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
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
Background： The occurrence of aspen trees increases the conservation value of mature conifer dominated forests. Aspens typically occur as scattered individuals among major tree species, and therefore the inventory of...Background： The occurrence of aspen trees increases the conservation value of mature conifer dominated forests. Aspens typically occur as scattered individuals among major tree species, and therefore the inventory of aspens is challenging. Methods： We characterized aspen populations in a boreal nature reserve using diameter distribution, spatial pattern, and forest attributes： volume, number of aspens, number of large aspen stems and basal area median diameter. The data were collected from three separate forest stands in Koli National Park, eastern Finland. At each site, we measured breast height diameter and coordinates of each aspen. The comparison of inventory methods of aspens within the three stands was based on simulations with mapped field data. We mimicked stand level inventory by locating varying numbers of fixed area circular plots both systematically and randomly within the stands. Additionally, we also tested if the use of airborne laser scanning （ALS） data as auxiliary information would improve the accuracy of the stand level inventory by applying the probability proportional to size sampling to assist the selection of field plot locations. Results： The results showed that aspens were always clustered, and the diameter distributions indicated different stand structures in the three investigated forest stands. The reliability of the volume and number of large aspen trees varied from relative root mean square error figures above 50% with fewer sample plots （5-10） to values of 25%-50% with ]0 or more sample plots. Stand level inventory estimates were also able to detect spatial pattern and the shape of the diameter distribution. In addition, ALS-based auxiliary information could be useful in guiding the inventories, but caution should be used when applying the ALS-supported inventory technique. Conclusions： This study characterized European aspen populations for the purposes of monitoring and management of boreal conservation areas. Our results suggest that if the number of sample plot展开更多
In this study, the vitrificated plants of hybrid aspen (Populus tremula× P.tremuloides) by micropropagation were used as the materials,and ELISA method was adopted to measure the content of endogenous plant hormo...In this study, the vitrificated plants of hybrid aspen (Populus tremula× P.tremuloides) by micropropagation were used as the materials,and ELISA method was adopted to measure the content of endogenous plant hormones in the plants. At the same time, the factors that influenced the vitrification of the plant as well as de-vitrification method were also studied by changing medium’s component, which was to provide useful information for commercial propagation of good hybrid clones of aspen. The results were as follows: 1)The ABA and IAA contents in the vitrificated plants were higher than those in the non-vitrificated plants obviously, and the GA content was little lower than that of the non-vitrificated plants. Therefore, the higher IAA or ABA content in the vitrificated plants was possibly the main reason for the vitrification of the plant.2)The ratios of endogenous plant hormones such as ABA/GA and IAA/GA in the vitrificated plants of hybrid aspen by tissue culture were higher than those in the non-vitrificated plants, which indicated that the equilibrium relationship among different endogenous hormones in vitrificated plants was deviated from the normal, then possibly resulting in the vitrification of the plant.展开更多
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.
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.
基金supported by by the strategic funding of the University of Eastern Finland
文摘Background： The occurrence of aspen trees increases the conservation value of mature conifer dominated forests. Aspens typically occur as scattered individuals among major tree species, and therefore the inventory of aspens is challenging. Methods： We characterized aspen populations in a boreal nature reserve using diameter distribution, spatial pattern, and forest attributes： volume, number of aspens, number of large aspen stems and basal area median diameter. The data were collected from three separate forest stands in Koli National Park, eastern Finland. At each site, we measured breast height diameter and coordinates of each aspen. The comparison of inventory methods of aspens within the three stands was based on simulations with mapped field data. We mimicked stand level inventory by locating varying numbers of fixed area circular plots both systematically and randomly within the stands. Additionally, we also tested if the use of airborne laser scanning （ALS） data as auxiliary information would improve the accuracy of the stand level inventory by applying the probability proportional to size sampling to assist the selection of field plot locations. Results： The results showed that aspens were always clustered, and the diameter distributions indicated different stand structures in the three investigated forest stands. The reliability of the volume and number of large aspen trees varied from relative root mean square error figures above 50% with fewer sample plots （5-10） to values of 25%-50% with ]0 or more sample plots. Stand level inventory estimates were also able to detect spatial pattern and the shape of the diameter distribution. In addition, ALS-based auxiliary information could be useful in guiding the inventories, but caution should be used when applying the ALS-supported inventory technique. Conclusions： This study characterized European aspen populations for the purposes of monitoring and management of boreal conservation areas. Our results suggest that if the number of sample plot
文摘In this study, the vitrificated plants of hybrid aspen (Populus tremula× P.tremuloides) by micropropagation were used as the materials,and ELISA method was adopted to measure the content of endogenous plant hormones in the plants. At the same time, the factors that influenced the vitrification of the plant as well as de-vitrification method were also studied by changing medium’s component, which was to provide useful information for commercial propagation of good hybrid clones of aspen. The results were as follows: 1)The ABA and IAA contents in the vitrificated plants were higher than those in the non-vitrificated plants obviously, and the GA content was little lower than that of the non-vitrificated plants. Therefore, the higher IAA or ABA content in the vitrificated plants was possibly the main reason for the vitrification of the plant.2)The ratios of endogenous plant hormones such as ABA/GA and IAA/GA in the vitrificated plants of hybrid aspen by tissue culture were higher than those in the non-vitrificated plants, which indicated that the equilibrium relationship among different endogenous hormones in vitrificated plants was deviated from the normal, then possibly resulting in the vitrification of the plant.
