An efficient genetic transformation system is a preparation for Rosa multi-flora Thunb. var. cathayensis Rehd. et Wils to diversify its flower color through ge-netic engineering. We firstly optimized the explants and ...An efficient genetic transformation system is a preparation for Rosa multi-flora Thunb. var. cathayensis Rehd. et Wils to diversify its flower color through ge-netic engineering. We firstly optimized the explants and culture conditions on callus induction, hormone concentrations and dark period of culture time on bud differentia-tions in particular, with sterilized seedlings to establish the regeneration system of R. multiflora. It showed that callus induction frequency reached 100% after the ex-plants being cultured in dark for 21 d when MS was chosen to be the initial culture medium. The bud differentiation rate was 48% after cal i being cultured under dark for 8 d on MS medium supplemented with TDZ （1.5 mg/L） and NAA （0.05 mg/L）. The cal i was used as the explants that were infected with Agrobacterium tumefa-ciens harboring a DFR-RNAi construct. The transformation rate reached as high as 50%. The establishment of a highly efficient rose gene transformation system out-lined in this report is prerequisite for genetic improvement in rose flower colors.展开更多
Ten-maize inbred lines of maize （Zea mays L.） with high-induction rate and proliferation ability of embryonic calli were selected from 70-maize inbred lines by immature embryo culturing. Some of the embryonic calli ...Ten-maize inbred lines of maize （Zea mays L.） with high-induction rate and proliferation ability of embryonic calli were selected from 70-maize inbred lines by immature embryo culturing. Some of the embryonic calli were transferred onto regeneration medium to examine the ability of regeneration, some were transformed via Agrobacterium tumifaciens C58 carrying intron-β-glucuronidase （gus） gene, and GV3301 carrying the green fluorescent protein （gfp） gene to study the susceptibility of different genotypes in maize to A. tumifaciens. All embryonic calli initiated from 10-maize inbred lines were able to regenerate into plantlets, and the regeneration frequencies of inbred lines 6010, 6038, 6015, 6051, and 6060 were 61.11%, 31.94%, 45%, 33.33%, and 56.94%, respectively, which were higher than that of other lines. Analysis of variance indicated that the susceptibility of the various genotypes in maize to A. tumifacien C58 showed a significant difference among each other, and the inbred lines 6010, 6015, 6051, 6050, 6058, 6060, 6069, 6077 were susceptible to A. tumifacien C58, of which frequency of gus expression were over 70%. Expression of GFP was observed in six-inbred lines （6050, 6015, 6051, 6058, 6069, 6077）. The inbred lines 6051, 6010, 6015, 6060, and 6050 had the high regeneration and the susceptibility to A. tumifaciens C58; and the inbred lines 6051, 6015, and 6060 had the high regeneration and the susceptibility to Agrobacterium tumifaciens GV3301.展开更多
Rockfalls can cause serious damage to people,property,facilities and transportation corridors.Furthermore,rockfalls are major hazards in mountain areas with negative impacts on individual trees and forested ecosystems...Rockfalls can cause serious damage to people,property,facilities and transportation corridors.Furthermore,rockfalls are major hazards in mountain areas with negative impacts on individual trees and forested ecosystems.We conducted a study of rockfall events on 117 mapped(91% of total trees in the stand with>1.3 m in height and>5 cm diameter at breast height)Turkish fir trees(Abies bornmuelleriana Mattf.)in a stand within the Kayaarkasi-Topular Village,Inebolu district, Kastamonu province of Turkey.The study site of 0.35 Ha is located on the transition zone of frequently passing rockfall fragments(～40 cm in diameter) generally causing healable injuries.Parameters of trees and injuries were recorded and analysed as to injury number,height and size.Bivariate correlation analysis were used to investigate the relationships between:a)diameter at breast height and number of injuries per tree,b)diameter at breast height and total injury size,c)the number of injuries and total injury size and d)the number of injuries per tree and distance from the source of the rockfall area.Results indicate that the average height of injury,average number of injuries and average injury area to be 81.3 cm(STDEV:49.8),7.46(STDEV:4.4)and 628.6 cm2 (STDEV:678.2),respectively.In total 84% of all injuries were recorded within 160°sector at the upslope side of trees and callus tissue that had closed wounds was observed in 79.1% of all injuries. Furthermore 14.5% of injured trees had callus tissue in the process of closing wounds while 6.4% of injuries had not formed any callus tissue.The most common injury types were bark and wood injuries. Bivariate correlation analysis indicated strong relationships between diameter at breast height and the number of injuries(rs=0.524),injury number and total injury area(rs=0.653)and distance from rockfall area and injury numbers relations(rs=-0.518).A weaker relationship was found between diameter at breast height and total injury area(rs=0.363).These results indicate that bigger trees are more prone to rockfall injuries.As expected,trees further from the rockfall area seem to be less prone to rockfall injuries.From our results,it can be inferred that the protection of people and property can be increased through the maintanance of forest in areas immediately below areas prone to rockfall.This stand is still managed in selective forest management system.In order to protect the settlement at the deposition zone it has to manage for protective goals with uneven-aged and multilayered stand structure.展开更多
Several protocols have been published for somatic embryogenesis in maize. It is essential to compare different protocols on selected germplasm at initial stages of tissue culture to identify a protocol that would yiel...Several protocols have been published for somatic embryogenesis in maize. It is essential to compare different protocols on selected germplasm at initial stages of tissue culture to identify a protocol that would yield optimum results. The ultimate goal is to use in vitro system for selecting and generating stress tolerant maize germplasm. Immature embryos of the elite inbred lines of maize （87014 ×Z28-11 and POP43SRS5-57） were cultured on three different semi-solid media （0.5% agar） and the effectiveness of the media for somatic embryogenesis assessed over a period two weeks of sub-culturing. A significant difference was observed among the media in proportion of potentially embryogenic calli and callus cluster size at 1 and 2 weeks after culturing. N6 medium supplemented with casaminoacid （100 mg/L）, 2, 4-dichlorophenoxy acetic acid （1 mg/L）, L-proline （25 mM） and sucrose （2%）, and Murashige and Skoog （MS） medium supplemented with 2, 4-D （2 mg/L） and sucrose （3%） gave higher proportion of potentially embryogenic calli and callus size than MS medium supplemented with casaminoacids （100 mg/L）, 2, 4-D （2 mg/L）, abscissic acid （3.3μM）, and silver nitrate （195 μM） and sucrose （3%）. The difference between genotypes is not significant展开更多
基金Supported by the State Bureau of Forestry 948 Project(P2009-4-25)~~
文摘An efficient genetic transformation system is a preparation for Rosa multi-flora Thunb. var. cathayensis Rehd. et Wils to diversify its flower color through ge-netic engineering. We firstly optimized the explants and culture conditions on callus induction, hormone concentrations and dark period of culture time on bud differentia-tions in particular, with sterilized seedlings to establish the regeneration system of R. multiflora. It showed that callus induction frequency reached 100% after the ex-plants being cultured in dark for 21 d when MS was chosen to be the initial culture medium. The bud differentiation rate was 48% after cal i being cultured under dark for 8 d on MS medium supplemented with TDZ （1.5 mg/L） and NAA （0.05 mg/L）. The cal i was used as the explants that were infected with Agrobacterium tumefa-ciens harboring a DFR-RNAi construct. The transformation rate reached as high as 50%. The establishment of a highly efficient rose gene transformation system out-lined in this report is prerequisite for genetic improvement in rose flower colors.
基金This work was supported by the National Natural Sciences Foundation of China (No. 30370889)the Program for Changjiang Scholars and Innovative Research Team in University of China (No. IRT0453)+3 种基金Beijing Agricultural Innovative Platform-Beijing Natural Science Fund Programthe National High-tech R&D Program of China (No. 2006 AA100103)the National Key Technolo-gies R&D Program (No. 2006 BAD01A03)the Program of the National Ministry of Agriculture (No. 2003-Q03)
文摘Ten-maize inbred lines of maize （Zea mays L.） with high-induction rate and proliferation ability of embryonic calli were selected from 70-maize inbred lines by immature embryo culturing. Some of the embryonic calli were transferred onto regeneration medium to examine the ability of regeneration, some were transformed via Agrobacterium tumifaciens C58 carrying intron-β-glucuronidase （gus） gene, and GV3301 carrying the green fluorescent protein （gfp） gene to study the susceptibility of different genotypes in maize to A. tumifaciens. All embryonic calli initiated from 10-maize inbred lines were able to regenerate into plantlets, and the regeneration frequencies of inbred lines 6010, 6038, 6015, 6051, and 6060 were 61.11%, 31.94%, 45%, 33.33%, and 56.94%, respectively, which were higher than that of other lines. Analysis of variance indicated that the susceptibility of the various genotypes in maize to A. tumifacien C58 showed a significant difference among each other, and the inbred lines 6010, 6015, 6051, 6050, 6058, 6060, 6069, 6077 were susceptible to A. tumifacien C58, of which frequency of gus expression were over 70%. Expression of GFP was observed in six-inbred lines （6050, 6015, 6051, 6058, 6069, 6077）. The inbred lines 6051, 6010, 6015, 6060, and 6050 had the high regeneration and the susceptibility to A. tumifaciens C58; and the inbred lines 6051, 6015, and 6060 had the high regeneration and the susceptibility to Agrobacterium tumifaciens GV3301.
文摘Rockfalls can cause serious damage to people,property,facilities and transportation corridors.Furthermore,rockfalls are major hazards in mountain areas with negative impacts on individual trees and forested ecosystems.We conducted a study of rockfall events on 117 mapped(91% of total trees in the stand with>1.3 m in height and>5 cm diameter at breast height)Turkish fir trees(Abies bornmuelleriana Mattf.)in a stand within the Kayaarkasi-Topular Village,Inebolu district, Kastamonu province of Turkey.The study site of 0.35 Ha is located on the transition zone of frequently passing rockfall fragments(～40 cm in diameter) generally causing healable injuries.Parameters of trees and injuries were recorded and analysed as to injury number,height and size.Bivariate correlation analysis were used to investigate the relationships between:a)diameter at breast height and number of injuries per tree,b)diameter at breast height and total injury size,c)the number of injuries and total injury size and d)the number of injuries per tree and distance from the source of the rockfall area.Results indicate that the average height of injury,average number of injuries and average injury area to be 81.3 cm(STDEV:49.8),7.46(STDEV:4.4)and 628.6 cm2 (STDEV:678.2),respectively.In total 84% of all injuries were recorded within 160°sector at the upslope side of trees and callus tissue that had closed wounds was observed in 79.1% of all injuries. Furthermore 14.5% of injured trees had callus tissue in the process of closing wounds while 6.4% of injuries had not formed any callus tissue.The most common injury types were bark and wood injuries. Bivariate correlation analysis indicated strong relationships between diameter at breast height and the number of injuries(rs=0.524),injury number and total injury area(rs=0.653)and distance from rockfall area and injury numbers relations(rs=-0.518).A weaker relationship was found between diameter at breast height and total injury area(rs=0.363).These results indicate that bigger trees are more prone to rockfall injuries.As expected,trees further from the rockfall area seem to be less prone to rockfall injuries.From our results,it can be inferred that the protection of people and property can be increased through the maintanance of forest in areas immediately below areas prone to rockfall.This stand is still managed in selective forest management system.In order to protect the settlement at the deposition zone it has to manage for protective goals with uneven-aged and multilayered stand structure.
文摘Several protocols have been published for somatic embryogenesis in maize. It is essential to compare different protocols on selected germplasm at initial stages of tissue culture to identify a protocol that would yield optimum results. The ultimate goal is to use in vitro system for selecting and generating stress tolerant maize germplasm. Immature embryos of the elite inbred lines of maize （87014 ×Z28-11 and POP43SRS5-57） were cultured on three different semi-solid media （0.5% agar） and the effectiveness of the media for somatic embryogenesis assessed over a period two weeks of sub-culturing. A significant difference was observed among the media in proportion of potentially embryogenic calli and callus cluster size at 1 and 2 weeks after culturing. N6 medium supplemented with casaminoacid （100 mg/L）, 2, 4-dichlorophenoxy acetic acid （1 mg/L）, L-proline （25 mM） and sucrose （2%）, and Murashige and Skoog （MS） medium supplemented with 2, 4-D （2 mg/L） and sucrose （3%） gave higher proportion of potentially embryogenic calli and callus size than MS medium supplemented with casaminoacids （100 mg/L）, 2, 4-D （2 mg/L）, abscissic acid （3.3μM）, and silver nitrate （195 μM） and sucrose （3%）. The difference between genotypes is not significant
