Fluctuations of levels of several endogenous plant hormones in isolated rice ( Oryza sativa ssp. japonica) embryos during early and mid-embryogenesis and early stages of germination were studied by enzyme-linked immun...Fluctuations of levels of several endogenous plant hormones in isolated rice ( Oryza sativa ssp. japonica) embryos during early and mid-embryogenesis and early stages of germination were studied by enzyme-linked immunosorbent assay (ELISA). Embryos were collected at different days after pollination (DAP) and different days after imbibition (DAI) of mature seeds. The contents of gibberellin(1) (GA(1)), abscisic acid (ABA), isopentenyladenine and isopentenyladenosine ( iPAs), zeatin and zeatin riboside ( ZRs) were immunochemically assayed. The GA(1) level was the highest among all hormones tested. The variations of GA(1) levels were opposite with the ABA levels, with some exceptions. During early and mid-embryogenesis, the levels of GA(1) and ABA were the highest at 4 DAP. From 8 to 18 DAP, GA(1) level declined, whereas the ABA level increased. During germination, GA(1) level increased at 2 DAI whereas simultaneously the ABA content decreased. The highest ratio of GA(1)/ABA was observed at 2 DAI The levels of iPAs and ZRs were maxima in the embryos at 4 DAP, decreased to a very low level and maintained constant thereafter. Our results provide further evidence that GA(1) plays an important role in the early stages of embryo development and germination. The balance between GA(1) and ABA, rather than their absolute contents, controls these processes throughout the development, whereas iPAs and ZRs may play important roles in early embryogenesis. The use of isolated embryos as starting material avoids the usual interferences with other tissues such as the endosperm. In addition, this is the first report dealing with the hormonal balance of early-embryos in rice.展开更多
With Welsh Onion seeds employed as materials, effects of magnetized water on seed Germination were studied. The results showed the treatment of magnetized water soaking for 4 h promoted water absorption rate and amyla...With Welsh Onion seeds employed as materials, effects of magnetized water on seed Germination were studied. The results showed the treatment of magnetized water soaking for 4 h promoted water absorption rate and amylase ac- tivities of seeds significantly, which accelerated the transformation process of en- dosperm starch to soluble sugar, resulting in emergence of 36 hours in advance under low temperature condition. Germination rate and germination potential of magnetized water soaking were higher than the contrast by 6.7% and 10.0%, which helped cultivate vigorous seedling.展开更多
Objective] This study almed to soIve technical probIems in artificial breed-ing of Parashorea chinensis. [Method] The effects of different iI umination intensity and soiI moisture on seed germination rate and emergenc...Objective] This study almed to soIve technical probIems in artificial breed-ing of Parashorea chinensis. [Method] The effects of different iI umination intensity and soiI moisture on seed germination rate and emergence of P. chinensis were in-vestigated. [Result] Under conditions of ill umination intensity of 40% and soiI mois-ture of 60%, the seeds of P. chinensis showed the highest germination rate. [Con-clusion] This study wiI provide some basic information for the ex-situ conservation, repopuIation and deveIopment and utiIization of P. chinensis.展开更多
The research used bioassay method to explore seed tolerance of Cd in terms of seed germination and seedling growth. Specifically, 12 rice varieties of three types were investigated under Cd stress, covering germinatio...The research used bioassay method to explore seed tolerance of Cd in terms of seed germination and seedling growth. Specifically, 12 rice varieties of three types were investigated under Cd stress, covering germination rate, shooting index, vigor index, seedling and shoot lengths, and fresh weights. The results showed that as Cd concentration grew, seed germination and seedling growth kept increasingly inhibited; germination index, vigor index, root length, shoot length and fresh weights went down; inhibition effects on seed germination and seedling growth were conventional rice〉two-line hybrid rice〉three-line hybrid ,rice. Shanyou 9588, Tianyou 998, Chuanxiang 8, and Y Liangyou 1 performed ~rongly in Cd tolerance; C Liangyou 651, Nei 5 You 263, Xiangwanxian 16, Huanghuazhan, Xiangwanxian 13, and Zhunliangyou 527 performed poorly in Cd tolerance, and Cd tolerance of rest treatments were moderate.展开更多
ObjectiveThis study aimed to investigate the characters of major hydrolase isozymes in wheat seeds. MethodThe spectra of amylase, esterase and proteolytic enzyme isozymes in the germ, endosperm and radicle were studie...ObjectiveThis study aimed to investigate the characters of major hydrolase isozymes in wheat seeds. MethodThe spectra of amylase, esterase and proteolytic enzyme isozymes in the germ, endosperm and radicle were studied in detail during the germination process using the polyacrylamide gel electrophoresis(PAGE). ResultThe results indicated that isozymes of amylase and esterase changed obviously in the endosperm during the germination, while isozymes of proteolytic enzyme exhibited distinct variation in the germ and radicle. ConclusionThis study provides basic data for effeciently improving the germination rate of crop seeds in the future.展开更多
Peltophorum dubium seeds provided by Anhembi, SP were scarified in 98% H2SO4 for 15 min to overcome mechani-cal dormancy. Seeds were primed in solutions of 0.2% Captan at 10 C and 27C, PEG 6000 -1.0 MPa at 10C and 27...Peltophorum dubium seeds provided by Anhembi, SP were scarified in 98% H2SO4 for 15 min to overcome mechani-cal dormancy. Seeds were primed in solutions of 0.2% Captan at 10 C and 27C, PEG 6000 -1.0 MPa at 10C and 27C, 0.5 mol KNO3, 0.75 Mol KNO3, 1.0 Mol KNO3. Eight treatments including the primed seeds and nonprimed seeds, five replicates with 100 seeds for each treatment, were set to 15-cm-Petri dish with double filter paper moistened with testing solution PEG in refrigerator at 27C. For the experiments of all the groups, osmotic potential were 0.0, -0.2, -0.4, -0.6, -0.8, -1.0, -1.2, and -1.4 MPa. P. dubium seeds were also set to water stress experiment in rolled paper with PEG solutions from 0.0 to -1.0 M Pa. Germination percentage decreased with the increase of PEG concentration. Control group had a better germination percentage than other groups. Germination hardly occurred in PEG -1.4 MPa.展开更多
Previous studies have demonstrated the possible role of several aquaporins in seed germination. But systematic investigation of the role ofaquaporin family members in this process is lacking. Here, the developmental r...Previous studies have demonstrated the possible role of several aquaporins in seed germination. But systematic investigation of the role ofaquaporin family members in this process is lacking. Here, the developmental regulation of plasma membrane intrinsic protein (PIP) expression throughout germination and post-germination processes in rice embryos was analyzed. The expression patterns of the PIPs suggest these aquaporins play different roles in seed germination and seedling growth. Partial silencing of the water channel genes, OsPIP1;1 and OsPIP1:3, reduced seed germination while over-expression of OsPIP1:3 promoted seed germination under water-stress conditions. Moreover, spatial expression analysis indicates that OsPIP1:3 is expressed predominantly in embryo during seed germination. Our data also revealed that the nitric oxide (NO) donors, sodium nitroprusside (SNP) and S-nitrosoglutathione (GSNO), promoted seed germination; furthermore, the NO scavenger, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, inhibited germination and reduced the stimulative effects of SNP and GSNO on rice germination. Exogenous NO stimulated the transcription of OsPIP1:1, OsPIP1:2, OsPIP1:3 and OsPIP2:8 in germinating seeds. These results suggest that water channels play an important role in seed germination, acting, at least partly, in response to the NO signaling pathway.展开更多
Seeds germination and seedling stages were studied on the legume seeds of Vicia angustifolia L. to reveal the effects of drought stress on germination char- acteristics and water absorption characteristics. The result...Seeds germination and seedling stages were studied on the legume seeds of Vicia angustifolia L. to reveal the effects of drought stress on germination char- acteristics and water absorption characteristics. The results showed that the rate of seed water uptake,germination percentage,germination index,vigor index,seedling height,root length and plant water content decreased with the increase of concen- tration of PEG stress. However,seedling and root dry weight and root/shoot ratio ini- tially increased followed by a decrease. The lowest osmotic potential threshold was -0.42 MPa.展开更多
Soybean [Glycine max (L.)] is one of the most important protein and oil seed crop. In attention to time consuming and effect of uncontrolled agents like soil elements and hemisphere, study of tolerance in soybean to...Soybean [Glycine max (L.)] is one of the most important protein and oil seed crop. In attention to time consuming and effect of uncontrolled agents like soil elements and hemisphere, study of tolerance in soybean to water stress during germination was investigated. Four soybean cultivars 'Williams, Linford, L 17 and M7' were screened for drought tolerance by treatment of PEG6000 concentration for induce osmotic potentials (0, -3, -6, -9 bar). A factorial experiment based on completely randomized design with three replications was conducted. Germination percentage, radicle and hypocotyls length, fresh and dry weight of radicle, hypocotyl and seedling, TWC%, MDG, rate of daily germination and percentage of abnormal seedling were measured. Variance analysis of data indicated that difference between osmotic potential had significant effect on all parameters except germination percentage. A significant reduction in fresh weight of radicle and seedling, percentage of abnormal seedlings was observed for the genotypes as the concentration of PEG increased. In interaction between cultivars and water stress level, Linford and M7 with less damage had the highest yield in fresh and dry weight of radicle, respectively. Drought is one of the most important abiotic limited potential in germination and primary growth on these cultivars.展开更多
[Objective] This study aimed to investigate the effects of phosphine on germination and physiological characteristics of rice seeds. [Method] Simulation envi- ronments were conducted to study the effects of high-level...[Objective] This study aimed to investigate the effects of phosphine on germination and physiological characteristics of rice seeds. [Method] Simulation envi- ronments were conducted to study the effects of high-level phosphine on germination status and physiological characteristics of rice seeds and explore the early environ- mental and ecological effects of phosphine on rice growth in phosphorus cycle of paddy field. [Result] Experimental results showed that the increase of phosphine con- centration in the environment resulted in the decrease of germination rate and ger- mination potential by 11.11% and 19.71%, respectively. In addition, the activities of catalase (CAT) and peroxidase (POD) were reduced to 94.35% and 92.61%, respec- tively; the content of malondialdehyde (MDA) was maximally increased by 29.11%, indicating that both germination potential and growth condition of rice seeds were in- hibited under conditions of high-level phosphine. [Conclusion] This study provided theoretical basis for investigating the effects of phosphine on germination of rice seeds under natural environment.展开更多
The true freshwater crabs(Crustacea,Decapoda,Brachyura) are highly adapted to life in freshwater and complete their life cycle entirely independently of sea water.All true freshwater crabs exhibit direct development a...The true freshwater crabs(Crustacea,Decapoda,Brachyura) are highly adapted to life in freshwater and complete their life cycle entirely independently of sea water.All true freshwater crabs exhibit direct development and lack the free-living larval forms(zoea and megalopa) typical of most other brachyurans.After a prolonged embryonic period(during which they pass through the typical brachyuran larval forms embryologically) the eggs of true freshwater crabs hatch to produce juvenile(hatchling) crabs.We provide here the first report and description of the continuous record of embryonic development from egg-laying up to hatching in the Chinese true freshwater crab Sinopotamon yangtsekiense Bott,1967(Potamoidea,Potamidae).Direct development(complete secondary embryonization) in S.yangtsekiense was observed to take 77 days and to include an additional embryonic phase(termed here the egg-juvenile-crab) that occurs in the embryo between the imprisoned megalopa and the newly-emerged juvenile(hatchling) crab.This is significant because the only other freshwater crab whose embryonic development has been studied in detail is Potamon fluviatilis(Potamidae) which takes 45-47 days and involves only nine embryonic stages.展开更多
[Objective] This study aimed to explore whether there is autotoxicity in tumorous stem mustard through studying the allelopathic effects of water extracts and decomposition liquids of tumorous stem mustard residues on...[Objective] This study aimed to explore whether there is autotoxicity in tumorous stem mustard through studying the allelopathic effects of water extracts and decomposition liquids of tumorous stem mustard residues on seed germination and seedling growth of tumorous stem mustard.[Method] With Fuza No.2 as the experimental material,the effects of different concentrations of leaf extract,root extract,7-d decomposition liquid,15-d decomposition liquid of tumorous stem mustard on seed germination and seedling growth of tumorous stem mustard were investigated.[Result] Compared with those in the control,the four kinds of 100% treatment solutions all significantly reduced the seed germination rate,seed germination vigor,root length,plant height and fresh weight of tumorous stem mustard(P<0.05),and significantly increased the malondialdehyde(MDA) content,catalase(CAT) activity,peroxidase(POD) activity and superoxide dismutase(SOD) activity of young seedlings of tumorous stem mustard;the allelopathic effects of the four kinds of water extracts and decomposition liquids on seed germination and root length of tumorous stem mustard were weakened with the decreased concentration;for the four kinds of water extracts and decomposition liquids,low-concentration treatment solutions promoted the increase of plant height and fresh weight,while high-concentration treatment solutions inhibited the increase of plant height and fresh weight of young seedlings of tumorous stem mustard;the allelopathic effect of leaf extract on seed germination of tumorous stem mustard was stronger than those of root extract and decomposition liquids,the allelopathic effects of decomposition liquids on seedling growth of tumorous stem mustard were stronger than those of water extracts,the inhibitory effect of leaf extract on seed germination and seedling growth of tumorous stem mustard were stronger than that of root extract,and the inhibitory effect of 15-d decomposition liquid on seed germination and seedling growth of tumorous stem mustard was stronger than that of 7-d decomposition liquid.[Conclusion] The water extracts and decomposition liquids of tumorous stem mustard residues had certain autotoxicity on seed germination and seedling growth of tumorous stem mustard,and their allelopathic effects had a concentration-dependent manner.It could be presumed that the autotoxicity of tumorous stem mustard is the main cause of continuous cropping obstacle.展开更多
[Objective] This study aimed to determine the interactive effects of supple- mental Ca amendment and salinity on germination of sweet sorghum seeds in saline solution culture medium, and investigate the effects of dif...[Objective] This study aimed to determine the interactive effects of supple- mental Ca amendment and salinity on germination of sweet sorghum seeds in saline solution culture medium, and investigate the effects of different combinations of Na/Ca ratio in saline soils on the early growth of sweet sorghum plants. [Method] A germi- nation test and a greenhouse pot experiment were conducted to assess the interac- tive effects of calcium addition to culture medium on the germination and seedling growth of sweet sorghum (Sorghum saccharatum Moench) in saline soils with a range of NaYCa ratios. In the germination test, seeds were treated with different combinations of five calcium levels [0, 5, 10, 15, and 20 mmol/L Ca(NO3)2] and five salinity levels (0, 50, 100, 150, and 200 mmol/L NaCI). In the greenhouse experi- ment, seeds were sown in potting soils containing 3 salinity levels (2.3, 4.7 and 7.0 dS/m) and three Na:Ca ratios (10:0, 10:1, and 5:1). [Result] In the germination test, Ca addition at 5 mmol/L promoted germination by 5.5%, 9.9%, and 17.0% at the 3.4, 6.7 and 10.1 dS/m salinity levels. The higher Ca level (10 mmol/L) also in- creased germination by 9.1% and 7.8% at the 3.4 and 6.7 dS/m salinity levels. Then even higher Ca addition at 15 and 20 mmol/L appeared to promote germina- tion when culture media had high salinity (10.1 and 13.4 dS/m). In the greenhouse pot experiment, saline soil amended with supplemental Ca at the 2.3 and 4.7 dS/m salinity levels significantly promoted early seedling growth, with an increase of 6.8% to 28.2% in plant height and 14.3% to 67.9% in whole plant weight. From 28 to 42 d after seeding, the relative growth of seedling was increased by Ca addition, with a reduction of 49.5% to 66.0% in plant height and 4.8% to 61.9% in whole plant weight. From 42 to 56 d after seeding, however, the relative growth of seedling was significantly inhibited by Ca amendment. [Conclusion] Results of this study indicate that appropriate supplemental Ca could improve sorghum germination and early seedling growth in saline soils.展开更多
文摘Fluctuations of levels of several endogenous plant hormones in isolated rice ( Oryza sativa ssp. japonica) embryos during early and mid-embryogenesis and early stages of germination were studied by enzyme-linked immunosorbent assay (ELISA). Embryos were collected at different days after pollination (DAP) and different days after imbibition (DAI) of mature seeds. The contents of gibberellin(1) (GA(1)), abscisic acid (ABA), isopentenyladenine and isopentenyladenosine ( iPAs), zeatin and zeatin riboside ( ZRs) were immunochemically assayed. The GA(1) level was the highest among all hormones tested. The variations of GA(1) levels were opposite with the ABA levels, with some exceptions. During early and mid-embryogenesis, the levels of GA(1) and ABA were the highest at 4 DAP. From 8 to 18 DAP, GA(1) level declined, whereas the ABA level increased. During germination, GA(1) level increased at 2 DAI whereas simultaneously the ABA content decreased. The highest ratio of GA(1)/ABA was observed at 2 DAI The levels of iPAs and ZRs were maxima in the embryos at 4 DAP, decreased to a very low level and maintained constant thereafter. Our results provide further evidence that GA(1) plays an important role in the early stages of embryo development and germination. The balance between GA(1) and ABA, rather than their absolute contents, controls these processes throughout the development, whereas iPAs and ZRs may play important roles in early embryogenesis. The use of isolated embryos as starting material avoids the usual interferences with other tissues such as the endosperm. In addition, this is the first report dealing with the hormonal balance of early-embryos in rice.
基金Supported by China Spark Program for Science and Technology(2011GA740072)Shandong Provincial Soft Scientific Research Project(2015RKC35001)Shandong Provincial Agricultural High-quality Seed Engineering(2016LZGC019)~~
文摘With Welsh Onion seeds employed as materials, effects of magnetized water on seed Germination were studied. The results showed the treatment of magnetized water soaking for 4 h promoted water absorption rate and amylase ac- tivities of seeds significantly, which accelerated the transformation process of en- dosperm starch to soluble sugar, resulting in emergence of 36 hours in advance under low temperature condition. Germination rate and germination potential of magnetized water soaking were higher than the contrast by 6.7% and 10.0%, which helped cultivate vigorous seedling.
文摘Objective] This study almed to soIve technical probIems in artificial breed-ing of Parashorea chinensis. [Method] The effects of different iI umination intensity and soiI moisture on seed germination rate and emergence of P. chinensis were in-vestigated. [Result] Under conditions of ill umination intensity of 40% and soiI mois-ture of 60%, the seeds of P. chinensis showed the highest germination rate. [Con-clusion] This study wiI provide some basic information for the ex-situ conservation, repopuIation and deveIopment and utiIization of P. chinensis.
基金Supported by Loudi City Science and Technology Project(2014-1)State Key Laboratory of Hybrid RiceKey Laboratory of Pesticide Harmless Application of Hunan Province~~
文摘The research used bioassay method to explore seed tolerance of Cd in terms of seed germination and seedling growth. Specifically, 12 rice varieties of three types were investigated under Cd stress, covering germination rate, shooting index, vigor index, seedling and shoot lengths, and fresh weights. The results showed that as Cd concentration grew, seed germination and seedling growth kept increasingly inhibited; germination index, vigor index, root length, shoot length and fresh weights went down; inhibition effects on seed germination and seedling growth were conventional rice〉two-line hybrid rice〉three-line hybrid ,rice. Shanyou 9588, Tianyou 998, Chuanxiang 8, and Y Liangyou 1 performed ~rongly in Cd tolerance; C Liangyou 651, Nei 5 You 263, Xiangwanxian 16, Huanghuazhan, Xiangwanxian 13, and Zhunliangyou 527 performed poorly in Cd tolerance, and Cd tolerance of rest treatments were moderate.
基金Supported by the 2010 Yangtze River Delta Joint Key Project of Anhui Province(10140702023)2012 Collegiate Innovation Training Program for the Students of Hefei University of Technology(2012CXCY394)+1 种基金National Natural Sciences Foundation of China(31171787)2010 Provincial Scientific Research Program of Anhui Higher Education Institutions(010AJZR0899)~~
文摘ObjectiveThis study aimed to investigate the characters of major hydrolase isozymes in wheat seeds. MethodThe spectra of amylase, esterase and proteolytic enzyme isozymes in the germ, endosperm and radicle were studied in detail during the germination process using the polyacrylamide gel electrophoresis(PAGE). ResultThe results indicated that isozymes of amylase and esterase changed obviously in the endosperm during the germination, while isozymes of proteolytic enzyme exhibited distinct variation in the germ and radicle. ConclusionThis study provides basic data for effeciently improving the germination rate of crop seeds in the future.
基金This work is Supported by CAPES Brazil. Open research laboratory of forest plant ecology NEFU. The State's tenth five-year "211 Project"-supported key academic discipline program of ECNU。
文摘Peltophorum dubium seeds provided by Anhembi, SP were scarified in 98% H2SO4 for 15 min to overcome mechani-cal dormancy. Seeds were primed in solutions of 0.2% Captan at 10 C and 27C, PEG 6000 -1.0 MPa at 10C and 27C, 0.5 mol KNO3, 0.75 Mol KNO3, 1.0 Mol KNO3. Eight treatments including the primed seeds and nonprimed seeds, five replicates with 100 seeds for each treatment, were set to 15-cm-Petri dish with double filter paper moistened with testing solution PEG in refrigerator at 27C. For the experiments of all the groups, osmotic potential were 0.0, -0.2, -0.4, -0.6, -0.8, -1.0, -1.2, and -1.4 MPa. P. dubium seeds were also set to water stress experiment in rolled paper with PEG solutions from 0.0 to -1.0 M Pa. Germination percentage decreased with the increase of PEG concentration. Control group had a better germination percentage than other groups. Germination hardly occurred in PEG -1.4 MPa.
基金This work was supported by the National Natural Science Foundation of China(No.30670172)by the Korea Foundation for International Cooperation of Science and Technology(K/C0S)through a grant provided by the Korean Ministry of Science and Technology.
文摘Previous studies have demonstrated the possible role of several aquaporins in seed germination. But systematic investigation of the role ofaquaporin family members in this process is lacking. Here, the developmental regulation of plasma membrane intrinsic protein (PIP) expression throughout germination and post-germination processes in rice embryos was analyzed. The expression patterns of the PIPs suggest these aquaporins play different roles in seed germination and seedling growth. Partial silencing of the water channel genes, OsPIP1;1 and OsPIP1:3, reduced seed germination while over-expression of OsPIP1:3 promoted seed germination under water-stress conditions. Moreover, spatial expression analysis indicates that OsPIP1:3 is expressed predominantly in embryo during seed germination. Our data also revealed that the nitric oxide (NO) donors, sodium nitroprusside (SNP) and S-nitrosoglutathione (GSNO), promoted seed germination; furthermore, the NO scavenger, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, inhibited germination and reduced the stimulative effects of SNP and GSNO on rice germination. Exogenous NO stimulated the transcription of OsPIP1:1, OsPIP1:2, OsPIP1:3 and OsPIP2:8 in germinating seeds. These results suggest that water channels play an important role in seed germination, acting, at least partly, in response to the NO signaling pathway.
文摘Seeds germination and seedling stages were studied on the legume seeds of Vicia angustifolia L. to reveal the effects of drought stress on germination char- acteristics and water absorption characteristics. The results showed that the rate of seed water uptake,germination percentage,germination index,vigor index,seedling height,root length and plant water content decreased with the increase of concen- tration of PEG stress. However,seedling and root dry weight and root/shoot ratio ini- tially increased followed by a decrease. The lowest osmotic potential threshold was -0.42 MPa.
文摘Soybean [Glycine max (L.)] is one of the most important protein and oil seed crop. In attention to time consuming and effect of uncontrolled agents like soil elements and hemisphere, study of tolerance in soybean to water stress during germination was investigated. Four soybean cultivars 'Williams, Linford, L 17 and M7' were screened for drought tolerance by treatment of PEG6000 concentration for induce osmotic potentials (0, -3, -6, -9 bar). A factorial experiment based on completely randomized design with three replications was conducted. Germination percentage, radicle and hypocotyls length, fresh and dry weight of radicle, hypocotyl and seedling, TWC%, MDG, rate of daily germination and percentage of abnormal seedling were measured. Variance analysis of data indicated that difference between osmotic potential had significant effect on all parameters except germination percentage. A significant reduction in fresh weight of radicle and seedling, percentage of abnormal seedlings was observed for the genotypes as the concentration of PEG increased. In interaction between cultivars and water stress level, Linford and M7 with less damage had the highest yield in fresh and dry weight of radicle, respectively. Drought is one of the most important abiotic limited potential in germination and primary growth on these cultivars.
基金Supported by National Natural Science Foundation of China(41071305)~~
文摘[Objective] This study aimed to investigate the effects of phosphine on germination and physiological characteristics of rice seeds. [Method] Simulation envi- ronments were conducted to study the effects of high-level phosphine on germination status and physiological characteristics of rice seeds and explore the early environ- mental and ecological effects of phosphine on rice growth in phosphorus cycle of paddy field. [Result] Experimental results showed that the increase of phosphine con- centration in the environment resulted in the decrease of germination rate and ger- mination potential by 11.11% and 19.71%, respectively. In addition, the activities of catalase (CAT) and peroxidase (POD) were reduced to 94.35% and 92.61%, respec- tively; the content of malondialdehyde (MDA) was maximally increased by 29.11%, indicating that both germination potential and growth condition of rice seeds were in- hibited under conditions of high-level phosphine. [Conclusion] This study provided theoretical basis for investigating the effects of phosphine on germination of rice seeds under natural environment.
基金Supported by the Shanghai Leading Academic Discipline Project(No.S30701)the Leading Academic Discipline Project of Shanghai Municipal Education Commission(No.J50701)
文摘The true freshwater crabs(Crustacea,Decapoda,Brachyura) are highly adapted to life in freshwater and complete their life cycle entirely independently of sea water.All true freshwater crabs exhibit direct development and lack the free-living larval forms(zoea and megalopa) typical of most other brachyurans.After a prolonged embryonic period(during which they pass through the typical brachyuran larval forms embryologically) the eggs of true freshwater crabs hatch to produce juvenile(hatchling) crabs.We provide here the first report and description of the continuous record of embryonic development from egg-laying up to hatching in the Chinese true freshwater crab Sinopotamon yangtsekiense Bott,1967(Potamoidea,Potamidae).Direct development(complete secondary embryonization) in S.yangtsekiense was observed to take 77 days and to include an additional embryonic phase(termed here the egg-juvenile-crab) that occurs in the embryo between the imprisoned megalopa and the newly-emerged juvenile(hatchling) crab.This is significant because the only other freshwater crab whose embryonic development has been studied in detail is Potamon fluviatilis(Potamidae) which takes 45-47 days and involves only nine embryonic stages.
基金Supported by National Natural Science Foundation of China(31470568)Scientific and Technological Research Program of Chongqing Municipal Education Commission(KJ1401204)Program for Innovation Team Building at Institutions of Higher Education in Chongqing(2013)
文摘[Objective] This study aimed to explore whether there is autotoxicity in tumorous stem mustard through studying the allelopathic effects of water extracts and decomposition liquids of tumorous stem mustard residues on seed germination and seedling growth of tumorous stem mustard.[Method] With Fuza No.2 as the experimental material,the effects of different concentrations of leaf extract,root extract,7-d decomposition liquid,15-d decomposition liquid of tumorous stem mustard on seed germination and seedling growth of tumorous stem mustard were investigated.[Result] Compared with those in the control,the four kinds of 100% treatment solutions all significantly reduced the seed germination rate,seed germination vigor,root length,plant height and fresh weight of tumorous stem mustard(P<0.05),and significantly increased the malondialdehyde(MDA) content,catalase(CAT) activity,peroxidase(POD) activity and superoxide dismutase(SOD) activity of young seedlings of tumorous stem mustard;the allelopathic effects of the four kinds of water extracts and decomposition liquids on seed germination and root length of tumorous stem mustard were weakened with the decreased concentration;for the four kinds of water extracts and decomposition liquids,low-concentration treatment solutions promoted the increase of plant height and fresh weight,while high-concentration treatment solutions inhibited the increase of plant height and fresh weight of young seedlings of tumorous stem mustard;the allelopathic effect of leaf extract on seed germination of tumorous stem mustard was stronger than those of root extract and decomposition liquids,the allelopathic effects of decomposition liquids on seedling growth of tumorous stem mustard were stronger than those of water extracts,the inhibitory effect of leaf extract on seed germination and seedling growth of tumorous stem mustard were stronger than that of root extract,and the inhibitory effect of 15-d decomposition liquid on seed germination and seedling growth of tumorous stem mustard was stronger than that of 7-d decomposition liquid.[Conclusion] The water extracts and decomposition liquids of tumorous stem mustard residues had certain autotoxicity on seed germination and seedling growth of tumorous stem mustard,and their allelopathic effects had a concentration-dependent manner.It could be presumed that the autotoxicity of tumorous stem mustard is the main cause of continuous cropping obstacle.
基金Supported by Priority Academic Program Development of Jiangsu Higher Education Institution,Natural Science Foundation of China(31171483)Fund for Returning Overseas Scholars(2011)+1 种基金Jiangsu Provincial Science Technology Support Program (BE2010307)the Start-up Project of Yangzhou University(2006 and 2009)
文摘[Objective] This study aimed to determine the interactive effects of supple- mental Ca amendment and salinity on germination of sweet sorghum seeds in saline solution culture medium, and investigate the effects of different combinations of Na/Ca ratio in saline soils on the early growth of sweet sorghum plants. [Method] A germi- nation test and a greenhouse pot experiment were conducted to assess the interac- tive effects of calcium addition to culture medium on the germination and seedling growth of sweet sorghum (Sorghum saccharatum Moench) in saline soils with a range of NaYCa ratios. In the germination test, seeds were treated with different combinations of five calcium levels [0, 5, 10, 15, and 20 mmol/L Ca(NO3)2] and five salinity levels (0, 50, 100, 150, and 200 mmol/L NaCI). In the greenhouse experi- ment, seeds were sown in potting soils containing 3 salinity levels (2.3, 4.7 and 7.0 dS/m) and three Na:Ca ratios (10:0, 10:1, and 5:1). [Result] In the germination test, Ca addition at 5 mmol/L promoted germination by 5.5%, 9.9%, and 17.0% at the 3.4, 6.7 and 10.1 dS/m salinity levels. The higher Ca level (10 mmol/L) also in- creased germination by 9.1% and 7.8% at the 3.4 and 6.7 dS/m salinity levels. Then even higher Ca addition at 15 and 20 mmol/L appeared to promote germina- tion when culture media had high salinity (10.1 and 13.4 dS/m). In the greenhouse pot experiment, saline soil amended with supplemental Ca at the 2.3 and 4.7 dS/m salinity levels significantly promoted early seedling growth, with an increase of 6.8% to 28.2% in plant height and 14.3% to 67.9% in whole plant weight. From 28 to 42 d after seeding, the relative growth of seedling was increased by Ca addition, with a reduction of 49.5% to 66.0% in plant height and 4.8% to 61.9% in whole plant weight. From 42 to 56 d after seeding, however, the relative growth of seedling was significantly inhibited by Ca amendment. [Conclusion] Results of this study indicate that appropriate supplemental Ca could improve sorghum germination and early seedling growth in saline soils.