To ascertain the genotypic difference of cadmium tolerance of different varieties of maize, effects of cadmium stress on the germination rate, germination index, vigor index, root length and fresh weight, and shoot le...To ascertain the genotypic difference of cadmium tolerance of different varieties of maize, effects of cadmium stress on the germination rate, germination index, vigor index, root length and fresh weight, and shoot length and fresh weight of seeds of 12 main varieties of maize widely cultivated in central Hunan were studied. The results showed that the cadmium stress had small impact on the germination rate and germination index of maize seeds, but it had obvious effects on the vigor index, root and shoot growth of maize seeds, and the inhibition effects on the roots were more obvious than the shoots. Among the 12 varieties of maize, Qiandan 12, Dushiliren, Nuobatianxia and Nongda 3138 were tolerant to cadmium stress, while Tianguan 218 was sensitive to cadmium stress, and the tolerance of other varieties of maize to cadmium stress was moderate.展开更多
Soil salinity has a major impact on rice seed germination,severely limiting rice production.Herein,a rice germination defective mutant under salt stress(gdss)was identified by using chemical mutagenesis.The GDSS gene ...Soil salinity has a major impact on rice seed germination,severely limiting rice production.Herein,a rice germination defective mutant under salt stress(gdss)was identified by using chemical mutagenesis.The GDSS gene was detected via MutMap and shown to encode potassium transporter OsHAK9.Phenotypic analysis of complementation and mutant lines demonstrated that OsHAK9 was an essential regulator responsible for seed germination under salt stress.OsHAK9 is highly expressed in germinating seed embryos.Ion contents and non-invasive micro-test technology results showed that OsHAK9 restricted K^(+)efflux in salt-exposed germinating seeds for the balance of K^(+)/Na^(+).Disruption of OsHAK9 significantly reduced gibberellin 4(GA4)levels,and the germination defective phenotype of oshak9a was partly rescued by exogenous GA_(3)treatment under salt stress.RNA sequencing(RNA-seq)and real-time quantitative polymerase chain reaction analysis demonstrated that the disruption of OsHAK9 improved the GA-deactivated gene OsGA2ox7 expression in germinating seeds under salt stress,and the expression of OsGA2ox7 was significantly inhibited by salt stress.Null mutants of OsGA2ox7 created using clustered,regularly interspaced,short palindromic repeat(CRISPR)/CRISPR-associated nuclease 9 approach displayed a dramatically increased seed germination ability under salt stress.Overall,our results highlight that OsHAK9 regulates seed germination performance under salt stress involving preventing GA degradation by mediating OsGA2ox7,which provides a novel clue about the relationship between GA and OsHAKs in rice.展开更多
Shrubby seablite or lani(Suaeda fruticosa Forssk)is a perennial euhalophyte with succulent leaves,which could be planted on arid-saline lands for restoration and cultivated as a non-conventional edible or cash crop.Kn...Shrubby seablite or lani(Suaeda fruticosa Forssk)is a perennial euhalophyte with succulent leaves,which could be planted on arid-saline lands for restoration and cultivated as a non-conventional edible or cash crop.Knowledge about the impacts of maternal saline environment on seed attributes of this important euhalophyte is lacking.This study investigated the effects of maternal salinity on yield,size and stress tolerance of S.fruticosa seeds.Seedlings of S.fruticosa were grown in a green net house under increasing maternal salinity levels(0,300,600 and 900 mM NaCl)until seed production.Total yield,size,stress tolerance and germination of the descended seeds under different maternal saline conditions were examined.Plants grown under saline conditions(300,600 and 900 mM NaCl)produce a substantially higher quantity of seeds than plants grown under non-saline condition(0 mM NaCl).Low maternal salinity(300 mM NaCl)improves seed size.Seeds produced under all maternal salinity levels display a higher tolerance to low temperature(night/day thermoperiod of 10℃/20℃),whereas seeds produced under 300 mM NaCl maternal saline condition show a better tolerance to high temperature(night/day thermoperiod of 25℃/35℃)during germination.Seeds from all maternal saline conditions germinate better in the 12 h photoperiod(12 h light/12 h dark)than in the dark(24 h dark);however,seeds produced from low and moderate maternal saline conditions(300 and 600 mM NaCl)show a higher germination in the dark than those from control and high maternal saline conditions(0 and 900 mM NaCl).In general,maternal salinity is found to improve yield,size and stress tolerance of S.fruticosa seeds.展开更多
Ex situ conservation in seed banks is a potential complementary conservation strategy for native plant species.It is well established that ex situ seed banking of native wild plants prolongs seed viability and thereby...Ex situ conservation in seed banks is a potential complementary conservation strategy for native plant species.It is well established that ex situ seed banking of native wild plants prolongs seed viability and thereby preserves genetic and species diversity for future use.We evaluated ex situ storage potential of eight halophytic species from deserts in the United Arab Emirates(UAE)by studying seed germination.Specifically,we examined the germinability of freshly collected seeds and seeds stored for three years in a seed bank.We also examined the effect of light conditions on fresh and stored seed germination.Fresh seeds of seven of the eight species tested had a higher germination rates under 12/12 h light/dark fluctuations than did those exposed to total darkness.Storage reduced light sensitivity in Halocnemum strobilaceum,Suaeda aegyptiaca,Salsola drummondii and Salsola imbricata,but increased the requirement for light in Arthrocnemum macrostachyum.In Anabasis setifera,storage decreased germination percentage when there was a 12-hour light/dark fluctuation,but increased germination rate when exposed to the dark treatment.Storage significantly reduced germination in both the light/dark and dark treatments in Suaeda vermiculata and S.aegyptiaca.Germination speed also responded differently to storage;whereas Timson's index significantly increased in A.macrostachyum and H.strobilaceum,it significantly decreased for S.drummondii,S.aegyptiaca and S.vermiculata.Germination of these species at a range of temperatures requires further testing;additionally,we strongly suggest that these laboratory findings be complemented by field studies.展开更多
基金Supported by Key Laboratory of Pesticide Harmless Application of an University in Hunan Province
文摘To ascertain the genotypic difference of cadmium tolerance of different varieties of maize, effects of cadmium stress on the germination rate, germination index, vigor index, root length and fresh weight, and shoot length and fresh weight of seeds of 12 main varieties of maize widely cultivated in central Hunan were studied. The results showed that the cadmium stress had small impact on the germination rate and germination index of maize seeds, but it had obvious effects on the vigor index, root and shoot growth of maize seeds, and the inhibition effects on the roots were more obvious than the shoots. Among the 12 varieties of maize, Qiandan 12, Dushiliren, Nuobatianxia and Nongda 3138 were tolerant to cadmium stress, while Tianguan 218 was sensitive to cadmium stress, and the tolerance of other varieties of maize to cadmium stress was moderate.
基金supported by the National Natural Science Foundation of China(Grant Nos.32272169,32000377,32172037,and 31601387)the Natural Science Foundation of Guangdong Province(Grant No.2022A1515110449)the Hainan Yazhou Bay Seed Laboratory(project of B21HJ1002)。
文摘Soil salinity has a major impact on rice seed germination,severely limiting rice production.Herein,a rice germination defective mutant under salt stress(gdss)was identified by using chemical mutagenesis.The GDSS gene was detected via MutMap and shown to encode potassium transporter OsHAK9.Phenotypic analysis of complementation and mutant lines demonstrated that OsHAK9 was an essential regulator responsible for seed germination under salt stress.OsHAK9 is highly expressed in germinating seed embryos.Ion contents and non-invasive micro-test technology results showed that OsHAK9 restricted K^(+)efflux in salt-exposed germinating seeds for the balance of K^(+)/Na^(+).Disruption of OsHAK9 significantly reduced gibberellin 4(GA4)levels,and the germination defective phenotype of oshak9a was partly rescued by exogenous GA_(3)treatment under salt stress.RNA sequencing(RNA-seq)and real-time quantitative polymerase chain reaction analysis demonstrated that the disruption of OsHAK9 improved the GA-deactivated gene OsGA2ox7 expression in germinating seeds under salt stress,and the expression of OsGA2ox7 was significantly inhibited by salt stress.Null mutants of OsGA2ox7 created using clustered,regularly interspaced,short palindromic repeat(CRISPR)/CRISPR-associated nuclease 9 approach displayed a dramatically increased seed germination ability under salt stress.Overall,our results highlight that OsHAK9 regulates seed germination performance under salt stress involving preventing GA degradation by mediating OsGA2ox7,which provides a novel clue about the relationship between GA and OsHAKs in rice.
基金The authors would like to thank the Higher Education Commission of Pakistan for the provision of funds.
文摘Shrubby seablite or lani(Suaeda fruticosa Forssk)is a perennial euhalophyte with succulent leaves,which could be planted on arid-saline lands for restoration and cultivated as a non-conventional edible or cash crop.Knowledge about the impacts of maternal saline environment on seed attributes of this important euhalophyte is lacking.This study investigated the effects of maternal salinity on yield,size and stress tolerance of S.fruticosa seeds.Seedlings of S.fruticosa were grown in a green net house under increasing maternal salinity levels(0,300,600 and 900 mM NaCl)until seed production.Total yield,size,stress tolerance and germination of the descended seeds under different maternal saline conditions were examined.Plants grown under saline conditions(300,600 and 900 mM NaCl)produce a substantially higher quantity of seeds than plants grown under non-saline condition(0 mM NaCl).Low maternal salinity(300 mM NaCl)improves seed size.Seeds produced under all maternal salinity levels display a higher tolerance to low temperature(night/day thermoperiod of 10℃/20℃),whereas seeds produced under 300 mM NaCl maternal saline condition show a better tolerance to high temperature(night/day thermoperiod of 25℃/35℃)during germination.Seeds from all maternal saline conditions germinate better in the 12 h photoperiod(12 h light/12 h dark)than in the dark(24 h dark);however,seeds produced from low and moderate maternal saline conditions(300 and 600 mM NaCl)show a higher germination in the dark than those from control and high maternal saline conditions(0 and 900 mM NaCl).In general,maternal salinity is found to improve yield,size and stress tolerance of S.fruticosa seeds.
文摘Ex situ conservation in seed banks is a potential complementary conservation strategy for native plant species.It is well established that ex situ seed banking of native wild plants prolongs seed viability and thereby preserves genetic and species diversity for future use.We evaluated ex situ storage potential of eight halophytic species from deserts in the United Arab Emirates(UAE)by studying seed germination.Specifically,we examined the germinability of freshly collected seeds and seeds stored for three years in a seed bank.We also examined the effect of light conditions on fresh and stored seed germination.Fresh seeds of seven of the eight species tested had a higher germination rates under 12/12 h light/dark fluctuations than did those exposed to total darkness.Storage reduced light sensitivity in Halocnemum strobilaceum,Suaeda aegyptiaca,Salsola drummondii and Salsola imbricata,but increased the requirement for light in Arthrocnemum macrostachyum.In Anabasis setifera,storage decreased germination percentage when there was a 12-hour light/dark fluctuation,but increased germination rate when exposed to the dark treatment.Storage significantly reduced germination in both the light/dark and dark treatments in Suaeda vermiculata and S.aegyptiaca.Germination speed also responded differently to storage;whereas Timson's index significantly increased in A.macrostachyum and H.strobilaceum,it significantly decreased for S.drummondii,S.aegyptiaca and S.vermiculata.Germination of these species at a range of temperatures requires further testing;additionally,we strongly suggest that these laboratory findings be complemented by field studies.
