bHLH transcription factors,widely exist in various plants,and are vital for the growth and development of these plants.Among them,many have been implicated in anthocyanin biosynthesis across various plants.In the pres...bHLH transcription factors,widely exist in various plants,and are vital for the growth and development of these plants.Among them,many have been implicated in anthocyanin biosynthesis across various plants.In the present study,a PdbHLH57 gene,belonging to the bHLH IIIf group,was characterized,which was isolated and cloned from the colored-leaf poplar‘Zhongshancaiyun’(ZSCY).The cDNA sequence of PdbHLH57 was 1887 base pairs,and the protein encoded by PdbHLH57 had 628 amino acids,the isoelectric point and molecular weight of which were 6.26 and 69.75 kDa,respectively.Through bioinformatics analysis,PdbHLH57 has been classified into the IIIf bHLH subgroup,with many members of this subgroup known to participate in anthocyanin biosynthesis.The subcellular localization analysis conducted in the leaf protoplasts of‘ZSCY’revealed that the PdbHLH57 protein is specifically localized in the nucleus.The transcription activation analysis was also conducted,and the results showed that the PdbHLH57 protein had self-transcription activation.To better explore the functions of the PdbHLH57 protein,two parts of this protein(PdbHLH57-1,PdbHLH57-2)were split to detect their transcriptional activation activity.The results indicated that PdbHLH57-1(1-433aa)had self-transcription activation,and PdbHLH57-2(433-628aa)had no transcription activation.The expression of PdbHLH57 peaked in June during different developmental stages in‘ZSCY’,and it was most highly expressed in the phloem among various tissues.These findings offer a basis for understanding the role of PdbHLH57 in colored-leaf poplar.展开更多
A geomagnetic field is a significant factor dur-ing the growth and development of trees.Changes in the magnetic field(MF)will result in reactions at the biochemi-cal,molecular,cellular and gene levels.However,it is no...A geomagnetic field is a significant factor dur-ing the growth and development of trees.Changes in the magnetic field(MF)will result in reactions at the biochemi-cal,molecular,cellular and gene levels.However,it is not clear how a magnetic field affects metabolism and home-ostasis under stressful conditions such as salinity.In this study,a novel method was developed of a static magnetic field(SMF)to investigate magnetobiological changes in trees.The results show that pre-treatment of poplar(Popu-lus×euramericana‘Neva’)cuttings with a static magnetic field significantly mitigated the negative effects of salinity stress on their growth and physiological activities.Bio-chemical assays revealed that several chemical messengers,including hydrogen peroxide(H2O2)and O_(2)^(·-),were sig-nificantly improved in roots treated with salt,implying an increase reactive oxygen species.A static magnetic field also significantly increased proline concentrations,soluble protein contents,and CAT and SOD activities.Electrophysiological experiments further revealed that pre-treatment with a static magnetic field remarkably decreased salt-induced Na^(+)influx and H^(+)efflux which control plant salt tolerance.In pharmacological experiments,because the Na^(+)/H^(+)cor-relation was closely related to the SMF-activated plasma membrane and Na^(+)antiporter activity alleviated the mas-sive accumulation of salt-induced reactive oxygen spe-cies(ROS)within the roots.In addition,a static magnetic field dramatically increased the transcriptional activity of stress-responsive genes,including PtrRBOHD and PtrHA5.Together,these results indicate that SMF reduced Na^(+)influx by activating Na^(+)/H^(+)antiporters and plasma membrane H^(+)-ATPase to effectively maintain homeostasis by regu-lating the reactive oxygen species system and cytoplasmic osmotic potential.Ultimately,these static magnetic field methods improved salt tolerance in poplar cuttings,and,for future research,similar methods could be applied to other plants.展开更多
Partially modified Bt Cry1Ac gene and the arrowhead proteinase inhibitor (API) gene were used to construct a plant transformation vector pBtiA and this construct was transferred into the genome of the hybrid popla...Partially modified Bt Cry1Ac gene and the arrowhead proteinase inhibitor (API) gene were used to construct a plant transformation vector pBtiA and this construct was transferred into the genome of the hybrid poplar 741 [ Populus alba L.×( P. davidiana Dode+ P. simonii Carr.)× P. tomentosa Carr.] by Agrobacterium _ mediated transformation. Ten kanamycin resistant plants have been regenerated. Upon insect bioassay using Clostera anachoreta (Fabricius), three of the examined plants were demonstrated to be highly resistant to the testing insects. The mortality of insect larvae on one plant was higher than 90% in 6 days after infestation and the growth of the survival larvae were seriously inhibited. Results of PCR and Southern blot analysis indicated that both Bt Cry1Ac gene and API gene were integrated as a single copy into the genomes of these three plants when Cry1Ac gene fragment was used as the probe. Protein dot blot immunoassay and ELISA analysis revealed that at least the Cry1Ac protein was produced in these three transgenic plants and the expression levels were estimated to be approximately 0.015% of the leaf total soluble protein. This is the first report on insect resistant transgenic hybrid poplar 741 that expresses two insecticidal protein genes.展开更多
The cDNA fragment encoding caffeic acid 3_O_methyltransferase (COMT) in Chinese white poplar ( Populus tomentosa Carr.) was isolated and cloned by RT_PCR technique. The size of the cDNA fragment is 1 080 bp, which alm...The cDNA fragment encoding caffeic acid 3_O_methyltransferase (COMT) in Chinese white poplar ( Populus tomentosa Carr.) was isolated and cloned by RT_PCR technique. The size of the cDNA fragment is 1 080 bp, which almost covers the whole cDNA_encoding region. Authors’ cDNA fragment in P. tomentosa shares 98.7% homology with the reported corresponding cDNA in the P. tremuloids at nucleotide level, 99.4% homology at amino acid level, respectively. The analysis of Northern dot hybridization showed that COMT is expressed specifically in the developing secondary xylem of stem during the season of xylem differentiation, which means the linkage between the gene expression for a monolignol biosynthetic enzyme and seasonal regulation of xylem development in woody plant.展开更多
Codon usage is the selective and nonrandom use of synonymous codons to encode amino acids in genes for proteins. The analysis of codon usage may improve the understanding of cocion preferences between different specie...Codon usage is the selective and nonrandom use of synonymous codons to encode amino acids in genes for proteins. The analysis of codon usage may improve the understanding of cocion preferences between different species and allow to rebuild the codons of exogenous genes to increase the expression efficiency of exogenous genes, Here, codon DNA sequence （CDS） of four poplar species, including Populus tremuloides Michx., P. tomentosa Carr., P. deltoides Marsh., and P. trichocarpa Torr. ＆ Gray., is used to analyze the relative frequency of synonymous codon （RFSC）. High-frequency codons are selected by high-frequency （HF） codon analysis. The results indicate that the codon usage is common for all four poplar species and the codon preference is quite similar among the four poplar species. However, CCT encoding for Pro, and ACT coding for Thr are the preferred codons in P. tremuloides and P. tomentosa, whereas CCA coding for Pro, and ACA coding for Thr are preferred in P. deltoides and P. trichocarpa The codons such as TGC coding for Cys, TTC coding for Phe, and AAG coding for Lys, are preferred in the poplar species except P trichocarpa. GAG coding for Glu is preferred only in P deltoides, while the other three poplar species prefer to use GAA. The commonness of preferred codon allows exogenous gene designed by the preferred cocion of one of the different poplar species to be used in other poplar species.展开更多
The microfibril angle of seven poplar clones was determined by using X-ray diffraction technique. Microfibril angle, wood basic density, fiber length, fiber width and cellulose content were assessed for every growth r...The microfibril angle of seven poplar clones was determined by using X-ray diffraction technique. Microfibril angle, wood basic density, fiber length, fiber width and cellulose content were assessed for every growth ring at breast height for all sample trees. Significant variation in microfibril angle was observed among growth rings. Mean microfibril angle (MFA) at breast height varied from 7.8?to 28?between growth rings with cambial age and showed a consistent pith-to-bark trend of decline an-gles. Analysis of variance also indicated that there were significant differences in wood basic density, fiber length, fiber width and cellulose content between the growth rings, which had an increasing tendency from pith to bark. Correlations between MFA and examined wood properties were predominantly large and significant negative (?0.01), and the coefficients were -0.660 for cellulose content, -0.586 for fiber length, -0.516 for fiber width and -0.450 for wood basic density, respectively. Regression analysis with linear and curve estimation indicated that a quadratic function showed the largest R2 and the least standard error for describing the relationships between microfibril angle and measured wood properties, and the correlation coefficients were over -0.45 (n=125). The results from this study suggested that microfibril angle would be a good characteristic for improvement in the future breeding program of poplars.展开更多
The leaves of Bt (Bacillus thuringiensis) transgenic poplar (Populus nigra L.) and CpTI (Cowpea trypsin inhibitor) transgenic poplar ((P. tomentosa×P. bolleana)×P. Tomentosa) were taken to feed the 4th-5th-i...The leaves of Bt (Bacillus thuringiensis) transgenic poplar (Populus nigra L.) and CpTI (Cowpea trypsin inhibitor) transgenic poplar ((P. tomentosa×P. bolleana)×P. Tomentosa) were taken to feed the 4th-5th-instar larvae of American white moth (Hyphantria cunea (Drury)) for determination of the activities of the protective enzyme system inside larvae’s body. The physiological and biochemical effects of the transgenic poplars on the larvae were studied. The results showed that the two kinds of transgenic poplars had similar effects on the protective enzyme system in the midgut of larvae. The activities of superoxide dismutase, catalase, and peroxidase in midgut of the larvae increased gradually, reached the highest value at a certain time, and then decreased suddenly. For the larvae that were fed with the leaves of Bt transgenic poplar, the peak value of superoxide dismutase and catalase presented at the time of 24-h feeding, while the peak of peroxidase took place at the time of 12-h feeding. The activities of these protective enzymes for the larvae that were fed with leaves of CpTI transgenic poplar peaked 12 h later than that of those fed with leaves of Bt transgenic poplar. The comparison of activities of the protective enzymes was also carried out between the larvae with different levels of intoxication. It was found that the activities of protective enzyme of the seriously intoxicant larvae were higher than that of the lightly intoxicant larvae. This difference was more obvious in the group treated with CpTI transgenic poplar.展开更多
A study was conducted to evaluate the soil nutrient status of poplar plantation by Soil Nutrient Systematic Approach (SNSA) in Jianghan Plain, Hubei Province, China. Soil physiochemical properties were analyzed in lab...A study was conducted to evaluate the soil nutrient status of poplar plantation by Soil Nutrient Systematic Approach (SNSA) in Jianghan Plain, Hubei Province, China. Soil physiochemical properties were analyzed in laboratory through collection soil samples of study site. Ten treatments of application different fertilizers were designed such as CK, optimum treatment (N, P, K, Zn), N(P, K, Zn), P(N, K, Zn), K(N, P, Zn), +Mg(N, P, K, Zn, Mg), Zn (N,P,K), +2P(N, 2P, K, Zn), +2K(N, P, 2K, Zn), and 2N+2P+2K(2N, 2P, 2K, Zn) for field experiment to test the effect on tree height, diameter (DBH) growth, and dry weight of poplar. The results showed that there was no significant difference in tree heights between treatments with different fertilizers, diameter growth of poplar trees in treatments of lack of N and Zn was significantly slower than that of trees in optimum treatment, and dry weight of poplar dropped significantly for treatment of CK as well as treatments without application N and Zn. It is concluded that N and Zn were main limiting factor for poplar growth. Results from laboratory analysis and field experiment were uniform per-fectly, which proved that SNSA was reliable in evaluating soil nutrient status of poplar plantation.展开更多
Poplars are among the most important deciduous tree species in China. China is replete with natural resources of poplars. Poplars have a number of good characteristics, including fast growth rate, high yield, many use...Poplars are among the most important deciduous tree species in China. China is replete with natural resources of poplars. Poplars have a number of good characteristics, including fast growth rate, high yield, many uses, easiness of tissue culture and small gene group that make them well suited as a model system for the application of genetic engineering in forest trees. In the last decade, much progress has been made in genetic improvement of poplar species in China. Modern biotechnology is an important tool for genetic improvement in forest trees, and its applications to genetic improvement in poplars, which covers genetic transformation, gene expression, construction of genetic linkage map, QTLs (quantitative trait loci) identification and molecular assisted selection are reviewed in this paper. At the same time, the existing problems and outlook about the application of modern biotechnology to genetic improvement in forest trees are also discussed.展开更多
[Objective]The paper was to study the effect of continuous cropping on leaf nutrient and growth of different species of poplar plantation.[Method] The tree height,diameter at breast height（DBH）,volume of different g...[Objective]The paper was to study the effect of continuous cropping on leaf nutrient and growth of different species of poplar plantation.[Method] The tree height,diameter at breast height（DBH）,volume of different generations and species of poplar plantation in poplar production area in northern Jiangsu Province,as well as TN,TP and TK content in their leaves were determined through field investigation and indoor experiment.[Result] With the increasing generation,the changes of TN,TP and TK content in the leaves of different ages of two varieties of forest stand were also different.However,with the increasing tree ages,TN,TP and TK contents in leaves showed decrease trend.With the increasing generation,the changes of tree height of I-69 and I-72 poplar showed the similar trend.The effect of increasing generation on tree height of 7-year-old and 10-year-old poplar was relatively stable,showing decrease trend from generation to generation.The tree height of 4-year-old poplar first increased and then decreased with the increasing generation.The changes of DBH along with different generations were basically consistent with the changes of tree height.With the increasing cultivation generations,the volume of 7-year-old and 10-year-old poplar decreased with significant difference.[Conclusion ] The result provided basis for rational fertilization and management of poplar plantation,improvement of productivity of poplar plantation,and achievement of sustainable management of plantation.展开更多
Through the methods of correlation analysis and main factor analysis, the relationship between the poplar INA bacte-rial canker and circumstances was analyzed and 9 main factors for affecting the disease were selected...Through the methods of correlation analysis and main factor analysis, the relationship between the poplar INA bacte-rial canker and circumstances was analyzed and 9 main factors for affecting the disease were selected. Based on the compre-hensive analysis of main factors and induced factors, the standard for risk grades of this disease was promoted and northeast region of China was divided into 4 districts with different risk grades: seriously occurring district, commonly occurring district, occasionally occurring district, and un-occurring district. Nonlinear regression analysis for six model curves showed that the Richard growth model was suitable for describing the temporal dynamics of poplar INA bacterial canker. By stepwise variable selection method, the multi-variable linear regression forecasting equation was set up to predict the next year抯 disease index, and the GM (1,1) model was also set up by grey method to submit middle or long period forecast.展开更多
Through five years (1996-2000) experiment, the growth characteristics and resistance to insect and cold of the seven poplar varieties including P. po pularis, P. opera, P. pseudo-simonii, P. beijinensis, P. bolleana,...Through five years (1996-2000) experiment, the growth characteristics and resistance to insect and cold of the seven poplar varieties including P. po pularis, P. opera, P. pseudo-simonii, P. beijinensis, P. bolleana, P. ( eurameri cana and P. simonii, which were planted in loess hilly land in northwest Shanxi Province, were tested under different planting densities and site conditions. A randomized block design and three times repetition were adopted in the test. Bas ed on the test results in arid and cold area of the northwest Shanxi, the hybrid poplar trees taking Populus cathaysna as their female parent could be selected for afforestation, such as P. popularis and P. opera, and the growing space of s ingle plant should be larger than 20 m2. P. bolleana as an introduced tree speci es grows well in this area, but its growth is likely affected by ground water co ndition. On the site with relatively abundant soil water, P. bolleana usually su ffer from frost crack at its trunk base. As a result, P. bolleara is suited to p lanting in the site where is short of soil water. P. x euramericana is not suita ble for large-scale afforestation, especially in arid slopes and ridges of loess hilly land .展开更多
An experimental area of poplar was established in Songyuan of Jilin Province in 1999 for testing the resistance of different poplar stains to Saperda poplnea. Incidence of S. poplnea on ten poplar strains were investi...An experimental area of poplar was established in Songyuan of Jilin Province in 1999 for testing the resistance of different poplar stains to Saperda poplnea. Incidence of S. poplnea on ten poplar strains were investigated, and the main trophic component of branches of these poplar trees were measured and analyzed in April 2001. The results showed that there existed significant difference in population size of S. poplnea on different poplar strains, and the branches of these poplar strains have significant difference in nutrient component and content of amino acids. The population size of this pest had a significantly positive correlation with dissolvable total sugar and water content but had no significant correlation with content of total nitrogen and protein nitrogen.展开更多
Poplar is one of the dominant tree species for the establishment of fast growing plantations in Shandong Province. Eighteen poplar clones belonging to Populus aigeiros section were introduced from Italy, Turkey and do...Poplar is one of the dominant tree species for the establishment of fast growing plantations in Shandong Province. Eighteen poplar clones belonging to Populus aigeiros section were introduced from Italy, Turkey and domestic regions. Populus deltoides cv. 慙ux?I-69/55 (I-69), which was widely used in Shandong Province, China, was taken as control clone (I-69). Following a randomized complete block design, seedling test and controlled afforestation trials were carried out at Juxian County, Caoxian County and Laiyang City. The results showed that the poplar clone (Populus ?euramericana cv. ?02/74?, namely 102/74, performed well both in terms of adaptability and growth rate. The mean height of 13.9 m (H), diameter at breast height of 18.0 cm (DBH) and volume growth of 0.1445 m3 (V) were 2.2 %, 21.6% and 52.9 % higher than those of I-69 (CK), respectively, at the age of 5 years at three experimental sites. Moreover, the clone can be propagated easily and showed high resistance to poplar disease, pest as well as salinity and had longer growing period. Furthermore, wood basic density and fiber length of new poplar clone (102/74) were as same as I-69 (CK). It was concluded that the selected clone (102/74) was ideal for the estab-lishment of fast-growing poplar plantations, especially for the pulpwood plantations in Shandong Province.展开更多
The change of microbial community characteristics in the different rhizo- sphere zones of hybrid poplar （Populusdeltoidsxnigra, DN34） under atrazine stress were investigated by rhizo-boxes and Biolog system in a gre...The change of microbial community characteristics in the different rhizo- sphere zones of hybrid poplar （Populusdeltoidsxnigra, DN34） under atrazine stress were investigated by rhizo-boxes and Biolog system in a greenhouse experiment, with sublimed sulfur and calcium hydroxide as soil pH regulators. Data from the measurement by the Biolog ECO plate demonstrated that the value of average well color development （AWCD） and the carbon source utilization of soil microorganisms in the treatments with pH regulators were promoter than CK during the initial 30 days; while the results from the 90 days indicated that the activity and the carbon source utilization of soil microbes in acid regulator treatment began to fall down, even lower than that of poplar implant treatment, then the alkaline treatment could still stimulate and promote the activity and the carbon source utilization ability of soil microbes. Overall, the activity and community structure of soil microbes in rhizo- sphere zones of atrazine-contaminated soil did not show steady regularity during the phytoremediation process by using hybrid poplars. For the reason that the Biolog E- CO plate, which only had 31 kinds of carbon sources, could not really indicate the detail information about the function diversity of community structure of soil mi- crobes. So it＇s essential for us to take more sophisticated analysis tools for further study.展开更多
Based on the data of stand investigation and stem analysis, the effects of climate factors on the poplar protection forest increment in the riverbank field of the Dalinghe and Xiaolinghe rivers of Liaoning Province, C...Based on the data of stand investigation and stem analysis, the effects of climate factors on the poplar protection forest increment in the riverbank field of the Dalinghe and Xiaolinghe rivers of Liaoning Province, China were studied by step-wise regression procedure and grey system theories and methods. A regression model reflecting the correlation between the height increment of poplar protection forest and climatic factors was developed. The order of grey relevance for the effect of climatic factors on the height increment of poplar protection forest is: light>water>heat, and it could be interpreted that the poplar increment was mainly influenced by light factor, water factor, and heat factor. This result will provide scientific basis for the in-tensive cultivation and regeneration of the poplar protection forest in riverbank field in similar regions in China.展开更多
lnoculation experiment .was made for 15 poplar species to determine their resistance to Mirssonina brunneaby the agar leaf-disc techniquc and the water-culture shoots technique The results show that Populus simonii an...lnoculation experiment .was made for 15 poplar species to determine their resistance to Mirssonina brunneaby the agar leaf-disc techniquc and the water-culture shoots technique The results show that Populus simonii and nigravar. theveslina are very susceptible to the disease:P. davidiana and P.koreana are slightly reslstant to the disease P. us-suriensis has high resistance. and the others remain moderate resistance. Experiments are also made for healthy leaves toanalysis the inorganic element content and water Content. And the results show that the contents of Fe and Ca are remarkblynegativcly related to the resistance of poplars to Marssonina brunnea.展开更多
基金supported by the Natural Science Foundation of Jiangsu Province,China(BK20242007)the Natural Science Foundation of China(32271916)the Jiangsu Agricultural Science and Technology Innovation Fund[CX(24)3048].
文摘bHLH transcription factors,widely exist in various plants,and are vital for the growth and development of these plants.Among them,many have been implicated in anthocyanin biosynthesis across various plants.In the present study,a PdbHLH57 gene,belonging to the bHLH IIIf group,was characterized,which was isolated and cloned from the colored-leaf poplar‘Zhongshancaiyun’(ZSCY).The cDNA sequence of PdbHLH57 was 1887 base pairs,and the protein encoded by PdbHLH57 had 628 amino acids,the isoelectric point and molecular weight of which were 6.26 and 69.75 kDa,respectively.Through bioinformatics analysis,PdbHLH57 has been classified into the IIIf bHLH subgroup,with many members of this subgroup known to participate in anthocyanin biosynthesis.The subcellular localization analysis conducted in the leaf protoplasts of‘ZSCY’revealed that the PdbHLH57 protein is specifically localized in the nucleus.The transcription activation analysis was also conducted,and the results showed that the PdbHLH57 protein had self-transcription activation.To better explore the functions of the PdbHLH57 protein,two parts of this protein(PdbHLH57-1,PdbHLH57-2)were split to detect their transcriptional activation activity.The results indicated that PdbHLH57-1(1-433aa)had self-transcription activation,and PdbHLH57-2(433-628aa)had no transcription activation.The expression of PdbHLH57 peaked in June during different developmental stages in‘ZSCY’,and it was most highly expressed in the phloem among various tissues.These findings offer a basis for understanding the role of PdbHLH57 in colored-leaf poplar.
基金supported by the the National Natural Science Foundation of China(32071751).
文摘A geomagnetic field is a significant factor dur-ing the growth and development of trees.Changes in the magnetic field(MF)will result in reactions at the biochemi-cal,molecular,cellular and gene levels.However,it is not clear how a magnetic field affects metabolism and home-ostasis under stressful conditions such as salinity.In this study,a novel method was developed of a static magnetic field(SMF)to investigate magnetobiological changes in trees.The results show that pre-treatment of poplar(Popu-lus×euramericana‘Neva’)cuttings with a static magnetic field significantly mitigated the negative effects of salinity stress on their growth and physiological activities.Bio-chemical assays revealed that several chemical messengers,including hydrogen peroxide(H2O2)and O_(2)^(·-),were sig-nificantly improved in roots treated with salt,implying an increase reactive oxygen species.A static magnetic field also significantly increased proline concentrations,soluble protein contents,and CAT and SOD activities.Electrophysiological experiments further revealed that pre-treatment with a static magnetic field remarkably decreased salt-induced Na^(+)influx and H^(+)efflux which control plant salt tolerance.In pharmacological experiments,because the Na^(+)/H^(+)cor-relation was closely related to the SMF-activated plasma membrane and Na^(+)antiporter activity alleviated the mas-sive accumulation of salt-induced reactive oxygen spe-cies(ROS)within the roots.In addition,a static magnetic field dramatically increased the transcriptional activity of stress-responsive genes,including PtrRBOHD and PtrHA5.Together,these results indicate that SMF reduced Na^(+)influx by activating Na^(+)/H^(+)antiporters and plasma membrane H^(+)-ATPase to effectively maintain homeostasis by regu-lating the reactive oxygen species system and cytoplasmic osmotic potential.Ultimately,these static magnetic field methods improved salt tolerance in poplar cuttings,and,for future research,similar methods could be applied to other plants.
基金ThePresidentialFoundationofTheChineseAcademyofSciences NaturalScienceFoundationofHebeiProvince China
文摘Partially modified Bt Cry1Ac gene and the arrowhead proteinase inhibitor (API) gene were used to construct a plant transformation vector pBtiA and this construct was transferred into the genome of the hybrid poplar 741 [ Populus alba L.×( P. davidiana Dode+ P. simonii Carr.)× P. tomentosa Carr.] by Agrobacterium _ mediated transformation. Ten kanamycin resistant plants have been regenerated. Upon insect bioassay using Clostera anachoreta (Fabricius), three of the examined plants were demonstrated to be highly resistant to the testing insects. The mortality of insect larvae on one plant was higher than 90% in 6 days after infestation and the growth of the survival larvae were seriously inhibited. Results of PCR and Southern blot analysis indicated that both Bt Cry1Ac gene and API gene were integrated as a single copy into the genomes of these three plants when Cry1Ac gene fragment was used as the probe. Protein dot blot immunoassay and ELISA analysis revealed that at least the Cry1Ac protein was produced in these three transgenic plants and the expression levels were estimated to be approximately 0.015% of the leaf total soluble protein. This is the first report on insect resistant transgenic hybrid poplar 741 that expresses two insecticidal protein genes.
文摘The cDNA fragment encoding caffeic acid 3_O_methyltransferase (COMT) in Chinese white poplar ( Populus tomentosa Carr.) was isolated and cloned by RT_PCR technique. The size of the cDNA fragment is 1 080 bp, which almost covers the whole cDNA_encoding region. Authors’ cDNA fragment in P. tomentosa shares 98.7% homology with the reported corresponding cDNA in the P. tremuloids at nucleotide level, 99.4% homology at amino acid level, respectively. The analysis of Northern dot hybridization showed that COMT is expressed specifically in the developing secondary xylem of stem during the season of xylem differentiation, which means the linkage between the gene expression for a monolignol biosynthetic enzyme and seasonal regulation of xylem development in woody plant.
基金This work was supported by the National Major Basic Research and Development Program(No.TG1999016004)Jiangsu Provincial Natural Science Foundation(No.BK2003213).
文摘Codon usage is the selective and nonrandom use of synonymous codons to encode amino acids in genes for proteins. The analysis of codon usage may improve the understanding of cocion preferences between different species and allow to rebuild the codons of exogenous genes to increase the expression efficiency of exogenous genes, Here, codon DNA sequence （CDS） of four poplar species, including Populus tremuloides Michx., P. tomentosa Carr., P. deltoides Marsh., and P. trichocarpa Torr. ＆ Gray., is used to analyze the relative frequency of synonymous codon （RFSC）. High-frequency codons are selected by high-frequency （HF） codon analysis. The results indicate that the codon usage is common for all four poplar species and the codon preference is quite similar among the four poplar species. However, CCT encoding for Pro, and ACT coding for Thr are the preferred codons in P. tremuloides and P. tomentosa, whereas CCA coding for Pro, and ACA coding for Thr are preferred in P. deltoides and P. trichocarpa The codons such as TGC coding for Cys, TTC coding for Phe, and AAG coding for Lys, are preferred in the poplar species except P trichocarpa. GAG coding for Glu is preferred only in P deltoides, while the other three poplar species prefer to use GAA. The commonness of preferred codon allows exogenous gene designed by the preferred cocion of one of the different poplar species to be used in other poplar species.
基金This research was supported by National Natural Science Foundation of China (Grant No. 30070616).
文摘The microfibril angle of seven poplar clones was determined by using X-ray diffraction technique. Microfibril angle, wood basic density, fiber length, fiber width and cellulose content were assessed for every growth ring at breast height for all sample trees. Significant variation in microfibril angle was observed among growth rings. Mean microfibril angle (MFA) at breast height varied from 7.8?to 28?between growth rings with cambial age and showed a consistent pith-to-bark trend of decline an-gles. Analysis of variance also indicated that there were significant differences in wood basic density, fiber length, fiber width and cellulose content between the growth rings, which had an increasing tendency from pith to bark. Correlations between MFA and examined wood properties were predominantly large and significant negative (?0.01), and the coefficients were -0.660 for cellulose content, -0.586 for fiber length, -0.516 for fiber width and -0.450 for wood basic density, respectively. Regression analysis with linear and curve estimation indicated that a quadratic function showed the largest R2 and the least standard error for describing the relationships between microfibril angle and measured wood properties, and the correlation coefficients were over -0.45 (n=125). The results from this study suggested that microfibril angle would be a good characteristic for improvement in the future breeding program of poplars.
文摘The leaves of Bt (Bacillus thuringiensis) transgenic poplar (Populus nigra L.) and CpTI (Cowpea trypsin inhibitor) transgenic poplar ((P. tomentosa×P. bolleana)×P. Tomentosa) were taken to feed the 4th-5th-instar larvae of American white moth (Hyphantria cunea (Drury)) for determination of the activities of the protective enzyme system inside larvae’s body. The physiological and biochemical effects of the transgenic poplars on the larvae were studied. The results showed that the two kinds of transgenic poplars had similar effects on the protective enzyme system in the midgut of larvae. The activities of superoxide dismutase, catalase, and peroxidase in midgut of the larvae increased gradually, reached the highest value at a certain time, and then decreased suddenly. For the larvae that were fed with the leaves of Bt transgenic poplar, the peak value of superoxide dismutase and catalase presented at the time of 24-h feeding, while the peak of peroxidase took place at the time of 12-h feeding. The activities of these protective enzymes for the larvae that were fed with leaves of CpTI transgenic poplar peaked 12 h later than that of those fed with leaves of Bt transgenic poplar. The comparison of activities of the protective enzymes was also carried out between the larvae with different levels of intoxication. It was found that the activities of protective enzyme of the seriously intoxicant larvae were higher than that of the lightly intoxicant larvae. This difference was more obvious in the group treated with CpTI transgenic poplar.
基金The study was supported by PPI/PPIC China Program (No. HB-19) and Wetland Laboratory Opening Foundation of Hubei Province (No. HNKFJ20021301).
文摘A study was conducted to evaluate the soil nutrient status of poplar plantation by Soil Nutrient Systematic Approach (SNSA) in Jianghan Plain, Hubei Province, China. Soil physiochemical properties were analyzed in laboratory through collection soil samples of study site. Ten treatments of application different fertilizers were designed such as CK, optimum treatment (N, P, K, Zn), N(P, K, Zn), P(N, K, Zn), K(N, P, Zn), +Mg(N, P, K, Zn, Mg), Zn (N,P,K), +2P(N, 2P, K, Zn), +2K(N, P, 2K, Zn), and 2N+2P+2K(2N, 2P, 2K, Zn) for field experiment to test the effect on tree height, diameter (DBH) growth, and dry weight of poplar. The results showed that there was no significant difference in tree heights between treatments with different fertilizers, diameter growth of poplar trees in treatments of lack of N and Zn was significantly slower than that of trees in optimum treatment, and dry weight of poplar dropped significantly for treatment of CK as well as treatments without application N and Zn. It is concluded that N and Zn were main limiting factor for poplar growth. Results from laboratory analysis and field experiment were uniform per-fectly, which proved that SNSA was reliable in evaluating soil nutrient status of poplar plantation.
文摘Poplars are among the most important deciduous tree species in China. China is replete with natural resources of poplars. Poplars have a number of good characteristics, including fast growth rate, high yield, many uses, easiness of tissue culture and small gene group that make them well suited as a model system for the application of genetic engineering in forest trees. In the last decade, much progress has been made in genetic improvement of poplar species in China. Modern biotechnology is an important tool for genetic improvement in forest trees, and its applications to genetic improvement in poplars, which covers genetic transformation, gene expression, construction of genetic linkage map, QTLs (quantitative trait loci) identification and molecular assisted selection are reviewed in this paper. At the same time, the existing problems and outlook about the application of modern biotechnology to genetic improvement in forest trees are also discussed.
基金Supported by National 948 Project(2011-4-63)Special Research Fund for Welfare Act of State Forestry(200904001-3)Youth Fund of Anhui Normal University(2009xqn73)~~
文摘[Objective]The paper was to study the effect of continuous cropping on leaf nutrient and growth of different species of poplar plantation.[Method] The tree height,diameter at breast height（DBH）,volume of different generations and species of poplar plantation in poplar production area in northern Jiangsu Province,as well as TN,TP and TK content in their leaves were determined through field investigation and indoor experiment.[Result] With the increasing generation,the changes of TN,TP and TK content in the leaves of different ages of two varieties of forest stand were also different.However,with the increasing tree ages,TN,TP and TK contents in leaves showed decrease trend.With the increasing generation,the changes of tree height of I-69 and I-72 poplar showed the similar trend.The effect of increasing generation on tree height of 7-year-old and 10-year-old poplar was relatively stable,showing decrease trend from generation to generation.The tree height of 4-year-old poplar first increased and then decreased with the increasing generation.The changes of DBH along with different generations were basically consistent with the changes of tree height.With the increasing cultivation generations,the volume of 7-year-old and 10-year-old poplar decreased with significant difference.[Conclusion ] The result provided basis for rational fertilization and management of poplar plantation,improvement of productivity of poplar plantation,and achievement of sustainable management of plantation.
基金National Foundation of Ninth Five-Year Plan (No. 96-005-04-01-03).
文摘Through the methods of correlation analysis and main factor analysis, the relationship between the poplar INA bacte-rial canker and circumstances was analyzed and 9 main factors for affecting the disease were selected. Based on the compre-hensive analysis of main factors and induced factors, the standard for risk grades of this disease was promoted and northeast region of China was divided into 4 districts with different risk grades: seriously occurring district, commonly occurring district, occasionally occurring district, and un-occurring district. Nonlinear regression analysis for six model curves showed that the Richard growth model was suitable for describing the temporal dynamics of poplar INA bacterial canker. By stepwise variable selection method, the multi-variable linear regression forecasting equation was set up to predict the next year抯 disease index, and the GM (1,1) model was also set up by grey method to submit middle or long period forecast.
文摘Through five years (1996-2000) experiment, the growth characteristics and resistance to insect and cold of the seven poplar varieties including P. po pularis, P. opera, P. pseudo-simonii, P. beijinensis, P. bolleana, P. ( eurameri cana and P. simonii, which were planted in loess hilly land in northwest Shanxi Province, were tested under different planting densities and site conditions. A randomized block design and three times repetition were adopted in the test. Bas ed on the test results in arid and cold area of the northwest Shanxi, the hybrid poplar trees taking Populus cathaysna as their female parent could be selected for afforestation, such as P. popularis and P. opera, and the growing space of s ingle plant should be larger than 20 m2. P. bolleana as an introduced tree speci es grows well in this area, but its growth is likely affected by ground water co ndition. On the site with relatively abundant soil water, P. bolleana usually su ffer from frost crack at its trunk base. As a result, P. bolleara is suited to p lanting in the site where is short of soil water. P. x euramericana is not suita ble for large-scale afforestation, especially in arid slopes and ridges of loess hilly land .
基金This paper is part of the subject of integrated control of longicorn of poplar for mainly focusing on pest resistance which was supported by Jilin Provincial Forestry Department (96-010).
文摘An experimental area of poplar was established in Songyuan of Jilin Province in 1999 for testing the resistance of different poplar stains to Saperda poplnea. Incidence of S. poplnea on ten poplar strains were investigated, and the main trophic component of branches of these poplar trees were measured and analyzed in April 2001. The results showed that there existed significant difference in population size of S. poplnea on different poplar strains, and the branches of these poplar strains have significant difference in nutrient component and content of amino acids. The population size of this pest had a significantly positive correlation with dissolvable total sugar and water content but had no significant correlation with content of total nitrogen and protein nitrogen.
文摘Poplar is one of the dominant tree species for the establishment of fast growing plantations in Shandong Province. Eighteen poplar clones belonging to Populus aigeiros section were introduced from Italy, Turkey and domestic regions. Populus deltoides cv. 慙ux?I-69/55 (I-69), which was widely used in Shandong Province, China, was taken as control clone (I-69). Following a randomized complete block design, seedling test and controlled afforestation trials were carried out at Juxian County, Caoxian County and Laiyang City. The results showed that the poplar clone (Populus ?euramericana cv. ?02/74?, namely 102/74, performed well both in terms of adaptability and growth rate. The mean height of 13.9 m (H), diameter at breast height of 18.0 cm (DBH) and volume growth of 0.1445 m3 (V) were 2.2 %, 21.6% and 52.9 % higher than those of I-69 (CK), respectively, at the age of 5 years at three experimental sites. Moreover, the clone can be propagated easily and showed high resistance to poplar disease, pest as well as salinity and had longer growing period. Furthermore, wood basic density and fiber length of new poplar clone (102/74) were as same as I-69 (CK). It was concluded that the selected clone (102/74) was ideal for the estab-lishment of fast-growing poplar plantations, especially for the pulpwood plantations in Shandong Province.
文摘The change of microbial community characteristics in the different rhizo- sphere zones of hybrid poplar （Populusdeltoidsxnigra, DN34） under atrazine stress were investigated by rhizo-boxes and Biolog system in a greenhouse experiment, with sublimed sulfur and calcium hydroxide as soil pH regulators. Data from the measurement by the Biolog ECO plate demonstrated that the value of average well color development （AWCD） and the carbon source utilization of soil microorganisms in the treatments with pH regulators were promoter than CK during the initial 30 days; while the results from the 90 days indicated that the activity and the carbon source utilization of soil microbes in acid regulator treatment began to fall down, even lower than that of poplar implant treatment, then the alkaline treatment could still stimulate and promote the activity and the carbon source utilization ability of soil microbes. Overall, the activity and community structure of soil microbes in rhizo- sphere zones of atrazine-contaminated soil did not show steady regularity during the phytoremediation process by using hybrid poplars. For the reason that the Biolog E- CO plate, which only had 31 kinds of carbon sources, could not really indicate the detail information about the function diversity of community structure of soil mi- crobes. So it＇s essential for us to take more sophisticated analysis tools for further study.
文摘Based on the data of stand investigation and stem analysis, the effects of climate factors on the poplar protection forest increment in the riverbank field of the Dalinghe and Xiaolinghe rivers of Liaoning Province, China were studied by step-wise regression procedure and grey system theories and methods. A regression model reflecting the correlation between the height increment of poplar protection forest and climatic factors was developed. The order of grey relevance for the effect of climatic factors on the height increment of poplar protection forest is: light>water>heat, and it could be interpreted that the poplar increment was mainly influenced by light factor, water factor, and heat factor. This result will provide scientific basis for the in-tensive cultivation and regeneration of the poplar protection forest in riverbank field in similar regions in China.
文摘lnoculation experiment .was made for 15 poplar species to determine their resistance to Mirssonina brunneaby the agar leaf-disc techniquc and the water-culture shoots technique The results show that Populus simonii and nigravar. theveslina are very susceptible to the disease:P. davidiana and P.koreana are slightly reslstant to the disease P. us-suriensis has high resistance. and the others remain moderate resistance. Experiments are also made for healthy leaves toanalysis the inorganic element content and water Content. And the results show that the contents of Fe and Ca are remarkblynegativcly related to the resistance of poplars to Marssonina brunnea.
