The features of branching and growth studied included height, diameter at breast height (DBH), total number of branches, annual height growth, annual branch elongation in the year of elongating, annual branch number f...The features of branching and growth studied included height, diameter at breast height (DBH), total number of branches, annual height growth, annual branch elongation in the year of elongating, annual branch number for four consecutive years, diameter of branches of different ages, and diameter of stem where branch-whorl originates. For features of total growth and overall branching, no significant differences were found between families, except for DBH. For annual features, no significant differences were found in annual stem height growth, annual branch elongation in the year of elongation and diameter of branches. In the last four years, differences in number of branches were not significant in the first two years but were significant in the last two year; differences in stem diameter where branch-whorls grow were significant for the four consecutive years. Trend of annual growth and branching features of families can be divided into three types as increasing type, stable type and fluctuating type. Most of families have an increasing type with respect of annual height growth and annual branch elongation, while most families belong to a fluctuating type with annual branch number. The results indicated that in the fifth year after planted in seedling seed orchard, differences between families were mostly insignificant. This result may have two main explanations: one is the growth rhyme in early ages of Masson pine, the other one is the complex paternal components to form the open-pollinated families. Family selection seemed to be not useful based on the result. It is suggested to select some of families in the nursery instead of to use all the families when establishing seedling seed orchards with open-pollinated families from plus-trees.展开更多
Excised zygotic embryos, cotyledons and hypocotyls of juvenile seedlings of masson pine were grown on DCR medium supplemented with several concentrations of various plant phytohormones. BA (1.0 mg/ L) in combination w...Excised zygotic embryos, cotyledons and hypocotyls of juvenile seedlings of masson pine were grown on DCR medium supplemented with several concentrations of various plant phytohormones. BA (1.0 mg/ L) in combination with NAA (0.05 mg/L)in DCR medium was found to increase the formation of adventitious buds from mature zygotic embryos, but most of them were formed at the tips of embryonic cotyledons. Adventitious buds were obtained from cotyledons and hypocotyls from juvenile seedlings when they were cultured on DCR medium containing BA 3-5 mg/L and NAA 0.1-0.2 mg/L. Elongation of buds were observed on hormone-free DCR medium with or without activated charcoal (0.5%). Root initiation was achieved with full or half strength DCR inedium supplemented with IBA 1.0 mg/L and NAA 0.25-0.5 mg/L. Approximately 11-20 axillary buds formed on each explant when juvenile seedling explants were treated (3-20h) with BA 50-100 mg/L, followed by transfer to hormone-free DCR medium. The maximum number of shoots obtained per explant within six months was 33.展开更多
Dendrolimus punctatus Walker is a major pest affecting Pinus massoniana Lamb.forests and can cause serious economic and ecological losses.WRKY transcription factors play important roles in coping with various environm...Dendrolimus punctatus Walker is a major pest affecting Pinus massoniana Lamb.forests and can cause serious economic and ecological losses.WRKY transcription factors play important roles in coping with various environmental stresses and plant responses against herbivorous insects.However,the mechanisms underlying the actions of WRKY in the defense responses of D.punctatus in P.massoniana are still unclear.Our previous study provided evidence that WRKY plays an important role in the insect resistance of P.massoniana.In this study,the treatments of exogenous hormones and Ca^(2+) increased the concentrations of endogenous hormones,and terpenoid synthases in P.massoniana effectively improving its resistance to D.punctatus.After analyzing the WRKY family of P.massoniana,PmWRKY31 was selected and studied.A direct interaction between PmWRKY31 and PmLp8 was observed by yeast double hybridization assay.Gene expression analysis showed that treatments of exogenous hormones and Ca^(2+)induced high PmWRKY31 expression.The expression pattern of PmWRKY31 was different under treatment of MeJA compared to those of GA,ABA and SA.These results indicated that PmWRYK31 and PmLp8 interacted with each other to promote the expression of terpenoid synthase genes and increase the content of terpenoid volatile substances by regulating the gene expression of hormone signaling pathways,to improve the ability of P.massoniana to resist D.punctatus,providing theoretical support for the involvement of WRKY transcription factors in enhancement of the insect resistance of P.massoniana through their regulation of hormone signaling.展开更多
[Objectives]To study the antibacterial effects of extracts from Pinus massoniana Lamb.needles.[Methods]In this experiment,the components from Pinus massoniana Lamb.needles were extracted by systematic solvent extracti...[Objectives]To study the antibacterial effects of extracts from Pinus massoniana Lamb.needles.[Methods]In this experiment,the components from Pinus massoniana Lamb.needles were extracted by systematic solvent extraction method,and the antibacterial activity against four common bacteria,Escherichia coli,Staphylococcus aureus,Bacillus subtilis,Aspergillus flavus and the antibacterial active component were examined for by punch method.[Results]Different solvent extraction rate was different,the rates of petroleum ether,chloroform,ethyl acetate,n-butanol,water extracts were 4.2%,16.7%,17.4%,21.1%,40.6%.All extracts showed inhibitory effect against test bacteria.It was observed that the inhibition of G+was stronger than G-,and the extracts had the best antibacterial activity to Staphylococcus aureus while the weakest to Aspergillus flavus.The antibacterial activity of the components decreased in the order:ethyl acetate extract>n-butanol extract>chloroform extract>petroleum ether extract>aqueous phase.The extracts were stable under ultraviolet radiation(UV)light and long term storage.The antibacterial activity of the extracts was weaker with the increase of pH value when the pH value≤8.[Conclusions]It is inferred that the antibacterial components in the extract of Pinus massoniana needles are widely distributed,and the components with medium polarity or above are the main antibacterial components.展开更多
在结构健康监测(Structural Health Monitoring,SHM)技术中,基于Lamb波的损伤监测方法在板状结构中显示出了巨大的潜力。提出了一种基于近似非凸鲁棒主成分分析(Approximate Non-Convex Robust Principal Component Analysis,ANC-RPCA)...在结构健康监测(Structural Health Monitoring,SHM)技术中,基于Lamb波的损伤监测方法在板状结构中显示出了巨大的潜力。提出了一种基于近似非凸鲁棒主成分分析(Approximate Non-Convex Robust Principal Component Analysis,ANC-RPCA)的异常值分析方法。该算法对于高维测量信号,能够在降维条件下实现有效的损伤诊断。通过使用秩近似函数逼近矩阵的秩,采用非凸惩罚函数逼近?_(0)范数,非凸惩罚函数在一定条件下可以保证稀疏解的唯一性。随着数据矩阵规模的扩大,传统的RPCA采用核范数近似时,奇异值分解的计算复杂度也会上升。新的近似方法能在使计算效率更高的情况下,针对波场图像能够在更低秩的水平下保留有效信息,识别出异常值。将该算法运用到基于Lamb波的波场图像中,通过仿真和实验数据验证其有效性,使用非精确增广拉格朗日乘子(Inexact Augmented Lagrange Multiplier,IALM)法求解,并与目前使用较多的主流RPCA算法进行了效果对比。实验结果表明ANC-RPCA算法在异常值识别中具有良好的性能,相较于其他算法,在计算效率和低秩性等方面具有巨大的优势,证明了所提算法的可靠性和完整性。展开更多
为提高层合板损伤检测的准确性与灵敏度,基于聚偏二氟乙烯(polyvinylidene fluoride,PVDF)梳状换能器激发的零群速度(zero group velocity,ZGV)Lamb波,提出了一种层合板损伤的检测方法。采用二维时域有限元方法,研究了PVDF梳状换能器对...为提高层合板损伤检测的准确性与灵敏度,基于聚偏二氟乙烯(polyvinylidene fluoride,PVDF)梳状换能器激发的零群速度(zero group velocity,ZGV)Lamb波,提出了一种层合板损伤的检测方法。采用二维时域有限元方法,研究了PVDF梳状换能器对零群速度Lamb波的激励,通过改变层合板中铝层杨氏模量来表征不同的损伤程度,分析了PVDF梳状换能器电压响应特性与层合板损伤程度之间的关系。结果表明:采用PVDF梳状换能器能够有效激励零群速度Lamb波,并获得层合板内部的状态信息。随着损伤程度的增加,PVDF梳状换能器响应的零群速度共振峰频域幅值随着铝层杨氏模量的减小而显著减少,进而灵敏地评价层合板损伤变化。研究结果说明优化设计的PVDF梳状换能器在零群速度Lamb波的激发与接收性能上都具有优越性,能够有效检测层合板损伤情况。展开更多
The Tongbai Mountains is an ecologically sensi-tive region and the northern boundary of Pinus massoniana Lamb.To analyze the effect of different microenvironments on tree growth response to climate factors,we develope...The Tongbai Mountains is an ecologically sensi-tive region and the northern boundary of Pinus massoniana Lamb.To analyze the effect of different microenvironments on tree growth response to climate factors,we developed standard chronologies for earlywood width(EWW),late-wood width(LWW),and total ring width(TRW)of P.massoniana at two sampling sites on slopes with different orientations,then analyzed characteristics of the chronolo-gies and their correlations with climate variables from five stations in the region and with a regional normalized differ-ence vegetation index(NDVI).Statistical results showed that the TRW/EWW/LWW chronology consistency and charac-teristics(mean sensitivity,signal to noise ratio,expressed population signal)for trees growing on the southeastern slope were much higher than for trees on the northeastern slope.Correlations indicated that temperature in current March and August has a significant positive effect on TRW/EWW/LWW formation,and the effect on the northeastern slope was weaker than on the southeastern slope.Compared to temperature,precipitation has more complicated effects on tree growth,but the effect on the northeastern slope was also generally weaker than on the southeastern slope.Step-wise linear regression analyses showed that temperature in August was the main limiting factor at the two sampling sites.Similarly,the response of tree growth on the southeast-ern slope as determined by the NDVI is better than on the northeastern slope,and the TRW/EWW/LWW chronologies for the southeastern slope explained over 50%of the total NDVI variances in June.Overall,the results indicate that the difference in the climate response of P.massoniana at two sampling sites is clearly caused by differences in the microenvironment,and such differences should be properly considered in future studies of forest dynamics and climate reconstructions.展开更多
基金This paper was a part of the National Key Project of Science and Technology on Masson Pine breeding during 1996-2000.
文摘The features of branching and growth studied included height, diameter at breast height (DBH), total number of branches, annual height growth, annual branch elongation in the year of elongating, annual branch number for four consecutive years, diameter of branches of different ages, and diameter of stem where branch-whorl originates. For features of total growth and overall branching, no significant differences were found between families, except for DBH. For annual features, no significant differences were found in annual stem height growth, annual branch elongation in the year of elongation and diameter of branches. In the last four years, differences in number of branches were not significant in the first two years but were significant in the last two year; differences in stem diameter where branch-whorls grow were significant for the four consecutive years. Trend of annual growth and branching features of families can be divided into three types as increasing type, stable type and fluctuating type. Most of families have an increasing type with respect of annual height growth and annual branch elongation, while most families belong to a fluctuating type with annual branch number. The results indicated that in the fifth year after planted in seedling seed orchard, differences between families were mostly insignificant. This result may have two main explanations: one is the growth rhyme in early ages of Masson pine, the other one is the complex paternal components to form the open-pollinated families. Family selection seemed to be not useful based on the result. It is suggested to select some of families in the nursery instead of to use all the families when establishing seedling seed orchards with open-pollinated families from plus-trees.
文摘Excised zygotic embryos, cotyledons and hypocotyls of juvenile seedlings of masson pine were grown on DCR medium supplemented with several concentrations of various plant phytohormones. BA (1.0 mg/ L) in combination with NAA (0.05 mg/L)in DCR medium was found to increase the formation of adventitious buds from mature zygotic embryos, but most of them were formed at the tips of embryonic cotyledons. Adventitious buds were obtained from cotyledons and hypocotyls from juvenile seedlings when they were cultured on DCR medium containing BA 3-5 mg/L and NAA 0.1-0.2 mg/L. Elongation of buds were observed on hormone-free DCR medium with or without activated charcoal (0.5%). Root initiation was achieved with full or half strength DCR inedium supplemented with IBA 1.0 mg/L and NAA 0.25-0.5 mg/L. Approximately 11-20 axillary buds formed on each explant when juvenile seedling explants were treated (3-20h) with BA 50-100 mg/L, followed by transfer to hormone-free DCR medium. The maximum number of shoots obtained per explant within six months was 33.
基金supported by The Natural Science Foundation of China(32060348,31660219)The special fund for Bagui scholar and Bagui young scholar,The Guangxi Natural Science Foundation(2018GXNSFAA294057,2019GXNSFDA245033,2019GXNSFBA245064)the Guangxi Science and Technology and Talents Special Project(AD19254004).
文摘Dendrolimus punctatus Walker is a major pest affecting Pinus massoniana Lamb.forests and can cause serious economic and ecological losses.WRKY transcription factors play important roles in coping with various environmental stresses and plant responses against herbivorous insects.However,the mechanisms underlying the actions of WRKY in the defense responses of D.punctatus in P.massoniana are still unclear.Our previous study provided evidence that WRKY plays an important role in the insect resistance of P.massoniana.In this study,the treatments of exogenous hormones and Ca^(2+) increased the concentrations of endogenous hormones,and terpenoid synthases in P.massoniana effectively improving its resistance to D.punctatus.After analyzing the WRKY family of P.massoniana,PmWRKY31 was selected and studied.A direct interaction between PmWRKY31 and PmLp8 was observed by yeast double hybridization assay.Gene expression analysis showed that treatments of exogenous hormones and Ca^(2+)induced high PmWRKY31 expression.The expression pattern of PmWRKY31 was different under treatment of MeJA compared to those of GA,ABA and SA.These results indicated that PmWRYK31 and PmLp8 interacted with each other to promote the expression of terpenoid synthase genes and increase the content of terpenoid volatile substances by regulating the gene expression of hormone signaling pathways,to improve the ability of P.massoniana to resist D.punctatus,providing theoretical support for the involvement of WRKY transcription factors in enhancement of the insect resistance of P.massoniana through their regulation of hormone signaling.
基金Supported by Zhanjiang Non-funded Science and Technology Research Plan in 2023(2023B01023)School-level Education and Teaching Reform Project of Lingnan Normal University in 2022(LingShiJiaoWu2022154).
文摘[Objectives]To study the antibacterial effects of extracts from Pinus massoniana Lamb.needles.[Methods]In this experiment,the components from Pinus massoniana Lamb.needles were extracted by systematic solvent extraction method,and the antibacterial activity against four common bacteria,Escherichia coli,Staphylococcus aureus,Bacillus subtilis,Aspergillus flavus and the antibacterial active component were examined for by punch method.[Results]Different solvent extraction rate was different,the rates of petroleum ether,chloroform,ethyl acetate,n-butanol,water extracts were 4.2%,16.7%,17.4%,21.1%,40.6%.All extracts showed inhibitory effect against test bacteria.It was observed that the inhibition of G+was stronger than G-,and the extracts had the best antibacterial activity to Staphylococcus aureus while the weakest to Aspergillus flavus.The antibacterial activity of the components decreased in the order:ethyl acetate extract>n-butanol extract>chloroform extract>petroleum ether extract>aqueous phase.The extracts were stable under ultraviolet radiation(UV)light and long term storage.The antibacterial activity of the extracts was weaker with the increase of pH value when the pH value≤8.[Conclusions]It is inferred that the antibacterial components in the extract of Pinus massoniana needles are widely distributed,and the components with medium polarity or above are the main antibacterial components.
文摘为提高层合板损伤检测的准确性与灵敏度,基于聚偏二氟乙烯(polyvinylidene fluoride,PVDF)梳状换能器激发的零群速度(zero group velocity,ZGV)Lamb波,提出了一种层合板损伤的检测方法。采用二维时域有限元方法,研究了PVDF梳状换能器对零群速度Lamb波的激励,通过改变层合板中铝层杨氏模量来表征不同的损伤程度,分析了PVDF梳状换能器电压响应特性与层合板损伤程度之间的关系。结果表明:采用PVDF梳状换能器能够有效激励零群速度Lamb波,并获得层合板内部的状态信息。随着损伤程度的增加,PVDF梳状换能器响应的零群速度共振峰频域幅值随着铝层杨氏模量的减小而显著减少,进而灵敏地评价层合板损伤变化。研究结果说明优化设计的PVDF梳状换能器在零群速度Lamb波的激发与接收性能上都具有优越性,能够有效检测层合板损伤情况。
基金National Key R&D Program of China(No.2021YFE0107800)National Science Foundation for Distinguished Young Scholars(No.52325805)CCCC Academician Special Scientific Research Funding Project(No.YSZX-03-2021-01-B).
基金This study was supported by National Key Research and Development Program of China(No.2018YFA0605601)National Natural Science Foundation of China(No.42077417 and41671042).
文摘The Tongbai Mountains is an ecologically sensi-tive region and the northern boundary of Pinus massoniana Lamb.To analyze the effect of different microenvironments on tree growth response to climate factors,we developed standard chronologies for earlywood width(EWW),late-wood width(LWW),and total ring width(TRW)of P.massoniana at two sampling sites on slopes with different orientations,then analyzed characteristics of the chronolo-gies and their correlations with climate variables from five stations in the region and with a regional normalized differ-ence vegetation index(NDVI).Statistical results showed that the TRW/EWW/LWW chronology consistency and charac-teristics(mean sensitivity,signal to noise ratio,expressed population signal)for trees growing on the southeastern slope were much higher than for trees on the northeastern slope.Correlations indicated that temperature in current March and August has a significant positive effect on TRW/EWW/LWW formation,and the effect on the northeastern slope was weaker than on the southeastern slope.Compared to temperature,precipitation has more complicated effects on tree growth,but the effect on the northeastern slope was also generally weaker than on the southeastern slope.Step-wise linear regression analyses showed that temperature in August was the main limiting factor at the two sampling sites.Similarly,the response of tree growth on the southeast-ern slope as determined by the NDVI is better than on the northeastern slope,and the TRW/EWW/LWW chronologies for the southeastern slope explained over 50%of the total NDVI variances in June.Overall,the results indicate that the difference in the climate response of P.massoniana at two sampling sites is clearly caused by differences in the microenvironment,and such differences should be properly considered in future studies of forest dynamics and climate reconstructions.