99. Pretreatment of mountain ash seeds with KNO3 represents a practical, effective, and pollution-free method for improving germination, and can be implemented easily within a variety of nursery settings.
