the investigation was carried out on 10-year-old plantation of Fraxinus mandshurica in Mao抏r Mountain Experimental Station of Northeast Forest University. Tree height (H), diameter at breast height (D1.3) and the inc...the investigation was carried out on 10-year-old plantation of Fraxinus mandshurica in Mao抏r Mountain Experimental Station of Northeast Forest University. Tree height (H), diameter at breast height (D1.3) and the increment of tree height in 5 years (H5), the thickness of humus layer, as well as the soil moisture were measured for the plantation and the growth indexes (H, D1.3, H5) for different site conditions were analyzed. The results showed that main site factors influencing the growth of Fraxinus mandshurica were soil moisture, gradient and location of slope in order. The growth of Fraxinus mandshurica was better on the middle- or up-slope site than on the down-slope site. Soil moisture and late frost caused by terrain are the main reasons that limit the growth of Fraxinus mandshurica plantation.展开更多
The extract of green peel of Juglans mandshurica Maxim was extracted by common method for studying its insecticidal activities and analyzing the active components. Results showed that the alcohol extract and the chlor...The extract of green peel of Juglans mandshurica Maxim was extracted by common method for studying its insecticidal activities and analyzing the active components. Results showed that the alcohol extract and the chloroform part of extract （separated with chloroform from alcohol extract） form green peel of J. mandshurica have insecticidal activities in contact toxicity and stomach toxicity against larvae of Lymantria dispar L.. After application of the extracts for five days, the corrected mortality of larvae of Lymantria dispar for both extracts was more than 50% in contact toxicity and stomach toxicity at the concentration of ≥ 5 g·L^-1. The insecticidal activity for both alcohol extract and chloroform part of extract is more effect in contact toxicity than in stomach toxicity, but no significant difference in the insecticidal activities was found between alcohol extract and chloroform part of extract. The active components in the chloroform part of extract from green peel of.J. mandshurica were analyzed by GC-MS. The analyzed results showed that the active components in the chloroform part of extract are： （1） joglone （5-hydroxy-1,4- naphthaoquinone）, the relative content 27.11%, （2） 1,5-Naphthalenediol, the relative content 9.52%, （3） 7-Methoxy-1-tetralone, the relative content 6.81%, （4） Benzofuran, 2,3-dihydro-, the relative content 6.76%, （5） 4-Hydroxy-2-methoxycinnamaldehyde, the relative content 3.99%, （6） 2-Methoxy-4-vinylphenol, the relative content 3.05%.展开更多
Syringa species not only have good ornamental properties but also play an important role in the landscaping and environmental purification of cities.To investigate the chilling stress resistance of Syringa oblata Lind...Syringa species not only have good ornamental properties but also play an important role in the landscaping and environmental purification of cities.To investigate the chilling stress resistance of Syringa oblata Lindl.and Syringa reticulata var.mandshurica and provide theoretical grounds for the practical cultivation of Syringa species,in vitro leaves were used to study photosynthetic gas exchange parameters and chlorophyll fluorescence parameters.After nine hours of chilling,decreasing rates of net photosynthesis,stomatal conductance,and transpiration in S.reticulata var.mandshurica leaves were significantly greater than that of the S.oblata,while intercellular CO2 concentrations in S.oblata leaves were higher than those in S.reticulata var.mandshurica.The quantum yield of PSII reaction center(APSII)declined in S.reticulata and light capture efficiency(Fv 0/Fm 0)was stable.However,reduction percentages of Fv 0/Fm 0,APSII,and Fv/Fm in S.oblata were significant higher than those of S.reticulata var.mandshurica.After nine hours of chilling,the relative variable fluorescence of VJ and VI of S.oblata increased and the increasing rate of VJ was greater than VI.In contrast,the change of VJ and VI in S.reticulata var.mandshurica leaves was relatively small.This suggests that chilling primarily damaged the electron transport process of QA to QB at the receptor site of the PSII reaction center.Photosynthetic capacity of S.oblata was more sensitive to chilling stress compared to S.reticulate var.mandshurica,which the limitations were mainly due to non-stomatal factors such as the decrease in electron transport efficiency,activity in the PSII reaction center,and the destruction of the photodamage defense system.展开更多
RELATED TO AP2.12(RAP2.12)is one of the Ethylene Response Factors(ERF)transcription factor and plays a key role in controlling plant root bending and responding to multiple abiotic stresses including hypoxia stress.In...RELATED TO AP2.12(RAP2.12)is one of the Ethylene Response Factors(ERF)transcription factor and plays a key role in controlling plant root bending and responding to multiple abiotic stresses including hypoxia stress.In this study,FmRAP2.12 gene was isolated and characterized from Fraxinus mandshurica Rupr.The open reading frame(ORF)of FmRAP2.12 was 1170 bp and encoded a protein of 389 amino acids.The conserved domains,three-dimensional phylogenetic relationship of FmRAP2.12 was also investigated.Quantitative real-time(qRT-PCR)analyzed the expression of FmRAP2.12 in different tissues.The expression level of FmRAP2.12 was highest in roots followed by leaves,and lowest in male flowers.Abiotic stress and hormone signal-induced expression was established using qRT-PCR.Salt stress induced FmRAP2.12 to a double peak pattern:the first peak value was at 6 h and the second at 72 h.Drought stress also induced FmRAP2.12 to a double peak pattern:the first at6 h and the second at 48 h.FmRAP2.12 was up-regulated after initiation of gibberellic acid(GA3)treatment,with a one peak pattern at 24 h.FmRAP2.12 may not respond to cold stress and Abscisic acid(ABA)treatment.The transient overexpression of FmRAP2.12 caused the up-expression of downstream key genes of abiotic stress response and gibberellin pathway.Our research reveals the molecular characteristic and expression patterns under abiotic stress and hormone condition of FmRAP2.12,providing support for the genetic improvement of F.mandshurica at a molecular level.展开更多
Nutrient retranslocation in trees is important in nutrient budgets and energy flows in forest ecosystems. We investigated nutrient retranslocation in the fine roots of a Manchurian Ash （Fraxinus mandshurica） and a L...Nutrient retranslocation in trees is important in nutrient budgets and energy flows in forest ecosystems. We investigated nutrient retranslocation in the fine roots of a Manchurian Ash （Fraxinus mandshurica） and a Larch （Larix olgensis） plantation in northeastern China. Nutrient retranslocation in the fine roots was investigated using three methods, specifically, nutrient concentration, the ratio of Ca to other elements （Ca/other elements ratio） and nutrient content. The method based on nutrient content proved most suitable when investigating nutrient retranslocation from fine roots of the two species. The nutrient-content-based method showed that there were retranslocations of N, P, K and Mg from the fine roots of Manchurian Ash, with retranslocation efficiencies of 13, 25, 65, and 38 %, respectively, whereas there were no Ca retranslocations. There were retranslocations of N, P, K, Ca and Mg from the fine roots of Larch, with retranslocation efficiencies of 31, 40, 52, 23 and 25 %, respectively.展开更多
Fine roots are important in root absorption of nutrient and water,and in root turnover.Accurate definition of fine roots is a prerequisite to improved estimation of the physiological and ecological functions of forest...Fine roots are important in root absorption of nutrient and water,and in root turnover.Accurate definition of fine roots is a prerequisite to improved estimation of the physiological and ecological functions of forest ecosystems.Root development and physiological functions are reflections of root anatomical structure.In this study,the anatomical structures of different root orders were analyzed by examining paraffin sections of one-year old Fraxinus mandshurica seedlings.One-year-old F.mandshurica seedlings had over five root orders.The root anatomical structures of all orders showed more differences.First and second order roots consisted of four sections： the epidermis,cortex,pericycle,and vascular bundles.Fourth and fifth order roots were mainly composed of the skin and peripheral vascular bundles（including the xylem and phloem）.Third order roots had root epidermal and cortical structures,but the quantity and integrity of the cortical cells were inferior to those of the first and second order roots,and superior to those of the fourth and fifth order roots.All the first and second order roots and some third order roots with discontinuous cork layer（〈0.4 mm in diameter）,but not the fourth and fifth order roots,were the fine roots of one-year old F.mandshurica seedlings.Although they had similar diameters,different portions of root systems had different anatomical structures and therefore,vary in capacity to absorb water and nutrients.Fine roots were accurately defined by root diameter,branch orders,and anatomical structural features of one-year old F.mandshurica seedlings.展开更多
Somatic embryogenesis of Fraxinus mandshurica has the problems of low somatic embryo(SE) yield,unsynchronized SE development,and a high percentage of deformed SEs.We aimed to improve F.mandshurica SE production by syn...Somatic embryogenesis of Fraxinus mandshurica has the problems of low somatic embryo(SE) yield,unsynchronized SE development,and a high percentage of deformed SEs.We aimed to improve F.mandshurica SE production by synchronizing SE development,improving SE quality,and inducing root formation to obtain complete regenerated plants.Cotyledons of immature zygotic embryos of F.mandshurica were induced to form callus and then SEs.The SE induction percentage from explants differed among 32 mother trees,and the one with the highest SE induction percentage(29.8%) was used for further experiments.The highest callus induction percentage was94.2% on 1/2-strength Murashige and Skoog medium(MS1/2)supplemented with 0.15 mg·L^(-1) naphthalene acetic acid.The highest callus proliferation coefficient(240.5) was obtained on McCown's Woody Plant Medium containing 0.1 mg·L^(-1)6-benzyl adenine and 0.15 mg·L^(-1) 2,4-dichlorophenoxyacetic acid.The highest number of SEs(1020.5 g~(-1) fresh weight) was obtained on MS1/2 medium supplemented with1 mg·L^(-1) 6-benzyladenine.The highest number of cotyledon embryos(397/g fresh weight) was obtained by incubating materials on medium containing 1 mg·L^(-1) abscisic acid and then applying a drying treatment.The cotyledon embryos were milky white,uniformly sized(average length 4.7 mm),and 80% of them were normal.The SE rooting percentage on 1/2 MS medium containing 0.01 mg·L^(-1) NAA was 37.5%.Overall,the germination percentage of SEs was 26.4%,and complete regenerated plants were obtained after transplanting and acclimation.These results provide more possibilities for the preservation and breeding of F.mandshurica.展开更多
To determine light requirement and adaptability of Fraxinus mandshurica seedlings, the seasonal variations of photosynthetic variables were measured in 3-year-old seedlings grown under four light levels （100%, 60%, 3...To determine light requirement and adaptability of Fraxinus mandshurica seedlings, the seasonal variations of photosynthetic variables were measured in 3-year-old seedlings grown under four light levels （100%, 60%, 30%, and 15% of full sunlight） with a LI-6400 portable photosynthesis system. The leaf chlorophyll content, special leaf weight, annual height and basal diameter increment of seedlings were also observed. The maximum and minimum values of net photosynthetic rate, maximum rate of carboxylation, and maximum rate of electron transport of F. mandshurica seedlings were detected with 60% and 15% of full sunlight treatments, respectively. With the decrease of light level, both light saturation point and special leaf weight significantly declined （p 0.05）, but leaf chlorophyll content significantly increased （p 0.05）. Annual height and basal diameter increments of seedlings grown under 60% of full sunlight treatment were significantly greater than those of seedlings under other treatments （p 0.05）. It was concluded that F. mandshurica seedlings can adapt to a wide range of light environments from 15% to 100% of full sunlight by adjusting light saturation point, leaf chlorophyll content and special leaf weight. According to the maximum of relative growth, 60% of full sunlight treatment is the optimum light level for the growth of 3-year-old F. mandshurica seedlings.展开更多
The data of provenance trial on Juglans mandshurica young tree were investigated and studied from different provenance. Analysis methods of variance and correlation analysis were used to analyze these data. The follow...The data of provenance trial on Juglans mandshurica young tree were investigated and studied from different provenance. Analysis methods of variance and correlation analysis were used to analyze these data. The following conclusions were obtainedf (1) The difference of growth characters of Juglans mandshurica is relatively significant among provenances, (2) The result of first trial has indicated that Julans mandshurica growth trend expresses two-way gradual change trend with different longitude and latitude, but the second trial has no obvious gradual change trend. Height of Juglans mandshurica is negatively correlated with elevation; (3) The provenance of Shulan. Mao'ershan and Baishishan were selected as superior provenance of afforestational seeds for Mao'ershan and its brink region.展开更多
Osmotic stress promotes somatic embryogenesis of Fraxinus mandshurica,which leads to accumulation of reactive oxygen species(ROS).The single pieces of cotyledons of F.mandshurica were used as explants to induce somati...Osmotic stress promotes somatic embryogenesis of Fraxinus mandshurica,which leads to accumulation of reactive oxygen species(ROS).The single pieces of cotyledons of F.mandshurica were used as explants to induce somatic embryogenesis in osmotic-stress medium.Furthermore,the hydrogen peroxide H_(2)O_(2) content of explanted cells was varied by adding exogenous H_(2)O_(2) or catalase solution to assess the effects of the exogenous H_(2)O_(2)on somatic embryogenesis,intracellular H_(2)O_(2)accumulation,and the relationship between signaling mediated by ROS or reactive nitrogen species.The results revealed that exogenous H_(2)O_(2)(100?300μmol L^(–1))increased the number of somatic embryos.On 60th day of exogenous H_(2)O_(2)(200μmol L^(–1))treatment,the number of somatic embryos of explants treated,which was 136.54%,was higher than the control.Moreover,exogenous H_(2)O_(2)(100μmol L^(–1))significantly increased the intracellular H_(2)O_(2)content and enhanced the activities of superoxidase dismutase and peroxidase.Finally,exogenous H_(2)O_(2)(100μmol L^(–1))activated the intracellular non-enzymatic pathway for nitric oxide(NO)synthesis.The somatic embryogenesis in broadleaf trees increases with the change of endogenic ROS content,and depends on the upregulation of antioxidant enzymes.Both H_(2)O_(2)and NO,as signaling molecules,were found to be involved in the process of somatic embryogenesis in broadleaf trees.In the process of exogenous H_(2)O_(2)promoting somatic embryogenesis,NO synthesis depended on non-enzymatic reactions.These results provide a scientific basis for resolving the mechanism by which ROS levels are regulated during somatic embryogenesis of broadleaf trees and establish a reasonable and efficient technology system for regulating somatic embryogenesis of trees.展开更多
Bioassay and GC-MS determination indicated that inhibitors of seeds of Fraxinus mandshurica Rupr were distributed mainly in zones of β-inhibitors (including ABA) and of high and low Rf value. The inhibitory activity ...Bioassay and GC-MS determination indicated that inhibitors of seeds of Fraxinus mandshurica Rupr were distributed mainly in zones of β-inhibitors (including ABA) and of high and low Rf value. The inhibitory activity of outer seed coat of the dormant seed (control treatment) was higher than that of seeds with only the inner coat attached e.g. ABA was 114 and 54ng/g fresh weight respectively. The inhibitory effect of No. 12 zone was even higher than ABA. The inhibitory activity of all the zones decreased after stratification (St) and burying (AO) treatment, especially that of the outer seed coat, whose ABA content decreased to 7(St) and 11(AO) ng / g(fw). However, the decrease in inhibition of root growth lagged bchind'thc decrease in germination. It is concluded that burial is advantageous to regeneration. Inhibitors of the outer seed coat and seeds were mostly destroyed under the adverse conditions of natural dissemination (Di treatment) indicating that Di was not conducive to regeneration. MS analysis revealed that the largest peaks of No. 6, 7 and 12 zones were linoleic acid, olcic acid and 17-C, 18-C, and 20-C long chain fatty acids. Several coumarins were found in No. 6 and 7 zones, and cadincncs, farncsol and scsquitcrpcncs were found in No. 6 and 12 zones having common bioorigins with ABA.展开更多
Fraxinus mandshurica Rupr.is one of the main afforestation species in northeast China,and there is great demand for improved F.mandshurica varieties.The results of an investigation into and analysis of the growth trai...Fraxinus mandshurica Rupr.is one of the main afforestation species in northeast China,and there is great demand for improved F.mandshurica varieties.The results of an investigation into and analysis of the growth traits of F.mandshurica provenances and families showed that there were significant differences in different periods.However,variations in growth traits decreased year by year.There was a significant negative correlation between tree heights of the provenances and sunshine hours in their areas of origin.The provenances of Xinglong,Hailin and Wuchang were selected based on the volume of 18-year-old trees.The average genetic gain from the selection of fast-growing provenances was 19.4%.Ten superior fast-growing families were selected.The average volume of the selected families was22.6%,higher than that of all families.The correlation coefficient between heights at 6-year-old and at 18a was 0.838for provenances,and between heights at 4-year-old and at 18-year-old was 0.303 for families.These results indicate that early selection for height in provenances or families could be performed at 6 years or 4 years,respectively.Early selection for DBH and volume in families could start at 8 years.展开更多
文摘the investigation was carried out on 10-year-old plantation of Fraxinus mandshurica in Mao抏r Mountain Experimental Station of Northeast Forest University. Tree height (H), diameter at breast height (D1.3) and the increment of tree height in 5 years (H5), the thickness of humus layer, as well as the soil moisture were measured for the plantation and the growth indexes (H, D1.3, H5) for different site conditions were analyzed. The results showed that main site factors influencing the growth of Fraxinus mandshurica were soil moisture, gradient and location of slope in order. The growth of Fraxinus mandshurica was better on the middle- or up-slope site than on the down-slope site. Soil moisture and late frost caused by terrain are the main reasons that limit the growth of Fraxinus mandshurica plantation.
基金This study was supported by Heilongjiang Natural Science Foundation (C2004-28)
文摘The extract of green peel of Juglans mandshurica Maxim was extracted by common method for studying its insecticidal activities and analyzing the active components. Results showed that the alcohol extract and the chloroform part of extract （separated with chloroform from alcohol extract） form green peel of J. mandshurica have insecticidal activities in contact toxicity and stomach toxicity against larvae of Lymantria dispar L.. After application of the extracts for five days, the corrected mortality of larvae of Lymantria dispar for both extracts was more than 50% in contact toxicity and stomach toxicity at the concentration of ≥ 5 g·L^-1. The insecticidal activity for both alcohol extract and chloroform part of extract is more effect in contact toxicity than in stomach toxicity, but no significant difference in the insecticidal activities was found between alcohol extract and chloroform part of extract. The active components in the chloroform part of extract from green peel of.J. mandshurica were analyzed by GC-MS. The analyzed results showed that the active components in the chloroform part of extract are： （1） joglone （5-hydroxy-1,4- naphthaoquinone）, the relative content 27.11%, （2） 1,5-Naphthalenediol, the relative content 9.52%, （3） 7-Methoxy-1-tetralone, the relative content 6.81%, （4） Benzofuran, 2,3-dihydro-, the relative content 6.76%, （5） 4-Hydroxy-2-methoxycinnamaldehyde, the relative content 3.99%, （6） 2-Methoxy-4-vinylphenol, the relative content 3.05%.
文摘Syringa species not only have good ornamental properties but also play an important role in the landscaping and environmental purification of cities.To investigate the chilling stress resistance of Syringa oblata Lindl.and Syringa reticulata var.mandshurica and provide theoretical grounds for the practical cultivation of Syringa species,in vitro leaves were used to study photosynthetic gas exchange parameters and chlorophyll fluorescence parameters.After nine hours of chilling,decreasing rates of net photosynthesis,stomatal conductance,and transpiration in S.reticulata var.mandshurica leaves were significantly greater than that of the S.oblata,while intercellular CO2 concentrations in S.oblata leaves were higher than those in S.reticulata var.mandshurica.The quantum yield of PSII reaction center(APSII)declined in S.reticulata and light capture efficiency(Fv 0/Fm 0)was stable.However,reduction percentages of Fv 0/Fm 0,APSII,and Fv/Fm in S.oblata were significant higher than those of S.reticulata var.mandshurica.After nine hours of chilling,the relative variable fluorescence of VJ and VI of S.oblata increased and the increasing rate of VJ was greater than VI.In contrast,the change of VJ and VI in S.reticulata var.mandshurica leaves was relatively small.This suggests that chilling primarily damaged the electron transport process of QA to QB at the receptor site of the PSII reaction center.Photosynthetic capacity of S.oblata was more sensitive to chilling stress compared to S.reticulate var.mandshurica,which the limitations were mainly due to non-stomatal factors such as the decrease in electron transport efficiency,activity in the PSII reaction center,and the destruction of the photodamage defense system.
基金supported by the National Key Research and Development Project of China(No.2017YFD0600605-01)the National Natural Science Foundation of China(NSFC)(No.31270697)
文摘RELATED TO AP2.12(RAP2.12)is one of the Ethylene Response Factors(ERF)transcription factor and plays a key role in controlling plant root bending and responding to multiple abiotic stresses including hypoxia stress.In this study,FmRAP2.12 gene was isolated and characterized from Fraxinus mandshurica Rupr.The open reading frame(ORF)of FmRAP2.12 was 1170 bp and encoded a protein of 389 amino acids.The conserved domains,three-dimensional phylogenetic relationship of FmRAP2.12 was also investigated.Quantitative real-time(qRT-PCR)analyzed the expression of FmRAP2.12 in different tissues.The expression level of FmRAP2.12 was highest in roots followed by leaves,and lowest in male flowers.Abiotic stress and hormone signal-induced expression was established using qRT-PCR.Salt stress induced FmRAP2.12 to a double peak pattern:the first peak value was at 6 h and the second at 72 h.Drought stress also induced FmRAP2.12 to a double peak pattern:the first at6 h and the second at 48 h.FmRAP2.12 was up-regulated after initiation of gibberellic acid(GA3)treatment,with a one peak pattern at 24 h.FmRAP2.12 may not respond to cold stress and Abscisic acid(ABA)treatment.The transient overexpression of FmRAP2.12 caused the up-expression of downstream key genes of abiotic stress response and gibberellin pathway.Our research reveals the molecular characteristic and expression patterns under abiotic stress and hormone condition of FmRAP2.12,providing support for the genetic improvement of F.mandshurica at a molecular level.
基金supported by the National Key Technology Research and Development Program(2012BAD21B0202-02)the Natural Science Foundation of Heilongjiang Province of China(C201340)the assisted project by Heilong Jiang Postdoctoral Funds for Scientific Research Initiation(LBH-Q13006)
文摘Nutrient retranslocation in trees is important in nutrient budgets and energy flows in forest ecosystems. We investigated nutrient retranslocation in the fine roots of a Manchurian Ash （Fraxinus mandshurica） and a Larch （Larix olgensis） plantation in northeastern China. Nutrient retranslocation in the fine roots was investigated using three methods, specifically, nutrient concentration, the ratio of Ca to other elements （Ca/other elements ratio） and nutrient content. The method based on nutrient content proved most suitable when investigating nutrient retranslocation from fine roots of the two species. The nutrient-content-based method showed that there were retranslocations of N, P, K and Mg from the fine roots of Manchurian Ash, with retranslocation efficiencies of 13, 25, 65, and 38 %, respectively, whereas there were no Ca retranslocations. There were retranslocations of N, P, K, Ca and Mg from the fine roots of Larch, with retranslocation efficiencies of 31, 40, 52, 23 and 25 %, respectively.
基金supported by National Key Research and Development Program of China(2017YFD0600605)
文摘Fine roots are important in root absorption of nutrient and water,and in root turnover.Accurate definition of fine roots is a prerequisite to improved estimation of the physiological and ecological functions of forest ecosystems.Root development and physiological functions are reflections of root anatomical structure.In this study,the anatomical structures of different root orders were analyzed by examining paraffin sections of one-year old Fraxinus mandshurica seedlings.One-year-old F.mandshurica seedlings had over five root orders.The root anatomical structures of all orders showed more differences.First and second order roots consisted of four sections： the epidermis,cortex,pericycle,and vascular bundles.Fourth and fifth order roots were mainly composed of the skin and peripheral vascular bundles（including the xylem and phloem）.Third order roots had root epidermal and cortical structures,but the quantity and integrity of the cortical cells were inferior to those of the first and second order roots,and superior to those of the fourth and fifth order roots.All the first and second order roots and some third order roots with discontinuous cork layer（〈0.4 mm in diameter）,but not the fourth and fifth order roots,were the fine roots of one-year old F.mandshurica seedlings.Although they had similar diameters,different portions of root systems had different anatomical structures and therefore,vary in capacity to absorb water and nutrients.Fine roots were accurately defined by root diameter,branch orders,and anatomical structural features of one-year old F.mandshurica seedlings.
基金supported by the Fundamental Research Funds for the Central Universities of China(2572018BW02)the National Natural Science Foundation of China (31400535 and 31570596)+1 种基金the Innovation Project of State Key Laboratory of Tree Genetics and Breeding (2016C01)the National Key R&D Program of China (2017YFD0600600)。
文摘Somatic embryogenesis of Fraxinus mandshurica has the problems of low somatic embryo(SE) yield,unsynchronized SE development,and a high percentage of deformed SEs.We aimed to improve F.mandshurica SE production by synchronizing SE development,improving SE quality,and inducing root formation to obtain complete regenerated plants.Cotyledons of immature zygotic embryos of F.mandshurica were induced to form callus and then SEs.The SE induction percentage from explants differed among 32 mother trees,and the one with the highest SE induction percentage(29.8%) was used for further experiments.The highest callus induction percentage was94.2% on 1/2-strength Murashige and Skoog medium(MS1/2)supplemented with 0.15 mg·L^(-1) naphthalene acetic acid.The highest callus proliferation coefficient(240.5) was obtained on McCown's Woody Plant Medium containing 0.1 mg·L^(-1)6-benzyl adenine and 0.15 mg·L^(-1) 2,4-dichlorophenoxyacetic acid.The highest number of SEs(1020.5 g~(-1) fresh weight) was obtained on MS1/2 medium supplemented with1 mg·L^(-1) 6-benzyladenine.The highest number of cotyledon embryos(397/g fresh weight) was obtained by incubating materials on medium containing 1 mg·L^(-1) abscisic acid and then applying a drying treatment.The cotyledon embryos were milky white,uniformly sized(average length 4.7 mm),and 80% of them were normal.The SE rooting percentage on 1/2 MS medium containing 0.01 mg·L^(-1) NAA was 37.5%.Overall,the germination percentage of SEs was 26.4%,and complete regenerated plants were obtained after transplanting and acclimation.These results provide more possibilities for the preservation and breeding of F.mandshurica.
基金supported by National Nature Science Foundation of China (30830085)
文摘To determine light requirement and adaptability of Fraxinus mandshurica seedlings, the seasonal variations of photosynthetic variables were measured in 3-year-old seedlings grown under four light levels （100%, 60%, 30%, and 15% of full sunlight） with a LI-6400 portable photosynthesis system. The leaf chlorophyll content, special leaf weight, annual height and basal diameter increment of seedlings were also observed. The maximum and minimum values of net photosynthetic rate, maximum rate of carboxylation, and maximum rate of electron transport of F. mandshurica seedlings were detected with 60% and 15% of full sunlight treatments, respectively. With the decrease of light level, both light saturation point and special leaf weight significantly declined （p 0.05）, but leaf chlorophyll content significantly increased （p 0.05）. Annual height and basal diameter increments of seedlings grown under 60% of full sunlight treatment were significantly greater than those of seedlings under other treatments （p 0.05）. It was concluded that F. mandshurica seedlings can adapt to a wide range of light environments from 15% to 100% of full sunlight by adjusting light saturation point, leaf chlorophyll content and special leaf weight. According to the maximum of relative growth, 60% of full sunlight treatment is the optimum light level for the growth of 3-year-old F. mandshurica seedlings.
文摘The data of provenance trial on Juglans mandshurica young tree were investigated and studied from different provenance. Analysis methods of variance and correlation analysis were used to analyze these data. The following conclusions were obtainedf (1) The difference of growth characters of Juglans mandshurica is relatively significant among provenances, (2) The result of first trial has indicated that Julans mandshurica growth trend expresses two-way gradual change trend with different longitude and latitude, but the second trial has no obvious gradual change trend. Height of Juglans mandshurica is negatively correlated with elevation; (3) The provenance of Shulan. Mao'ershan and Baishishan were selected as superior provenance of afforestational seeds for Mao'ershan and its brink region.
基金supported by the National Natural Science Foundation of China(31570596 and 31400535)the Fundamental Research Funds for the Central Universities(2572018BW02)+1 种基金the Innovation Project of State Key Laboratory of Tree Genetics and Breeding(Northeast Forestry University,2016C01)the National Key R&D Program of China(2017YFD0600600)。
文摘Osmotic stress promotes somatic embryogenesis of Fraxinus mandshurica,which leads to accumulation of reactive oxygen species(ROS).The single pieces of cotyledons of F.mandshurica were used as explants to induce somatic embryogenesis in osmotic-stress medium.Furthermore,the hydrogen peroxide H_(2)O_(2) content of explanted cells was varied by adding exogenous H_(2)O_(2) or catalase solution to assess the effects of the exogenous H_(2)O_(2)on somatic embryogenesis,intracellular H_(2)O_(2)accumulation,and the relationship between signaling mediated by ROS or reactive nitrogen species.The results revealed that exogenous H_(2)O_(2)(100?300μmol L^(–1))increased the number of somatic embryos.On 60th day of exogenous H_(2)O_(2)(200μmol L^(–1))treatment,the number of somatic embryos of explants treated,which was 136.54%,was higher than the control.Moreover,exogenous H_(2)O_(2)(100μmol L^(–1))significantly increased the intracellular H_(2)O_(2)content and enhanced the activities of superoxidase dismutase and peroxidase.Finally,exogenous H_(2)O_(2)(100μmol L^(–1))activated the intracellular non-enzymatic pathway for nitric oxide(NO)synthesis.The somatic embryogenesis in broadleaf trees increases with the change of endogenic ROS content,and depends on the upregulation of antioxidant enzymes.Both H_(2)O_(2)and NO,as signaling molecules,were found to be involved in the process of somatic embryogenesis in broadleaf trees.In the process of exogenous H_(2)O_(2)promoting somatic embryogenesis,NO synthesis depended on non-enzymatic reactions.These results provide a scientific basis for resolving the mechanism by which ROS levels are regulated during somatic embryogenesis of broadleaf trees and establish a reasonable and efficient technology system for regulating somatic embryogenesis of trees.
文摘Bioassay and GC-MS determination indicated that inhibitors of seeds of Fraxinus mandshurica Rupr were distributed mainly in zones of β-inhibitors (including ABA) and of high and low Rf value. The inhibitory activity of outer seed coat of the dormant seed (control treatment) was higher than that of seeds with only the inner coat attached e.g. ABA was 114 and 54ng/g fresh weight respectively. The inhibitory effect of No. 12 zone was even higher than ABA. The inhibitory activity of all the zones decreased after stratification (St) and burying (AO) treatment, especially that of the outer seed coat, whose ABA content decreased to 7(St) and 11(AO) ng / g(fw). However, the decrease in inhibition of root growth lagged bchind'thc decrease in germination. It is concluded that burial is advantageous to regeneration. Inhibitors of the outer seed coat and seeds were mostly destroyed under the adverse conditions of natural dissemination (Di treatment) indicating that Di was not conducive to regeneration. MS analysis revealed that the largest peaks of No. 6, 7 and 12 zones were linoleic acid, olcic acid and 17-C, 18-C, and 20-C long chain fatty acids. Several coumarins were found in No. 6 and 7 zones, and cadincncs, farncsol and scsquitcrpcncs were found in No. 6 and 12 zones having common bioorigins with ABA.
基金Promotion project of State Forestry Administration(2017)06,China。
文摘Fraxinus mandshurica Rupr.is one of the main afforestation species in northeast China,and there is great demand for improved F.mandshurica varieties.The results of an investigation into and analysis of the growth traits of F.mandshurica provenances and families showed that there were significant differences in different periods.However,variations in growth traits decreased year by year.There was a significant negative correlation between tree heights of the provenances and sunshine hours in their areas of origin.The provenances of Xinglong,Hailin and Wuchang were selected based on the volume of 18-year-old trees.The average genetic gain from the selection of fast-growing provenances was 19.4%.Ten superior fast-growing families were selected.The average volume of the selected families was22.6%,higher than that of all families.The correlation coefficient between heights at 6-year-old and at 18a was 0.838for provenances,and between heights at 4-year-old and at 18-year-old was 0.303 for families.These results indicate that early selection for height in provenances or families could be performed at 6 years or 4 years,respectively.Early selection for DBH and volume in families could start at 8 years.
