Bud flushing is very important for the survival and growth of trees, a phenomenon matched each year with the annual course of temperature and the timing of bud flushing in the spring. Essentially it represents a serio...Bud flushing is very important for the survival and growth of trees, a phenomenon matched each year with the annual course of temperature and the timing of bud flushing in the spring. Essentially it represents a serious ecological and evolutionary tradeoff between survival and growth. The most suitable timing of bud burst permits trees to begin growth sufficiently early to take advantage of favorable spring conditions, but late enough to decrease the risks of tissue damage from late frost. In the present study bud burst spring phenology of poplar （Populus tremula and P. tremuloides） from eight different provenances, originating from Eu- rope and the USA, was observed during March and April, 2009. The experimental plot was located at Solling, Germany （51~44＇0＂ N, 9036＇0＇＇ E）. A six stage subjective scoring system of bud burst phenology was used to identify the phenological stages of the seed- lings, where each plant was observed twice a week. The aim of the study was to predict phenotypic variation in poplar, originating from regions between 42~ and 60~ N latitude, growing in similar environments. Timing of bud flushing of poplar was recorded. It was found that seedlings of provenance 3, which originated from 42.35~ N latitude, started and completed flushing significantly earlier than those of other provenances, while seedlings of provenance 5, originating from 54.29~ N latitude, started flushing very late and only a few plants reached top scoring at the end of the experimental period. Analysis of variance showed statistically highly signifi- cant differences （p 〈 0.05） in bud flushing among the provenances. The correlation between scoring and flushing periods was very strong within provenances although the flushing pattern differed among provenances （origin of the planted seedlings）. Bud flushing showed a negative correlation with the origin of the planted seedlings. Given the field experience gained with this experiment, it is recommended that seedlings from provenances 5 and 8 could 展开更多
Analysis of the properties of transgenic aspen clones with recombinant gene xyloglucanase sp-Xeg from fungi Penicillium canescens showed the presence of complex modifications both in the wood and the phenotype of plan...Analysis of the properties of transgenic aspen clones with recombinant gene xyloglucanase sp-Xeg from fungi Penicillium canescens showed the presence of complex modifications both in the wood and the phenotype of plants. Biometric analysis revealed an increase in the height of transgenic plants as compared to control plants. Increasing in the height of the shoot of 24.8%, 25% and 26% was observed for lines PtXIVXeg1a, PtXVXeg1a, PtXVXeg1b, respectively. Also there was an increase in the number of internodes in some transgenic clones. For the first time we showed the change in plants rhizogenesis with the recombinant gene xyloglucanase. In 10 of the 25 lines the rooting efficiency in vitro exceeded the control value. The maximum value of the rhizogenesis was fixed for line PtXVXeg1a (2.5 times higher than the control value). The mass of the root system for 6 of the 25 clones in the greenhouse was higher by 20% than the control value. The pentosan content decrease was also detected in all wood samples of transgenic plants. The obtained data of xyloglucanase activity and pentosan content generally correlated with phenotypic modifications.展开更多
In vitro culture of isolated cells from tissues and organs is sometimes used to preserve and reproduce unique genotypes of woody plants. The technique, however, requires regular subculturing which raises storage costs...In vitro culture of isolated cells from tissues and organs is sometimes used to preserve and reproduce unique genotypes of woody plants. The technique, however, requires regular subculturing which raises storage costs and creates risks for contamination and accumulation of somaclonal variations. We examined the effects of sugar composition of culture medium, the length of photoperiod, light intensity, and ambient temperature on the survival of plant material in vitro. The study was performed on 49 genotypes of Populus tremula (46 transgenic genotypes carrying GFP-, Xeg- and Gus-genes, and 3 control (wild-type) genotypes). It was shown that effective storage of plants was achieved through optimization of the combined effects of all storage parameters under study. Based on the experimental data, we developed a protocol for long-term in vitro storage of desirable genotypes without subculture and with a survival rate of up to 98%. The best results were obtained when the plant material was pre-cultured on a WPM medium containing 15 g/L sucrose, 7.5 g/L sorbitol and 7.5 g/L mannitol, and then stored at +4°C under a 24-hour light day cycle with only 8 hours of light per day and maximum light intensity of 2000 lux. Post-storage recovery was done by culturing on a medium containing 1 mg/L gibberellic acid. The developed method can be used for effective in vitro storage of the studied genotypes for up to 24 months without subculture.展开更多
基金supported by the Institute of Forest Genetics and Forest Tree Breedingthe Institute of Forest Botany, Georg-August-University, Gttingen,Germanyprovided by the university and a scholarship from the European Union
文摘Bud flushing is very important for the survival and growth of trees, a phenomenon matched each year with the annual course of temperature and the timing of bud flushing in the spring. Essentially it represents a serious ecological and evolutionary tradeoff between survival and growth. The most suitable timing of bud burst permits trees to begin growth sufficiently early to take advantage of favorable spring conditions, but late enough to decrease the risks of tissue damage from late frost. In the present study bud burst spring phenology of poplar （Populus tremula and P. tremuloides） from eight different provenances, originating from Eu- rope and the USA, was observed during March and April, 2009. The experimental plot was located at Solling, Germany （51~44＇0＂ N, 9036＇0＇＇ E）. A six stage subjective scoring system of bud burst phenology was used to identify the phenological stages of the seed- lings, where each plant was observed twice a week. The aim of the study was to predict phenotypic variation in poplar, originating from regions between 42~ and 60~ N latitude, growing in similar environments. Timing of bud flushing of poplar was recorded. It was found that seedlings of provenance 3, which originated from 42.35~ N latitude, started and completed flushing significantly earlier than those of other provenances, while seedlings of provenance 5, originating from 54.29~ N latitude, started flushing very late and only a few plants reached top scoring at the end of the experimental period. Analysis of variance showed statistically highly signifi- cant differences （p 〈 0.05） in bud flushing among the provenances. The correlation between scoring and flushing periods was very strong within provenances although the flushing pattern differed among provenances （origin of the planted seedlings）. Bud flushing showed a negative correlation with the origin of the planted seedlings. Given the field experience gained with this experiment, it is recommended that seedlings from provenances 5 and 8 could
文摘Analysis of the properties of transgenic aspen clones with recombinant gene xyloglucanase sp-Xeg from fungi Penicillium canescens showed the presence of complex modifications both in the wood and the phenotype of plants. Biometric analysis revealed an increase in the height of transgenic plants as compared to control plants. Increasing in the height of the shoot of 24.8%, 25% and 26% was observed for lines PtXIVXeg1a, PtXVXeg1a, PtXVXeg1b, respectively. Also there was an increase in the number of internodes in some transgenic clones. For the first time we showed the change in plants rhizogenesis with the recombinant gene xyloglucanase. In 10 of the 25 lines the rooting efficiency in vitro exceeded the control value. The maximum value of the rhizogenesis was fixed for line PtXVXeg1a (2.5 times higher than the control value). The mass of the root system for 6 of the 25 clones in the greenhouse was higher by 20% than the control value. The pentosan content decrease was also detected in all wood samples of transgenic plants. The obtained data of xyloglucanase activity and pentosan content generally correlated with phenotypic modifications.
文摘In vitro culture of isolated cells from tissues and organs is sometimes used to preserve and reproduce unique genotypes of woody plants. The technique, however, requires regular subculturing which raises storage costs and creates risks for contamination and accumulation of somaclonal variations. We examined the effects of sugar composition of culture medium, the length of photoperiod, light intensity, and ambient temperature on the survival of plant material in vitro. The study was performed on 49 genotypes of Populus tremula (46 transgenic genotypes carrying GFP-, Xeg- and Gus-genes, and 3 control (wild-type) genotypes). It was shown that effective storage of plants was achieved through optimization of the combined effects of all storage parameters under study. Based on the experimental data, we developed a protocol for long-term in vitro storage of desirable genotypes without subculture and with a survival rate of up to 98%. The best results were obtained when the plant material was pre-cultured on a WPM medium containing 15 g/L sucrose, 7.5 g/L sorbitol and 7.5 g/L mannitol, and then stored at +4°C under a 24-hour light day cycle with only 8 hours of light per day and maximum light intensity of 2000 lux. Post-storage recovery was done by culturing on a medium containing 1 mg/L gibberellic acid. The developed method can be used for effective in vitro storage of the studied genotypes for up to 24 months without subculture.
