The stimulative effect of trace elements on seed germination and seedling growth of Pinus tabulaeformis was tested. The experiments were carried out on seed soak and topdressing with different trace elements and varie...The stimulative effect of trace elements on seed germination and seedling growth of Pinus tabulaeformis was tested. The experiments were carried out on seed soak and topdressing with different trace elements and varied concentrations at the nursery of Gardens Research Institute, Harbin, in 2000-2001. The experimental results showed that soaking seed with 1% and 0.2% concentrations of Mn element produced best result for seed germination, and the germination rate was increased by 9%~19% for the seeds treated with 1% concentration and 12%~14% for the seeds treated with 0.2% concentration compared with the control group. The seeds treated with boron element had lowest germination rate. For trace element topdressing, Mn and Mo elements presented good result for seedling growth and the treatment with low concentration was even better. The height or chlorophyll content of the seedlings with spray of low-concentration Mn and Mo element was much higher than that of untreated ones. In the contrast to the treating method of seed soak, topdressing (application of spraying on foliage) had evident effect on seedling growth.展开更多
In an earlier report the ultrastructure and nucleoid organelles of male gamete in Pinus tabulaeformis Carr. have been described. Presently, the ultrastructure of the cytoplasm of the egg cell and pollen tube—imm...In an earlier report the ultrastructure and nucleoid organelles of male gamete in Pinus tabulaeformis Carr. have been described. Presently, the ultrastructure of the cytoplasm of the egg cell and pollen tube—immediately before fertilization and during cytoplasmic transmission of male gametophyte—has been described for the same species. The fate of parental plastids and mitochondria in the proembryo has also been followed. The mature egg cell contains a large amount of mitochondria, but seems to lack normal plastids. Most plastids have transformed into large inclusions. Apart from the large inclusions, there are abundant small inclusions and other organelles in the egg cell. During fertilization, pollen tube penetrates into the egg cell at the micropylar end and thereafter the contents are released. Plastid and mitochondrion of male origin are lacking near the fusing sperm_egg nuclei. The second sperm nucleus—not involved in karyogamy—remains at a site near the receptive vacuole. This nucleus is surrounded by large amount of male cytoplasm containing mixed organelles from the sperm cell, tube cell, and egg cell. At the free nuclear proembryo stage, organelles of male and female origin are visible in the perinucleus_cytoplasmic zone. Most of the mitochondria have the same morphological features as those in the egg cell. Some of the mitochondria appear to have originated from the sperm and tube cells. Plastids are most likely of male gametophyte origin because they have similar appearance as those of the sperm and tube cell. Large inclusions in the egg cell become vacuole_like. Paternal plastids have been incorporated into the neocytoplasm of the proembryo. In the cellular proembryo, maternal mitochondria are more abundant. Plastids resembling those of the sperm and tube cell are still present. These cytological results clearly show that in P. tabulaeformis, plastids are inherited paternally and mitochondria bipaternally. The cytological mechanism of plastid and mitochondrion inheritance in gymnosperm is discussed.展开更多
The cytological mechanism of plastid and mitochondrion inheritance in Pinus is an interesting research topic with only a limited number of published articles. The results indicate that the sperms of Pinus tabu...The cytological mechanism of plastid and mitochondrion inheritance in Pinus is an interesting research topic with only a limited number of published articles. The results indicate that the sperms of Pinus tabulaeformis Carr. contain abundant plastids, mitochondria and organelle DNA. These data provide reliable cytological evidence of paternal plastid and mitochondrion inheritance in Pinus . The results are in line with the confirmed general rule of paternal plastid inheritance in Pinaceae. But whether mitochondria in sperm cells can be transmitted into the embryos is an issue needs further developmental studies. Another important finding is that contrary to earlier classification of the male gamete of Pinaceae into the male nuclei type, the results reveal that male gametes in Pinus tabulaeformis are actually cells. However, the sperm cells are only surrounded by plasma membranes without cell walls. The larger leading sperm cell in a pollen tube section is long in shape, with a large amount of cytoplasm; while the second sperm cell is smaller, round in shape and contains less cytoplasm. Whether this feature of the male gamete type could be considered as a representative characteristic of the family is discussed and further conclusions await more experimental evidences from studies on plants from different species.展开更多
Although carbon(C), nitrogen(N), and phosphorous(P) stoichiometric ratios are considered good indicators of nutrient excess/limitation and thus of ecosystem health, few reports have discussed the trends and the recipr...Although carbon(C), nitrogen(N), and phosphorous(P) stoichiometric ratios are considered good indicators of nutrient excess/limitation and thus of ecosystem health, few reports have discussed the trends and the reciprocal effects of C:N:P stoichiometry in plant–litter–soil systems. The present study analyzed C:N:P ratios in four age groups of Chinese pine, Pinus tabulaeformis Carr., forests in Shanxi Province, China: plantation young forests(AY,<20 year-old); plantation middle-aged forests(AM, 21–30 year-old); natural young forests(NY,<30 year-old); and natural middle-aged forests(NM,31–50 year-old). The average C:N:P ratios calculated for tree, shrub, and herbaceous leaves, litter, and soil(0–100 cm) were generally higher in NY followed by NM,AM, and AY. C:N and C:P ratios were higher in litter than in leaves and soils, and reached higher values in the litter and leaves of young forests than in middle-aged forests;however, C:N and C:P ratios were higher in soils of middle-aged forests than in young forests. N:P ratios were higher in leaves than in litter and soils regardless of stand age; the consistent N:P<14 values found in all forests indicated N limitations. With plant leaves, C:P ratios were highest in trees, followed by herbs and shrubs, indicating a higher efficiency in tree leaf formation. C:N ratios decreased with increasing soil depth, whereas there was no trend for C:P and N:P ratios. C:N:P stoichiometry of forest foliage did not exhibit a consistent variation according to stand age. Research on the relationships between N:P, and P, N nutrient limits and the characteristics of vegetation nutrient adaptation need to be continued.展开更多
[Objective] This study aimed to investigate the optimal technological condi- tions for ultrasouqd-assisted extraction of polysaccharides from Pinus tabulaeformis seed shells. [Melhod] Polysaccharides were extracted fr...[Objective] This study aimed to investigate the optimal technological condi- tions for ultrasouqd-assisted extraction of polysaccharides from Pinus tabulaeformis seed shells. [Melhod] Polysaccharides were extracted from P. tabulaeformis seed shells by ultrasound-assisted hot water extraction method and detected by phenol- concentrated sulfuric acid method. The effect of extraction temperature, extraction duration, solid-liquid ratio and extraction frequency on the extraction of polysaccha- rides was investigated using single-factor gradient experiment and the extraction conditions for polysaccharides from P. tabulaeformis seed shells were optimized us- ing L9（34） orthogonal design. [Result] The content of polysaccharides extracted twice at 60 ℃ for 25 min with solid-liquid ratio of 1：3.5 reached the maximum. The re- covery rate （n=-5） ranged from 97.71% to 100.67% and RSD was 1.56%, suggesting high stability. [Conclusion] A simple and efficient method for ultrasound-assisted ex- traction of polysaccharides from P. tabulaeformis seed shells was established in this study, which laid solid foundation for the development and utilization of abandoned pine nut shell resources.展开更多
The Qinling Mountains is not only the geographical boundary between North and South China,but also the boundary between subtropical and warm temperate zones.It plays an important role in the geo-ecological pattern of ...The Qinling Mountains is not only the geographical boundary between North and South China,but also the boundary between subtropical and warm temperate zones.It plays an important role in the geo-ecological pattern of China.However,there is controversy about the specific location of this geographical boundary in academic community due to the complexity,transition and heterogeneity of the transitional zone,as well as the differences in the delimitation indicators and research purposes.To further reveal the characteristics of the North-South transitional zone and clarify the specific location of the geo-ecological boundary between North and South China,combined with SRTM topographic data,temperature and precipitation data,Pinus massoniana forest and Pinus tabulaeformis forest,which represent subtropical coniferous forest in South China and temperate coniferous forest in North China respectively,were chosen to analyze their spatial distributions in the Qinling-Daba Mountains and the climatic conditions at their boundary with the climatic indexes of annual precipitation,the coldest month(January) average temperature,the warmest month(July) average temperature and the annual average temperature.The results show that:(1) Pinus massoniana and Pinus tabulaeformis forests and the climate indicators of their boundary can be used as one of the vegetation-climate indexes for the delimitation of subtropical and warm temperate zones.The boundary between the subtropical coniferous forest(Pinus massoniana forest) and temperate coniferous forest(Pinus tabulaeformis forest) is located along the south slope of Funiu Mountain to the north edge of Hanzhong Basin(the south slope of Qinling Mountains) at an altitude of 1000–1200 m,where the climatic indictors are stable:the annual precipitation is about 750–1000 mm,the annual average temperature is about 12–14℃,the coldest monthly average temperature is 0–4℃,and the warmest monthly average temperature is about 22–26℃.(2) It can be more scientifically to delimitate the boundary of subtropical and warm temperate zones in China by comprehensively considering the vegetation-climate indicators.Additionally,the boundary between subtropical and warm temperate zones in Qinling-Daba Mountains should be a transitional zone consisting of the boundaries of coniferous forests,broad-leaved forests and shrubs between subtropical and warm temperate zones.The results provide a scientific basis for the selection of delimitation index of subtropical and warm temperate zones.展开更多
The anatomic research on the mutant clone of Pinus tabulaeformis Carr. in the seed orchard in Xingcheng, Liaoning Province was carried out. The female cone of the mutant clone looked like normal, but its ovules degene...The anatomic research on the mutant clone of Pinus tabulaeformis Carr. in the seed orchard in Xingcheng, Liaoning Province was carried out. The female cone of the mutant clone looked like normal, but its ovules degenerated in the early stage. This paper tries to find out the reason and time of ovule abortion. It seems that the ovule abortion is probably caused by female sterility because the microspores of this mutant clone were normal. Through the serial observations on the one-year-old macrosporangiates and the ovules of two-year-old female cones of mutant and normal clone, it is found that the reason of ovule abortion in mutant clone is the failure of the mitosis of free nuclei in the female gametophyte, and the time is about in the early April.展开更多
To determine the relationship between female sterility of Pinus tabulaeformis Carr. and plant hormones, content changes of several endogenous plant hormones in a female-sterile clone and a normal clone were analyzed d...To determine the relationship between female sterility of Pinus tabulaeformis Carr. and plant hormones, content changes of several endogenous plant hormones in a female-sterile clone and a normal clone were analyzed during the key period of female gametophyte abortion in mutant clones. The change of ABA content showed a similar pattern between normal and mutant clones, but the ABA content of the mutant clone was always much higher than that of the normal clone. In the normal clone, the IAA content decreased significantly at the early stage of the period and reached its minimum during the first ten days of April and stabilized thereafter. The endogenous ZR levels increased sharply at the early stages and reached a maximum in the middle of April, then decreased dramatically. The IAA and ZR contents of the mutant clone did not change perceptively through the entire period. We conclude that the high levels of ABA and the deficit of IAA and ZR may be the reasons of female gametophyte abortion in the female-sterile clones of P. tabulaeformis.展开更多
A tree-ring width chronology developed from Pinus tabulaeformis tree-rings of Hasi Mountain was employed to analyze responses of tree-ring to different climatic metrics.Correlation analyses between tree-ring chronolog...A tree-ring width chronology developed from Pinus tabulaeformis tree-rings of Hasi Mountain was employed to analyze responses of tree-ring to different climatic metrics.Correlation analyses between tree-ring chronology and precipitation and temperature suggest that tree growth is both limited by precipitation and temperature,and moisture is the principal limiting factor of tree-ring width.To find a suitable moisture index to be reconstructed,three moisture indices considering precipitation and evaporation even water balance are chosen to be analyzed.The results suggest that the PDSI is an appropriate index as predictor of tree-ring width and can be used to reconstruct in this area.展开更多
In order to test whether the relationship between climate and the radial growth of trees is affected by altitude,altitude variability and time stability of climate-influenced radial growth of a dominant conifer,Chines...In order to test whether the relationship between climate and the radial growth of trees is affected by altitude,altitude variability and time stability of climate-influenced radial growth of a dominant conifer,Chinese pine(Pinus tabulaeformis),in the eastern Qilian Mountains were studied against the background of climate change using dendrochronology.Results show that 1)droughts at the end of the growing season of last year and during the early and middle growing season of the current year were the main limiting factors for the radial growth of Chinese pine at two altitude gradients;this was determined by analyzing the relationship between tree-ring width chronologies and climate factors.2)The sensitivity of the radial growth of trees to climate change gradually decreased and was affected more by drought stress at a lower altitude.3)An unstable divergence response was observed in the radial growth at the two altitudes,in response to controlling climatic factors;this observation was based on the moving correlation analysis of growth/climate relationships,and the aggravation of drought stress caused by increasing temperature was the main reason.4)The growth rate of Chinese pine at the two altitudes increased at first and then decreased,as measured by basal area increment(BAI)modeling.Future temperature rises may have significant effects on mountain forest ecosystems in arid and semi-arid regions.Effective management and protection measures should be taken,according to the response patterns of trees to climate change at different altitude gradients.展开更多
In order to know well the relationship between vegetation and water in North China, especially Beijing, with exceptional water resources, we studied the characteristics of flow production and sediment production under...In order to know well the relationship between vegetation and water in North China, especially Beijing, with exceptional water resources, we studied the characteristics of flow production and sediment production under different rainfall intensities by artificial rainfall simulation device. Results showed that increase of rainfall intensity would prolong the whole process of flow production, and vegetation on the slope would delay that process. Within the same duration, total runoff volume of each runoff plot and rainfall intensity had significant linear relationship. When vegetation kept unchanged, runoff velocity increased significantly with the increase of rainfall intensity, and owing to the formation of low permeable layer, the velocity increased fiercely during the early 3 minutes, reached stable at 10 - 15 minute. With the same rain intensity, total sediment yield decreased with rise of vegetation coverage, but increased obviously with rise of rain intensity and effectiveness of controlling sediment about 1 m x 1 m Pinus tabulaeformis stand decreased firstly and then increased, while that about 1.5 m x 1.5 m Pinus tabulaeformis stand kept decreasing. Since the tags with A, B and C for 0.42 mm/min, 0.83 mm/min, 1.29 mm/min, order of sediment concentration of wasteland plot was B > C > A, and 1 m x 1 m Pinus tabulaeformis plot B > A > C. Through this study, some suggestions were expected to be provided for water balance of Beijing area and certain basis for construction of shelter forest.展开更多
The growth of Pinus tabulaeformis is influenced by the sonsau cocuus sinensis chen. When the insect density is more than 300-350 head/hundred beam conifer, sonsau cocuus sinensis chen occurred significantly influence ...The growth of Pinus tabulaeformis is influenced by the sonsau cocuus sinensis chen. When the insect density is more than 300-350 head/hundred beam conifer, sonsau cocuus sinensis chen occurred significantly influence the Pinus tabulaeformis＇ s growth. when the insect density reached 250-300 head/100 beam coniferous, sonsau cocuus sinensis chen significantly influence the accumulation of Pinus tabulaeformis volume. To determine the sonsau cocuus sinensis chen 2nd instar nymph theory control index was 220.5 / hundred beam needles has a guiding significance to the production practice.展开更多
Pinus tabulaeformis is one of the common forest resource tree species in the northern region of our country. It has high market economic value. In recent years, with the vigorous development of artificial afforestatio...Pinus tabulaeformis is one of the common forest resource tree species in the northern region of our country. It has high market economic value. In recent years, with the vigorous development of artificial afforestation projects in our country, afforestation technology and afforestation methods are becoming more and more mature, further improving the coverage rate of forest resources in our country and improving the ecological environment. Pinus tabulaeformis is widely distributed in many regions of China, and is also one of the important tree species for afforestation projects in China. In the work of seedling raising of Pinus tabulaeformis, plant growth regulators can be appropriately used to improve the growth mechanism of Pinus tabulaeformis, promote the healthy growth of Pinus tabulaeformis and improve the ability to resist diseases and insect pests. The test results were compared and analyzed to detect the emergence rate of Pinus tabulaeformis seedlings, including the growth status of Pinus tabulaeformis seedlings and the growth quality of Pinus tabulaeformis. The research shows that GGR6 plant regulator can obviously improve the emergence rate of Pinus tabulaeformis with the emergence rate as high as 92%. Compared with the control area (clear water), the emergence rate of Pinus tabulaeformis is obviously higher than that of the control area 2-3 days in advance, and the emergence situation is good, the seedlings are neat and the color is pure. Finally, the conclusion is drawn that the application of GGR6 plant regulator has an auxiliary effect on the seedlings of Pinus tabulaeformis and can promote the growth of the seedlings, with very obvious effect.展开更多
The defense mechanisms induced in wild Chinese pine(Pinus tabuliformis)in response to herbivores are not well characterized,especially in the field.To address this knowledge gap,we established a biological model syste...The defense mechanisms induced in wild Chinese pine(Pinus tabuliformis)in response to herbivores are not well characterized,especially in the field.To address this knowledge gap,we established a biological model system to evaluate proteome variations in pine needles after feeding by the Chinese pine caterpillar(Dendrolimus tabulaeformis),a major natural enemy and dominant herbivore.Quantitative tandem mass tag(TMT)proteomics and bioinformatics were utilized to systematically identify differentially abundant proteins implicated in the induced defense response of Chinese pine.We validated key protein changes using parallel reaction monitoring(PRM)technology.Pathway analysis revealed that the induced defenses involved phenylpropanoid,coumarin,and flavonoid biosynthesis,among other processes.To elucidate the regulatory patterns underlying pine resistance,we determined the activities of defense enzymes and levels of physiological and biochemical compounds.In addition,the expression of upstream genes for key proteins was validated by qRT-PCR.Our results provide new molecular insights into the induced defense mechanisms in Chinese pine against this caterpillar in the field.A better understanding of these defense strategies will inform efforts to breed more-resistant pine varieties.展开更多
The pine caterpillar, Dendrolimus tabulaeformis is one of the most important pests on Pinus tabulaeformis and other pine species in North China. In the present study, effects of relative humidity （RH） on the develop...The pine caterpillar, Dendrolimus tabulaeformis is one of the most important pests on Pinus tabulaeformis and other pine species in North China. In the present study, effects of relative humidity （RH） on the development and survival of pine caterpillars and soil moisture （SM） on their diapausing larvae were investigated. Low RH （20%） deferred the development of eggs and larvae, reduced egg hatching and larval surviving compared to 40%, 60% and 80% RH. Both low （20%） and high （100%） RH reduced egg hatching, but only 20% RH deferred the development of larvae, prolonged developmental duration and reduced the body mass and body length of larvae. The SM influenced the survival of diapausing larvae significantly. The dry treatment significantly reduced the supercooling points （SCPs）, whereas increased the mortality and reduced body mass from 56.9 to 36.5 mg and body water content from 78% to 63% after 2 weeks＇ exposure. Therefore, higher RH is more favorable for the development of early instars and survival of diapausing larvae of the pine caterpillars.展开更多
In order to study seed quality changes of main afforestation species under high temperature and high relative humidity, the deterioration mechanism of seeds of Robinia pesudoacacia and Pinus tabulaeformis from arid an...In order to study seed quality changes of main afforestation species under high temperature and high relative humidity, the deterioration mechanism of seeds of Robinia pesudoacacia and Pinus tabulaeformis from arid and semiarid areas of Northern China was elucidated in this study. The seeds were artificially aged for 2 and 6 d at the temperature of 45 oC and the relative humidity (RH) of 50%, 75% and 100% , respectively. The results showed that the germinability decreased and the cell membrane deteriorated with the artificial ageing. The decrease in germinability was well correlated with the decreased activities of dehydrogenase and α-amylase. After 6-day accelerated ageing, the seed germination and the activities of dehydrogenase and α-amylase decreased to a great extent for both species of seeds. The results suggest that seed deterioration during accelerated ageing is closely related to the increase of relative conductivity and the decrease of dehydrogenase and α-amylase activities.展开更多
In the paper, the hydraulic architecture parameters of Pinus tabulaeformis seedlings (4 years old)were measured by improved flushing method under normal water condition in the green house and the basictheory of hydrau...In the paper, the hydraulic architecture parameters of Pinus tabulaeformis seedlings (4 years old)were measured by improved flushing method under normal water condition in the green house and the basictheory of hydraulic architecture is used to discuss the rationality of the pipe model. The results of theexperiment and simulation show that the differences of hydraulic conductivity, specific conductivity and leafspecific conductivity is great in different stems and branches of Pinus tabulaeformis seedlings. The hydraulicconductivity of non-constriction area is higher than that of constriction area. The devotion of functionalxylem of stem to unit leaf growth is not a constant, namely, the Huber value is diverse. Even though the pipemodel has been accepted in some areas, its precondition is not perfect, and it is helpless in correctlyunderstanding the essence of water transport in seedlings from the prospective of water physiology.展开更多
文摘The stimulative effect of trace elements on seed germination and seedling growth of Pinus tabulaeformis was tested. The experiments were carried out on seed soak and topdressing with different trace elements and varied concentrations at the nursery of Gardens Research Institute, Harbin, in 2000-2001. The experimental results showed that soaking seed with 1% and 0.2% concentrations of Mn element produced best result for seed germination, and the germination rate was increased by 9%~19% for the seeds treated with 1% concentration and 12%~14% for the seeds treated with 0.2% concentration compared with the control group. The seeds treated with boron element had lowest germination rate. For trace element topdressing, Mn and Mo elements presented good result for seedling growth and the treatment with low concentration was even better. The height or chlorophyll content of the seedlings with spray of low-concentration Mn and Mo element was much higher than that of untreated ones. In the contrast to the treating method of seed soak, topdressing (application of spraying on foliage) had evident effect on seedling growth.
文摘In an earlier report the ultrastructure and nucleoid organelles of male gamete in Pinus tabulaeformis Carr. have been described. Presently, the ultrastructure of the cytoplasm of the egg cell and pollen tube—immediately before fertilization and during cytoplasmic transmission of male gametophyte—has been described for the same species. The fate of parental plastids and mitochondria in the proembryo has also been followed. The mature egg cell contains a large amount of mitochondria, but seems to lack normal plastids. Most plastids have transformed into large inclusions. Apart from the large inclusions, there are abundant small inclusions and other organelles in the egg cell. During fertilization, pollen tube penetrates into the egg cell at the micropylar end and thereafter the contents are released. Plastid and mitochondrion of male origin are lacking near the fusing sperm_egg nuclei. The second sperm nucleus—not involved in karyogamy—remains at a site near the receptive vacuole. This nucleus is surrounded by large amount of male cytoplasm containing mixed organelles from the sperm cell, tube cell, and egg cell. At the free nuclear proembryo stage, organelles of male and female origin are visible in the perinucleus_cytoplasmic zone. Most of the mitochondria have the same morphological features as those in the egg cell. Some of the mitochondria appear to have originated from the sperm and tube cells. Plastids are most likely of male gametophyte origin because they have similar appearance as those of the sperm and tube cell. Large inclusions in the egg cell become vacuole_like. Paternal plastids have been incorporated into the neocytoplasm of the proembryo. In the cellular proembryo, maternal mitochondria are more abundant. Plastids resembling those of the sperm and tube cell are still present. These cytological results clearly show that in P. tabulaeformis, plastids are inherited paternally and mitochondria bipaternally. The cytological mechanism of plastid and mitochondrion inheritance in gymnosperm is discussed.
文摘The cytological mechanism of plastid and mitochondrion inheritance in Pinus is an interesting research topic with only a limited number of published articles. The results indicate that the sperms of Pinus tabulaeformis Carr. contain abundant plastids, mitochondria and organelle DNA. These data provide reliable cytological evidence of paternal plastid and mitochondrion inheritance in Pinus . The results are in line with the confirmed general rule of paternal plastid inheritance in Pinaceae. But whether mitochondria in sperm cells can be transmitted into the embryos is an issue needs further developmental studies. Another important finding is that contrary to earlier classification of the male gamete of Pinaceae into the male nuclei type, the results reveal that male gametes in Pinus tabulaeformis are actually cells. However, the sperm cells are only surrounded by plasma membranes without cell walls. The larger leading sperm cell in a pollen tube section is long in shape, with a large amount of cytoplasm; while the second sperm cell is smaller, round in shape and contains less cytoplasm. Whether this feature of the male gamete type could be considered as a representative characteristic of the family is discussed and further conclusions await more experimental evidences from studies on plants from different species.
基金supported by the ‘‘Doctoral Scientific Research Foundation’’ of Heilongjiang Bayi Agricultural University,Grant No.XDB2015-02 and the ‘‘Strategic Priority Research Program’’ of the Chinese Academy of Sciences,Grant No.XDA05050203-04-01
文摘Although carbon(C), nitrogen(N), and phosphorous(P) stoichiometric ratios are considered good indicators of nutrient excess/limitation and thus of ecosystem health, few reports have discussed the trends and the reciprocal effects of C:N:P stoichiometry in plant–litter–soil systems. The present study analyzed C:N:P ratios in four age groups of Chinese pine, Pinus tabulaeformis Carr., forests in Shanxi Province, China: plantation young forests(AY,<20 year-old); plantation middle-aged forests(AM, 21–30 year-old); natural young forests(NY,<30 year-old); and natural middle-aged forests(NM,31–50 year-old). The average C:N:P ratios calculated for tree, shrub, and herbaceous leaves, litter, and soil(0–100 cm) were generally higher in NY followed by NM,AM, and AY. C:N and C:P ratios were higher in litter than in leaves and soils, and reached higher values in the litter and leaves of young forests than in middle-aged forests;however, C:N and C:P ratios were higher in soils of middle-aged forests than in young forests. N:P ratios were higher in leaves than in litter and soils regardless of stand age; the consistent N:P<14 values found in all forests indicated N limitations. With plant leaves, C:P ratios were highest in trees, followed by herbs and shrubs, indicating a higher efficiency in tree leaf formation. C:N ratios decreased with increasing soil depth, whereas there was no trend for C:P and N:P ratios. C:N:P stoichiometry of forest foliage did not exhibit a consistent variation according to stand age. Research on the relationships between N:P, and P, N nutrient limits and the characteristics of vegetation nutrient adaptation need to be continued.
基金Supported by National Natural Science Foundation of China(No.31101781)China Scholarship Council(CSC)+1 种基金Science and Technology Development Program of Jilin Province(No.20140204022NY)Interdisciplinary Innovation Fund of Jilin University(No.905070166006,No.450060481143)~~
文摘[Objective] This study aimed to investigate the optimal technological condi- tions for ultrasouqd-assisted extraction of polysaccharides from Pinus tabulaeformis seed shells. [Melhod] Polysaccharides were extracted from P. tabulaeformis seed shells by ultrasound-assisted hot water extraction method and detected by phenol- concentrated sulfuric acid method. The effect of extraction temperature, extraction duration, solid-liquid ratio and extraction frequency on the extraction of polysaccha- rides was investigated using single-factor gradient experiment and the extraction conditions for polysaccharides from P. tabulaeformis seed shells were optimized us- ing L9（34） orthogonal design. [Result] The content of polysaccharides extracted twice at 60 ℃ for 25 min with solid-liquid ratio of 1：3.5 reached the maximum. The re- covery rate （n=-5） ranged from 97.71% to 100.67% and RSD was 1.56%, suggesting high stability. [Conclusion] A simple and efficient method for ultrasound-assisted ex- traction of polysaccharides from P. tabulaeformis seed shells was established in this study, which laid solid foundation for the development and utilization of abandoned pine nut shell resources.
基金National Natural Science Foundation of China,No.41871350Scientific and Technological Basic Resources Survey Project,No.2017FY100900。
文摘The Qinling Mountains is not only the geographical boundary between North and South China,but also the boundary between subtropical and warm temperate zones.It plays an important role in the geo-ecological pattern of China.However,there is controversy about the specific location of this geographical boundary in academic community due to the complexity,transition and heterogeneity of the transitional zone,as well as the differences in the delimitation indicators and research purposes.To further reveal the characteristics of the North-South transitional zone and clarify the specific location of the geo-ecological boundary between North and South China,combined with SRTM topographic data,temperature and precipitation data,Pinus massoniana forest and Pinus tabulaeformis forest,which represent subtropical coniferous forest in South China and temperate coniferous forest in North China respectively,were chosen to analyze their spatial distributions in the Qinling-Daba Mountains and the climatic conditions at their boundary with the climatic indexes of annual precipitation,the coldest month(January) average temperature,the warmest month(July) average temperature and the annual average temperature.The results show that:(1) Pinus massoniana and Pinus tabulaeformis forests and the climate indicators of their boundary can be used as one of the vegetation-climate indexes for the delimitation of subtropical and warm temperate zones.The boundary between the subtropical coniferous forest(Pinus massoniana forest) and temperate coniferous forest(Pinus tabulaeformis forest) is located along the south slope of Funiu Mountain to the north edge of Hanzhong Basin(the south slope of Qinling Mountains) at an altitude of 1000–1200 m,where the climatic indictors are stable:the annual precipitation is about 750–1000 mm,the annual average temperature is about 12–14℃,the coldest monthly average temperature is 0–4℃,and the warmest monthly average temperature is about 22–26℃.(2) It can be more scientifically to delimitate the boundary of subtropical and warm temperate zones in China by comprehensively considering the vegetation-climate indicators.Additionally,the boundary between subtropical and warm temperate zones in Qinling-Daba Mountains should be a transitional zone consisting of the boundaries of coniferous forests,broad-leaved forests and shrubs between subtropical and warm temperate zones.The results provide a scientific basis for the selection of delimitation index of subtropical and warm temperate zones.
基金National Natural Science Foundation of China(Grant No.39970602)
文摘The anatomic research on the mutant clone of Pinus tabulaeformis Carr. in the seed orchard in Xingcheng, Liaoning Province was carried out. The female cone of the mutant clone looked like normal, but its ovules degenerated in the early stage. This paper tries to find out the reason and time of ovule abortion. It seems that the ovule abortion is probably caused by female sterility because the microspores of this mutant clone were normal. Through the serial observations on the one-year-old macrosporangiates and the ovules of two-year-old female cones of mutant and normal clone, it is found that the reason of ovule abortion in mutant clone is the failure of the mitosis of free nuclei in the female gametophyte, and the time is about in the early April.
基金Supported by the National Natural Science Foundation of China (Grant No. 30371144) and Postgraduate Foundation of Beijing Forestry University
文摘To determine the relationship between female sterility of Pinus tabulaeformis Carr. and plant hormones, content changes of several endogenous plant hormones in a female-sterile clone and a normal clone were analyzed during the key period of female gametophyte abortion in mutant clones. The change of ABA content showed a similar pattern between normal and mutant clones, but the ABA content of the mutant clone was always much higher than that of the normal clone. In the normal clone, the IAA content decreased significantly at the early stage of the period and reached its minimum during the first ten days of April and stabilized thereafter. The endogenous ZR levels increased sharply at the early stages and reached a maximum in the middle of April, then decreased dramatically. The IAA and ZR contents of the mutant clone did not change perceptively through the entire period. We conclude that the high levels of ABA and the deficit of IAA and ZR may be the reasons of female gametophyte abortion in the female-sterile clones of P. tabulaeformis.
基金Natural Science Foundation of China （41071128, 40801004） Fundamental Research Funds for the Central Universities
文摘A tree-ring width chronology developed from Pinus tabulaeformis tree-rings of Hasi Mountain was employed to analyze responses of tree-ring to different climatic metrics.Correlation analyses between tree-ring chronology and precipitation and temperature suggest that tree growth is both limited by precipitation and temperature,and moisture is the principal limiting factor of tree-ring width.To find a suitable moisture index to be reconstructed,three moisture indices considering precipitation and evaporation even water balance are chosen to be analyzed.The results suggest that the PDSI is an appropriate index as predictor of tree-ring width and can be used to reconstruct in this area.
基金This research was supported by the National Natural Science Foundation of China(Grant No.41861006)Project/Supported by State Key Laboratory of Earth Surface Processes and Resource Ecology(Grant No.2020-KF04)the Research Ability Promotion Program for Young Teachers of Northwest Normal University(NWNU-LKQN2019-4).
文摘In order to test whether the relationship between climate and the radial growth of trees is affected by altitude,altitude variability and time stability of climate-influenced radial growth of a dominant conifer,Chinese pine(Pinus tabulaeformis),in the eastern Qilian Mountains were studied against the background of climate change using dendrochronology.Results show that 1)droughts at the end of the growing season of last year and during the early and middle growing season of the current year were the main limiting factors for the radial growth of Chinese pine at two altitude gradients;this was determined by analyzing the relationship between tree-ring width chronologies and climate factors.2)The sensitivity of the radial growth of trees to climate change gradually decreased and was affected more by drought stress at a lower altitude.3)An unstable divergence response was observed in the radial growth at the two altitudes,in response to controlling climatic factors;this observation was based on the moving correlation analysis of growth/climate relationships,and the aggravation of drought stress caused by increasing temperature was the main reason.4)The growth rate of Chinese pine at the two altitudes increased at first and then decreased,as measured by basal area increment(BAI)modeling.Future temperature rises may have significant effects on mountain forest ecosystems in arid and semi-arid regions.Effective management and protection measures should be taken,according to the response patterns of trees to climate change at different altitude gradients.
文摘In order to know well the relationship between vegetation and water in North China, especially Beijing, with exceptional water resources, we studied the characteristics of flow production and sediment production under different rainfall intensities by artificial rainfall simulation device. Results showed that increase of rainfall intensity would prolong the whole process of flow production, and vegetation on the slope would delay that process. Within the same duration, total runoff volume of each runoff plot and rainfall intensity had significant linear relationship. When vegetation kept unchanged, runoff velocity increased significantly with the increase of rainfall intensity, and owing to the formation of low permeable layer, the velocity increased fiercely during the early 3 minutes, reached stable at 10 - 15 minute. With the same rain intensity, total sediment yield decreased with rise of vegetation coverage, but increased obviously with rise of rain intensity and effectiveness of controlling sediment about 1 m x 1 m Pinus tabulaeformis stand decreased firstly and then increased, while that about 1.5 m x 1.5 m Pinus tabulaeformis stand kept decreasing. Since the tags with A, B and C for 0.42 mm/min, 0.83 mm/min, 1.29 mm/min, order of sediment concentration of wasteland plot was B > C > A, and 1 m x 1 m Pinus tabulaeformis plot B > A > C. Through this study, some suggestions were expected to be provided for water balance of Beijing area and certain basis for construction of shelter forest.
文摘The growth of Pinus tabulaeformis is influenced by the sonsau cocuus sinensis chen. When the insect density is more than 300-350 head/hundred beam conifer, sonsau cocuus sinensis chen occurred significantly influence the Pinus tabulaeformis＇ s growth. when the insect density reached 250-300 head/100 beam coniferous, sonsau cocuus sinensis chen significantly influence the accumulation of Pinus tabulaeformis volume. To determine the sonsau cocuus sinensis chen 2nd instar nymph theory control index was 220.5 / hundred beam needles has a guiding significance to the production practice.
文摘Pinus tabulaeformis is one of the common forest resource tree species in the northern region of our country. It has high market economic value. In recent years, with the vigorous development of artificial afforestation projects in our country, afforestation technology and afforestation methods are becoming more and more mature, further improving the coverage rate of forest resources in our country and improving the ecological environment. Pinus tabulaeformis is widely distributed in many regions of China, and is also one of the important tree species for afforestation projects in China. In the work of seedling raising of Pinus tabulaeformis, plant growth regulators can be appropriately used to improve the growth mechanism of Pinus tabulaeformis, promote the healthy growth of Pinus tabulaeformis and improve the ability to resist diseases and insect pests. The test results were compared and analyzed to detect the emergence rate of Pinus tabulaeformis seedlings, including the growth status of Pinus tabulaeformis seedlings and the growth quality of Pinus tabulaeformis. The research shows that GGR6 plant regulator can obviously improve the emergence rate of Pinus tabulaeformis with the emergence rate as high as 92%. Compared with the control area (clear water), the emergence rate of Pinus tabulaeformis is obviously higher than that of the control area 2-3 days in advance, and the emergence situation is good, the seedlings are neat and the color is pure. Finally, the conclusion is drawn that the application of GGR6 plant regulator has an auxiliary effect on the seedlings of Pinus tabulaeformis and can promote the growth of the seedlings, with very obvious effect.
基金supported by the Science and Technology Development Program of Hebei Agricultural University,the Research on Molecular Mechanisms of Population Differentiation and Adaptation of Forest Pests and Insects under Environmental Stress(grant No.:30771739)Forest Pests and Diseases(grant No.:1528003)the National Natural Science Foundation of China for the study of community regulatory mechanisms of insect pest pandemics in larch plantation forests(Grant No.:32371882).
文摘The defense mechanisms induced in wild Chinese pine(Pinus tabuliformis)in response to herbivores are not well characterized,especially in the field.To address this knowledge gap,we established a biological model system to evaluate proteome variations in pine needles after feeding by the Chinese pine caterpillar(Dendrolimus tabulaeformis),a major natural enemy and dominant herbivore.Quantitative tandem mass tag(TMT)proteomics and bioinformatics were utilized to systematically identify differentially abundant proteins implicated in the induced defense response of Chinese pine.We validated key protein changes using parallel reaction monitoring(PRM)technology.Pathway analysis revealed that the induced defenses involved phenylpropanoid,coumarin,and flavonoid biosynthesis,among other processes.To elucidate the regulatory patterns underlying pine resistance,we determined the activities of defense enzymes and levels of physiological and biochemical compounds.In addition,the expression of upstream genes for key proteins was validated by qRT-PCR.Our results provide new molecular insights into the induced defense mechanisms in Chinese pine against this caterpillar in the field.A better understanding of these defense strategies will inform efforts to breed more-resistant pine varieties.
基金This research was supported in part by the Key Program of National Natural Science Foundation of China （30330490） and China Spark Program （2006EA740049）.
文摘The pine caterpillar, Dendrolimus tabulaeformis is one of the most important pests on Pinus tabulaeformis and other pine species in North China. In the present study, effects of relative humidity （RH） on the development and survival of pine caterpillars and soil moisture （SM） on their diapausing larvae were investigated. Low RH （20%） deferred the development of eggs and larvae, reduced egg hatching and larval surviving compared to 40%, 60% and 80% RH. Both low （20%） and high （100%） RH reduced egg hatching, but only 20% RH deferred the development of larvae, prolonged developmental duration and reduced the body mass and body length of larvae. The SM influenced the survival of diapausing larvae significantly. The dry treatment significantly reduced the supercooling points （SCPs）, whereas increased the mortality and reduced body mass from 56.9 to 36.5 mg and body water content from 78% to 63% after 2 weeks＇ exposure. Therefore, higher RH is more favorable for the development of early instars and survival of diapausing larvae of the pine caterpillars.
基金subsidized by the project of "Study on Coming back of Vegetation and Technology of Afforestation in Northwest Farmingand Pasturing Mixed Area with Serious Corrosion (2006BAD03A0308)"which is a part of "Study on Key Technology of Afforestationin Barren Site (2006BAD03A03)".
文摘In order to study seed quality changes of main afforestation species under high temperature and high relative humidity, the deterioration mechanism of seeds of Robinia pesudoacacia and Pinus tabulaeformis from arid and semiarid areas of Northern China was elucidated in this study. The seeds were artificially aged for 2 and 6 d at the temperature of 45 oC and the relative humidity (RH) of 50%, 75% and 100% , respectively. The results showed that the germinability decreased and the cell membrane deteriorated with the artificial ageing. The decrease in germinability was well correlated with the decreased activities of dehydrogenase and α-amylase. After 6-day accelerated ageing, the seed germination and the activities of dehydrogenase and α-amylase decreased to a great extent for both species of seeds. The results suggest that seed deterioration during accelerated ageing is closely related to the increase of relative conductivity and the decrease of dehydrogenase and α-amylase activities.
文摘In the paper, the hydraulic architecture parameters of Pinus tabulaeformis seedlings (4 years old)were measured by improved flushing method under normal water condition in the green house and the basictheory of hydraulic architecture is used to discuss the rationality of the pipe model. The results of theexperiment and simulation show that the differences of hydraulic conductivity, specific conductivity and leafspecific conductivity is great in different stems and branches of Pinus tabulaeformis seedlings. The hydraulicconductivity of non-constriction area is higher than that of constriction area. The devotion of functionalxylem of stem to unit leaf growth is not a constant, namely, the Huber value is diverse. Even though the pipemodel has been accepted in some areas, its precondition is not perfect, and it is helpless in correctlyunderstanding the essence of water transport in seedlings from the prospective of water physiology.
