Adaptive responses of Acer ginnala, Pyrus ussuriensis and Prunus davidiana seedlings to soil moisture stress

One-year-old seedlings of Amur maple (Acer ginnala Maxim), Ussurian pear (Pyrus ussuriensis Maxim) and David peach (Prunus davidiana Carr) were planted in pots in greenhouse and treated with four different soil moisture contents (75.0%, 61.1%, 46.4% and 35.4%). The results showed that net photosynthesis rate (NPR), transpiration rate (TR) and stomatal conductance (Sc) of seedlings of the three species decreased with the decease of soil moisture content, and Amur maple seedlings had the greatest change in those physiological indices, followed by Ussurian pear, David peach. Amur maple and Ussurian pear seedlings also presented a decrease tendency in water use efficiency (WUE) under lower soil moisture content, whereas this was reversed for David peach. Under water stress the biomass allocation to seedling root had a significant increase for all the experimental species. As to root/shoot ratio, Amur maple seedlings had the biggest increase, while David peach had the smallest increase. The leaf plasticity of Amur maple seedlings was greater, the leaf size and total leaf area decreased significantly as the stress was intensified. No significant change of leaf size and total leaf area was found in seedlings of Ussurian pear and David peach. It was concluded that Amur maple was more tolerant to soil moisture stress in comparison with David peach and Ussurian pear.

长白山白桦(Betula platyphlla)纯林和白桦山杨(Populus davidiana)混交林凋落物的分解

采用交互分解实验,研究长白山白桦叶片和白桦、山杨与水曲柳混合叶片在白桦纯林和白桦山杨混交林内的分解过程。两年的分解实验结果表明,两种类型叶片均存在一个快速分解阶段和一个慢速分解阶段,森林类型和凋落物类型对凋落物分解率的影响在快速分解阶段不显著而在慢速分解阶段显著;混交林内的环境促进了凋落物分解和养分元素释放;在同一林型内,底物质量高的混合叶片其分解率和养分元素释放率均大于底物质量低的白桦叶片;凋落物的底物质量在一定程度上可以抵消森林类型对凋落物分解的影响;白桦山杨混交林混合叶片分解速率和养分元素释放率要显著大于白桦纯林内的白桦叶片,说明白桦山杨混交林的物质循环速度和养分元素供应能力要显著大于白桦纯林。

半干旱黄土丘陵区天然次生灌木山桃(Prunus davidiana)与山杏(Prunus sibirica L.)叶片气体交换参数日动态差异

以半干旱黄土丘陵区5年生天然次生灌木山桃(Prunus davidiana)及山杏(Prunus sibirica L.)作为研究材料,系统比较了两树种叶片气体交换参数的日变化特征,分析了其光合作用和蒸腾作用与环境因子的关系。结果表明:山桃叶片气体交换参数日变化特征与山桃有所差异,山桃除蒸腾速率(Tr)外其它生理参数呈单峰曲线,山杏的日变化类型均呈双峰曲线。两树种光合速率(Pn)在下午明显下降,其原因主要是受到非气孔限制。山桃Pn的日均值((7.64±3.69)μmo.lm-2.s-1)比山杏((5.29±2.97)μmo.lm-2.s-1)高出46%,Tr的日均值((2.21±1.02)mmo.lm-.2s-1)比山杏((1.58±0.57)mmo.lm-.2s-1)高出40%左右,水分利用效率(WUE)的日均值相差不大,分别为(2.89±1.52)μmo.lmmol-1,(2.54±1.37)μmo.lmmol-1。多元回归及相关分析表明,影响光合作用与蒸腾作用的最重要因子是光合有效辐射强度,其次是大气CO2浓度;光合作用与蒸腾作用参数之间也有明显的相关性。结论:山桃与山杏表现出具有较高光合速率,较低蒸腾速率和较高水分利用效率的生理特征,因而在半干旱黄土丘陵区都有较好引种栽培与开发利用潜力。

Contribution of aboveground litter to soil respiration in Populus davidiana Dode plantations at different stand ages

Soil respiration from decomposing aboveground litter is a major component of the terrestrial carbon cycle. However, variations in the contribution of aboveground litter to the total soil respiration for stands of varying ages are poorly understood. To assess soil respiration induced by aboveground litter, treatments of litter and no litter were applied to 5-, l0-, and 20-year-old stands of Populus davidiana Dode in the sandstorm source area of Beijing-Tianjin, equations were applied to China. Optimal nonlinear model the combined effects of soil temperature and soil water content on soil respiration. Results showed that the monthly average contribution of aboveground litter to total soil respiration were 18.46% ± 4.63%, 16.64% ± 9.31%, and 22.37% ± 8.17% for 5-, 10-, and ao-year-old stands, respectively. The relatively high contribution in 5- and 20-year-old stands could be attributed to easily decomposition products and high accumulated litter, resoectivelv. Also. it fluctuated monthly for all stand ages due to substrate availability caused by phenology and environmental factors. Litter removal significantly decreased soil respiration and soil water content for all stand ages （P 〈 0.05） but not soil temperature （P 〉 0.05）. Variations of soil respiration could be explained by soil temperature at 5-cm depth using an exponential equation and by soil water content at lo-cm depth using a quadratic equation, whereas soil respiration was better modeled using the combined parameters of soil temperature and soil water content than with either soil temperature or soil water content alone. Temperature sensitivity （Q10） increased with stand age in both the litter and the no litter treatments. Considering the effects of aboveground litter, this study provides insights for predicting future soil carbon fluxes and for accurately assessing soil carbon budgets.

Improved salt tolerance of Populus davidiana × P. bolleana overexpressed LEA from Tamarix androssowii

Development of transgenic plants with tolerance to environ- mental stress is an important goal of plant biotechnology. （LEA） proteins accumulate in seeds dur- ing late embryogenesis, where they protect cellular membranes and macromolecules against drought. In this work, we transferred the Tamarix androssowii LEA gene into hybrids of Populus davidiana xp. bolleana. We compared relative rates of height growth, chlorophyll fluo- rescence kinetic parameters, and leaf Na＋ levels of six TaLEA-containing lines with non-transferred plants （NT）, all grown under 0.8% NaC1 stress condition. Survival percentages of transgenic lines were all higher than for NT controls after rehydration and the sur- vival percentage of SL2 was five-fold higher than for NT controls. Seed- ling height increased 48.7% in SL2 （from the onset of induced stress to the end of the growing season）, 31% more than for the NT controls. Chlorophyll fluorescence kinetic parameters showed a marked increase in photosynthetic capacity in SL2 and SL5. Na＋ levels in young leaves of transgenic lines were lower than in control NT leaves, but higher in yel- low and withered leaves, indicating improved salt tolerance in transgenic lines.

Propagation techniques on root turion sprout browse of Populus davidiana Dode

The root segments selected from dominant trees of Populus davidiana Dode were taken as reproductive material and were buried in different depths to carry out the reproduction of root turion sprout. The affecting factors of germination rate, survival rate, and height growth for cutting wood of root sprout were comparatively analyzed. The results showed that the best suitable substrate for burying root is pearlite, with a germination rate of 15.16%. 3-4-cm root segments has the highest rate of germination (12.4%). The mixture of sand and soil (2:1) is the best cutting substrate, with a survival rate of 81.3%, while as to height growth of cutting wood, the mixture of turfy and soil (1:1) is the best. The cutting woods selected from different positions of stem show difference in height growth. The cutting wood from top stem is higher obviously than those from middle or low stem.

Effects of Water State of Soil on Ecological Boundary of Leaf Surface of Populus davidiana

The effect of water state of soil on eco-boundary over leaf surface was disscussed by takingPopulus davidiana as experimental material. The results show that to change soil water state by some methods was to adjust and control the forming quality of eco-boundary in fact. The plant in good water condition must be accompanied by thinner eco-boundary. This eco-boundary is beneficial to exchange and flow of the substances between plant and environment.

A new diterpenoid from the stem bark of Populus davidiana

A new diterpenoid, named populusol A （1）, was isolated from the methanolic extraction of the stem bark of Populus davidiana. The structure was elucidated on the basis of extensive 1D and 2D NMR as well as HRFAB-MS spectroscopic analysis.

A new salicin derivative from the stem bark of Populus davidiana

Phytochemical study on the BuOH-soluble fraction of the stem bark of Populus davidiana resulted in the isolation of a new salicin derivative （1）, named davidianoside. The structure was elucidated on the basis of extensive physicochemical and spectroscopic analyses.

FRACTAL DIMENSION OF POPULUS DAVIDIANA LEAF SURFACE ROUGH EXTENT

The rough extent of leaf surface may be described by protruding of waxes which like as wart and of stomatal aperture and of width of the cuticular ledge around guard cells. Because the morphology of the leaf surface has obviously similar itseIf, so one can use the theory of the fractal dimension to deal with the problems of leaf surface rough. The paper studied the rough extent and the result showed: with the leaf growing up, the waxes accumulate more and more, the leaf surface is more rough and the dimension is larger. The dimension D which indicates the rough extent of warts protruding is about 2. 10-2.20 on the above epidermis; On the beneath epidermis the dimension D of stomatal opening protruding is about 2.00-2.24, Maximum width L of cuticular ledge is about 1.0-7.4μm.

Promotion of biomass, photosynthesis, and root growth of seedling biomass, photosynthesis, and root growth of Populus davidiana × P. bolleana by two species of ectomycorrhizal fungi

The addition of ectomycorrhizal fungi(ECMF),beneficial rhizosphere microorganisms,to the soil can pro-mote plant growth and resistance.Here,Populus davidi-ana×Populus bolleana tissue culture seedlings were grown for 3 months in soils inoculated with one of the species,then seedlings were assessed for mycorrhizal colonization rate and growth,physiological and root traits.Suillus luteus and Populus involutus each formed ectomycorrhizal associa-tions with the seedlings.Seedling height,ground diameter,biomass,and leaf area were significantly greater after treat-ment with ECMF than in the non-inoculated controls.Treat-ment improved all physiological and root variables assessed(chlorophylls and carotenoids,cellulose,and soluble sugars and proteins;root length,surface area,projected area,mean diameter,volume,number of root tips).Seedlings inocu-lated with S.luteus outperformed those inoculated with P.involutus.

兰州盆地渐新统化石山杨(Populus davidiana Dode)数据化初探

本文试用平台式扫描仪和GetData Graph Digitizer软件相结合的方法,对产于兰州盆地渐新统二维形态的化石山杨(Populus davidiana Dode)叶片进行数字化,获得其叶相的主要基本参数数据。然后用Golden Software Grapher软件对数据进行检验,重建的化石形态与原叶片宏观特征吻合程度很好。这表明:对于二维形态的叶化石,利用相关软件获取图形数据是一种可行的方法,这也可为叶片化石形态定量化分析和重建3D化石图像用于博物馆展览和科普宣传提供基础的数据。

白城山新1号杨增殖培养试验

为筛选出白城山新1号杨最佳增殖培养基配方,本试验采用正交试验法经组织培养对其进行繁育,以MS培养基为基础配方,将6-BA质量浓度、NAA质量浓度、大量元素含量、蔗糖质量浓度分别设置5个水平进行试验。经回归分析,确定MS+6-BA 0.30 mg·L^(-1)+NAA 0.05 mg·L^(-1)+蔗糖20.00 g·L^(-1)为白城山新1号杨组培增殖培养基优化配方。

红翅拟柄天牛在红果树上的空间危害特征

为明确红翅拟柄天牛Cataphrodisium rubripenne(Hope)对红果树Stranvaesia davidiana的危害特性,调查该天牛的排粪孔、羽化孔、蛹室和蛀道在红果树上的空间分布特征。结果表明:在云南省富源县,红翅拟柄天牛排粪孔主要分布在高度150 cm以下树干和直径5~10 cm枝干,在树干阴面的数量显著高于阳面;羽化孔集中分布于高度150 cm以下树干和直径15 cm以下枝干,且枝干阳面羽化孔数显著多于阴面。排粪孔和羽化孔数量随树干高度增加而减少,与树干高度显著负相关。蛹室位于羽化孔上方,距离羽化孔的距离为(18.89±5.04)cm。蛀道主要集中在高度0~150 cm树干和直径5~10 cm的枝干,蛀道数量和大小与树干高度显著负相关,与枝干直径显著正相关。研究结果可为红翅拟柄天牛的精准林间防治提供理论参考依据。

杨树白粉病菌鉴定及宿主叶片的生理反应

为研究山新杨白粉病的病原菌种类以及病原菌侵染后宿主叶片的生理反应,观察了山新杨白粉病菌分生孢子的形态特征及特异性入侵结构,统计不同介质分生孢子的萌发情况,测定5个不同感病时期(健康、早期、中期、晚期、末期)山新杨叶片的过氧化氢酶(CAT)、过氧化物酶(POD)、超氧化物歧化酶(SOD)活性和丙二醛(MDA)的质量摩尔浓度变化,应用分子生物学分析的方法鉴定山新杨白粉菌病原。结果表明:山新杨白粉病菌分生孢子萌发时产生裂瓣状附着胞,并且萌发时不受介质面影响。感病前后,山新杨叶片内的生理生化指标变化显著,其中超氧化物歧化酶、过氧化物酶以及过氧化氢酶活性均呈先升高后下降趋势,丙二醛质量摩尔浓度则呈不断上升趋势。说明侵染前期,由于白粉病菌胁迫,叶片活性氧上升,抗氧化酶活性与丙二醛质量摩尔浓度升高;随着感病程度加重,叶片清除活性氧的能力下降,抗氧化酶活性降低,丙二醛质量摩尔浓度升高。通过ITS序列比对与系统发育进化树分析,可认为山新杨白粉病病原菌为Erysiphe adunca(Wallr.)Fr.var.adunca。

黄枝油杉种苗质量分级标准研究

黄枝油杉由于其分布区狭窄,繁殖速度慢,资源少,是国家二级保护植物。为了更好地保护其种质资源,通过实验研究种苗质量分级标准。分别对2年生和4年生的黄枝油杉种苗性状特征描述,以地径和株高作为主要分级标准代表,运用Excel 2003和SPSS 26.0对种苗特征数据进行统计学相关分析、主成分分析、K均值聚类分析,将其种苗分别2年生和4年生分别分成了三级。2年生一级株高>20 cm,冠幅>11 cm,地径≥0.10 cm;4年生一级株高>127 cm,冠幅>56 cm,地径≥0.80 cm。2年生二级株高14~20 cm,冠幅8~11 cm,地径≥0.10 cm;4年生二级株高96~127 cm,冠幅38~56 cm,地径≥0.80 cm;2年生三级株高<14 cm,冠幅<8 cm,地径≥0.10 cm;4年生三级株高<96 cm,冠幅<38 cm,地径≥0.80 cm。

春榆中总黄酮提取工艺优化

目的:优化春榆中总黄酮的提取技术后,利用紫外-可见光谱法(UV-Vis)检测春榆中总黄酮的含量。方法:春榆总黄酮提取率的效果以温度,乙醇体积分数和时间通过正交试验法,确定最优的春榆提取技术,通过UV-Vis检测春榆中总黄酮含量。结果:确定以50%的乙醇、温度75℃、时间100 min为春榆总黄酮最优提取条件,故总黄酮提取率为9.69%。结论:乙醇回流提取法成本低廉、易操作,正交试验设计法优化春榆总黄酮提取工艺条件,简单易行、重复性佳,为春榆总黄酮的研究提供了一定参考依据。

黑龙江省山杨倍性调查分析

【目的】多倍体具有器官巨大性和抗逆性强等特点,筛选多倍体一直是获得林木优良品种的方法之一。山杨生长速度快,是土壤改良、防风固沙工程上的重要树种。因此,调查不同分布区的山杨倍性,对筛选优良杨树多倍体具有指导意义。【方法】使用倍性分析仪和荧光原位杂交技术(FISH)对大兴安岭、伊春和牡丹江地区的山杨进行倍性分析。【结果】大兴安岭地区的31个山杨样品中存在6个三倍体植株。而伊春和牡丹江地区14和44个山杨样品均为二倍体植株。【结论】在大兴安岭地区存在天然的三倍体山杨。

PdbSPL28基因过量表达提高山新杨对叶斑病的抗性

【目的】SPL(SQUAMOSA promoter-binding protein-like)是植物特有的一类转录因子,对植物生长发育以及天然免疫反应至关重要。本研究通过在山新杨中过表达PdbSPL28基因,分析比较野生型和转基因山新杨在抗病方面的表型差异,探究PdbSPL28基因的生物学功能及其对杨树抗病性的影响,为深入解析该基因调控杨树抗病性的分子机制提供基础。【方法】利用同源克隆获得山新杨PdbSPL28基因完整ORF序列,并利用DNA人工合成技术对该基因ORF中的miR156作用位点进行序列改造,采用酶切、连接反应分别将改造前和改造后的PdbSPL28基因序列构建过表达载体;采用Gateway技术构建亚细胞定位载体,利用烟草叶片瞬时转化系统分析PdbSPL28蛋白亚细胞定位;利用农杆菌介导的叶盘转化法获得PdbSPL28基因过量表达的转基因山新杨,基于刺伤接种法和石蜡切片技术,观察野生型和转基因山新杨对2种间座壳属病原菌(Diaporthe nobilis和D.cercidis)的抗性差异及叶片解剖结构变化并测定病情指数;制备病原菌D.nobilis孢子悬浮液,接种野生型和2个过表达株系的离体叶片,在接种后不同时间点采集样品,通过液质联用方法检测茉莉酸含量变化。【结果】山新杨PdbSPL28基因ORF全长1341 bp,序列中含有1个miR156作用位点;PdbSPL28蛋白含有保守的SBP结构域,定位于细胞核。对PdbSPL28基因ORF中miR156作用位点改造后,成功获得6个该基因过量表达的转基因株系。与野生型相比,PdbSPL28过表达山新杨对2种间座壳属病原菌的抗性明显增强。茉莉酸测定结果显示:在接种前,PdbSPL28过表达株系叶片中茉莉酸含量高于WT;但在接种96 h时,过表达株系茉莉酸含量极显著低于WT。【结论】对miR156作用位点进行序列改造,可以提高获得PdbSPL28基因过量表达转基因山新杨的概率;PdbSPL28基因过表达可以提高山新杨对间座壳属真菌引起的叶斑病抗性,茉莉酸信号途径可能在过表达株系响应D.nobilis侵染过程中发挥重要作用。

山新杨谷胱甘肽S-转移酶编码基因PdbGSTU功能分析

【目的】本研究旨在通过分析山新杨谷胱甘肽S-转移酶编码基因PdbGSTU的抗病功能,为林木抗性育种提供基因资源与抗性种质。【方法】克隆PdbGSTU基因序列并对其进行生物信息学分析,利用荧光定量PCR技术分析该基因的组织特异性表达及植物激素诱导下的表达模式。利用转基因技术获得山新杨的过/抑制表达PdbGSTU基因植株,通过观察比较接种细链格孢菌后各植株叶片的表型和病斑面积,验证该基因的抗病功能;同时测定接种病原菌前后,野生型和转基因山新杨植株内过氧化氢含量和抗氧化相关酶活性。【结果】(1)山新杨PdbGSTU基因开放阅读框全长753 bp,编码氨基酸250个,对应的蛋白质相对分子质量为29.01 kDa,为稳定的酸性亲水蛋白,定位于细胞质中;系统进化分析显示,PdbGSTU蛋白与银中杨的蛋白KAJ6918316亲缘关系最近;启动子序列分析显示,PdbGSTU基因启动子序列含多种响应植物激素和逆境胁迫的顺式作用元件。(2)RT-qPCR结果显示,PdbGSTU基因在山新杨顶芽表达量最高,在其根部表达量最低,且该基因受茉莉酸甲酯、水杨酸和1-氨基环丙基-1-羧酸3种植物激素诱导,均上调表达。(3)接种细链格孢菌后,野生型和抑制表达PdbGSTU基因植株的叶片上,病斑面积分别为6.42和16.46 mm2,而过表达PdbGSTU基因的植株叶片上,少部分接种点出现明显病斑,其余接种部分仅出现褪色。【结论】PdbGSTU正向参与山新杨对细链格孢菌侵染的抵御过程,可通过清除活性氧提高杨树对病原菌的抗性。