两种藤本植物叶片性状及相关性对季节的响应

研究通过对两种藤本植物叶片的叶面积、比叶面积、叶厚度、气孔参数和叶脉密度的测定来分析不同季节下植物叶片的性状差异以及其性状之间的联系,为探讨植物叶片性状对环境适应的可塑性提供理论基础,同时也为藤本植物在园林中的应用提供依据。结果表明:(1)两种藤本植物叶片各性状随着季节变化呈现显著差异(P<0.5),季节变化对五叶地锦的影响大于爬山虎。两种植物的叶面积和叶厚度均夏季为最高;五叶地锦叶片气孔长度和气孔密度随季节变化先减小后增大;爬山虎叶片气孔长度随季节变化逐渐增大,气孔密度先减小后增加,春季气孔密度最大;叶脉密度均为春季最大,夏季和秋季逐渐降低。(2)两种植物叶片各性状之间存在一定的联系,但是显著性因品种和季节变化而不同。     

橡胶树无性系苗期生长和叶片表型性状比较分析

比较分析了云南河口和景洪2个试验点橡胶树无性系生长和叶片表型性状的差异,旨在揭示不同地理环境下橡胶树无性系苗期生长和叶片性状的表型可塑性。以9个橡胶树无性系苗木为试材,分别测定了2个试验点内苗木的茎粗、株高、叶蓬数、叶面积、叶周长、叶长、叶宽、长宽比、比叶面积和叶片组织相对含水量。结果表明,参试的9个无性系在单个试验点内生长和叶片性状等10个指标差异均达到极显著水平(P0.01)或显著水平(P0.05);而2个试验点间茎粗、株高、叶长、叶周长和长宽比差异达极显著水平(P0.01),叶蓬数、叶面积、叶片相对含水量和比叶面积差异达显著水平(P0.05),叶宽差异未达到显著水平;河口试验点苗木的茎粗、株高、叶蓬数、叶面积、叶周长、叶长及长宽比均大于景洪试验点,而比叶面积和叶片相对含水量则小于景洪试验点。在可塑性方面,河口试验点较景洪试验点生长量更大,叶片更长、更大,其中614和621两个无性系生长可塑性更强,272、551、553和621号等无性系在叶面积、叶长和叶周长等方面可塑性更强。相关性分析表明,2个试验点苗木株高均与叶长和叶周长呈显著正相关,而与叶蓬数关系不显著;代表叶片大小的10个叶片性状在2个试验区内均呈显著正相关。系统聚类综合评价表明551、614和624号3个无性系在2个试验点生长表现较好、叶片较大。     

胡杨叶功能性状差异及其与树形因子的关系

叶片是植物光合作用的主要场所,其生理变化可反映不同生境下植物适生策略。探究塔里木河下游不同生长阶段的胡杨叶功能性状差异及其与树形因子的关系,以期为荒漠河岸林资源保护提供理论依据。结果表明:筛选的10个叶功能性状指标存在不同程度变异,变异系数介于10.7%～39.6%之间;其中叶干重变异系数最大,叶片厚度变异系数最小。幼树、中树、成树和老树叶功能性状间均存在相关性,即比叶面积与叶干物质含量、叶组织密度、叶面积、叶鲜重、比叶重呈极显著负相关(P<0.01),与叶片厚度呈极显著正相关(P <0.01)。树形因子对叶功能性状变异的共同解释量为79.33%,其中,枝下高、树高和冠幅是叶功能性状变异的主要影响因素,而枝下高对叶功能性状的正效应最为明显。总之,树形因子对胡杨叶功能性状的影响显著,不同生长阶段的胡杨通过叶片多个功能性状的协调和权衡分配来适应荒漠恶劣的生态环境。     

干旱胁迫对麻疯树幼苗抗氧化代谢的影响

采用盆栽控水的方法,研究了不同程度干旱胁迫下麻疯树幼苗叶片相对含水量（LRWC）、质膜透性、相对电导率（REC）、丙二醛（MDA）含量及抗氧化酶活性的变化。结果表明,麻疯树幼苗叶片相对含水量随胁迫时间的增加呈极显著（P〈0．01）下降趋势;相对电导率、丙二醛含量随胁迫时间的增加而呈极显著（P〈0．01）增加趋势,胁迫初期和中期二者增加幅度相对较小,胁迫后期急剧增加;超氧化物歧化酶（SOD）活性随胁迫时间的增加而持续升高,过氧化物酶（POD）活性和过氧化氢酶（CAT）活性随胁迫时间的增加呈先升高后下降的趋势,在W7（干旱35d）时POD和CAT活性达到最大值。     

日本栗叶面积与叶片生物量计算方法的初步研究

以6年生日本栗品种＂辽栗10号＂与＂大峰＂为试材,对其叶长、叶宽、单叶面积、单叶干重、冠幅、冠高、单株叶片生物量进行了测定。研究不同品种间叶片长宽比值和比叶面积的差异性,叶片长、叶宽和叶片长宽乘积与单叶面积的相关性以及冠幅、冠高与单株叶片生物量的相关性。结果表明：不同品种间叶片长宽比、比叶面积均无显著差异;对日本栗叶长、叶宽、叶片长宽乘积与单叶面积进行一元回归方程拟合,决定系数与修正决定系数均达极显著水平（P〈0.0001）,其中以叶片长宽乘积与单叶面积的一元二次回归方程回归效果最好,决定系数达0.987 9,修正决定系数达0.987 7;单株叶片生物量与冠幅面积和冠高的二元线性回归关系达极显著水平（P〈0.0001）,决定系数达0.997 2,修正决定系数达0.996 4。在生产上,可以通过测量冠幅面积、冠高计算出单株叶片生物量和叶面积指数,该方法操作简单,具有较高应用价值。     

鄂尔多斯6种植物叶片功能性状比较

以鄂尔多斯6种植物为研究对象,分别测定了叶面积(LA)、叶厚度、叶绿素含量(SPAD)、比叶面积(SLA)、叶干物质含量(LDMC)和叶片相对含水量(RWC)等叶功能性状,比较不同生活型叶片功能性状的差异性。结果表明:6种植物叶片通过减少叶面积、增加叶厚度和叶绿素含量来适应干旱环境,沙蓬、虫实等1年生植物的SLA显著高于柠条、沙柳、杨柴、油蒿等灌木(P0.05),而不同生活型LDMC的差异性表现为1年生植物显著低于灌木(P0.05),SLA与LDMC呈负相关关系。不同生活型植物叶片功能性状差异明显,1年生植物具有较强的获取资源和保持体内营养的能力,灌木能够较强地适应干旱环境。     

施肥对红锥幼苗叶功能性状的影响

对红锥(Castanopsis hystrix)2.5 a生幼苗进行施肥试验,测定和计算其叶形态功能性状单叶鲜质量、单叶干质量、叶长、叶宽、叶长宽比、单叶面积、比叶面积及水分功能性状叶相对含水率、干物质含量,并计算不同叶功能性状间的相关性,结果表明:施肥能够显著促进红锥幼苗叶片形态生长,增加叶片光截获能力;施肥能对红锥幼苗叶水分功能性状产生显著影响,干物质含量显著减少、相对含水率显著增加;施肥驱动不同功能性状间协同变化,多数叶功能性状间存在显著的相关性。     

格氏栲天然林植物功能性状与系统发育对林窗大小的响应

为探究植物功能性状与系统发育对不同林窗大小的响应,以格氏栲天然林为研究对象,采用简单线性回归探讨格氏栲天然林的叶功能性状和功能多样性随林窗大小的变化规律,并运用Pearson相关分析研究系统发育多样性与功能多样性的相关性,结合系统发育树和功能性状树揭示物种适应策略。结果表明：格氏栲天然林的比叶面积随林冠开度的增大而极显著减小(P<0.01),叶干物质含量随林冠开度的增大而显著降低(P<0.05),叶片氮含量随林冠开度的增大而极显著降低(P<0.01),叶片厚度随林冠开度的增大显著增大,叶绿素含量和叶片磷含量随林冠开度的增大显著升高(P<0.05)。增大林冠开度,格氏栲天然林的功能均匀度、功能分歧度和功能离散度具有显著降低的趋势（P<0.05）,而功能丰富度和Rao二次熵系数无明显的变化趋势。格氏栲天然林的系统发育结构和系统发育多样性与功能多样性之间的相关性较弱,仅系统发育多样性指数与功能丰富度呈现极显著正相关（P<0.01）。格氏栲天然林的叶功能性状均未检测到显著的系统发育信号（P>0.05）,且许多亲缘关系较远的物种具有功能相似性,表现出对外...     

北京市元宝槭和紫丁香叶片的功能性状和生态化学计量比及养分重吸收效率的城乡梯度差异

【目的】探究城市典型观赏树种养分限制沿城乡环境梯度的响应差异,以期为城市化下的城市森林观赏树种养分管理提供科学依据。【方法】分别于夏季和秋季沿北京城区–近郊–远郊梯度上采集典型观赏树种元宝槭和紫丁香的成熟叶和凋落叶,测定其6种叶片功能性状（叶鲜质量、叶干质量、叶面积、比叶面积、比叶质量、叶片含水率）和6种营养元素含量[（碳（C）、氮（N）、磷（P）、钾（K）、钙（Ca）、镁（Mg）],计算元素的化学计量比值和养分重吸收效率,比较元宝槭和紫丁香在叶片功能性状、生态化学计量特征以及养分重吸收效率上的差异;分析年均温度、年降水量、年均太阳辐射量等环境因子与元宝槭和紫丁香叶片功能性状、生态化学计量特征以及养分重吸收效率的相关性。【结果】叶片功能性状、营养元素含量及其化学计量比值对城市化有显著响应,且存在种间差异。沿城区到远郊梯度,元宝槭和紫丁香成熟期叶鲜质量、叶干质量、叶面积、比叶面积、叶片含水率整体呈上升趋势,而比叶质量降低。凋落期元宝槭叶片的叶鲜质量和叶干质量沿城乡梯度逐渐降低;紫丁香凋落叶的叶干质量和比叶质量在城乡梯度上呈先升高后降低的趋势,叶面积则逐渐变小。2个树种凋落叶的比叶面积均沿...     

顶坛花椒叶功能性状对经营措施的响应

为探明不同经营措施对顶坛花椒叶片形态性状、叶片养分含量和光合生理特征的影响,筛选喀斯特石漠化地区顶坛花椒种植最优的经营措施,以贵州省关岭县不同经营措施种植的顶坛花椒(Zanthoxylum planispinum var. dintanensis)人工林为研究对象,测定其叶片形态性状、生态化学计量和光合生理参数,研究其叶片功能性状对经营措施的响应。结果表明:与自然生长的顶坛花椒林相比,矮化密植和喷灌处理后,顶坛花椒的叶鲜重、叶饱和鲜重、叶面积、叶干重分别增加26%～31%、19%～29%、18%～23%、19%～33%;而叶组织密度、叶干物质含量在矮化密植+喷灌中均降低了7%,在矮化密植中分别升高4%和11%;矮化密植的比叶面积较自然生长减小12%,矮化密植+喷灌与自然生长无显著性差异,表明矮化密植与喷灌一定程度引起了顶坛花椒叶片形态性状的变化。矮化密植与喷灌显著降低了顶坛花椒叶片有机碳含量,但是对全氮和全磷含量的影响不明显。经营措施促使顶坛花椒净光合速率提高了77%～136%,矮化密植+喷灌对花椒光合速率的提升最明显。顶坛花椒叶片功能性状之间存在显著或极显著相关关系,其中形态性状与光...     

Effects of light and nutrients on seedlings of tropical Bauhinia lianas and trees

Lianas differ from trees in many life history characteristics, and we predicted that they are phenotypically more responsive to environmental variation than trees. We analyzed responsiveness to light and nutrient availability of five Bauhinia species (three lianas and two trees). Seedlings were grown in a shade house in two light regimes (5 and 25% of full sunlight) and two nutrient supply regimes (field soil and N fertilization equivalent to 100 kg ha(-1)), and important growth-related physiological and morphological plant parameters were measured. Light availability affected most of the measured variables, whereas N addition had only weak effects. In the four light-demanding species (two lianas and two trees), relative plant biomass growth rate increased and specific leaf area (SLA) decreased with increased light availability, whereas a shade-tolerant liana did not respond. Leaf N concentration and light-saturated photosynthetic rate per unit leaf area increased in response to increased irradiance or soil N in the light-demanding tree species and the shade-tolerant liana, but not in the two light-demanding lianas. The light-demanding lianas also had higher SLA and leaf mass ratio, resulting in a higher leaf area ratio (LAR) in high light, whereas the light-demanding trees did not. Across all treatments, mean plasticity indices of physiological and morphological traits, and all traits combined were similar among the studied species. Plasticity was higher in response to light than to N, indicating that light is the main factor controlling seedling responses of the studied species. Although lianas and trees did not differ in mean plasticity in response to light and N, the light-demanding lianas were phenotypically less plastic in LAR and in photosynthetic rates and biomass allocation than the trees. Light and N interacted in their effects on most physiological variables, but the consequences for relative growth rate differed little among species. We conclude that, contrary to our predictions, lianas were no more responsive to variation in light and N availability than trees.     

Family variation in gas exchange, growth and leaf traits of black locust half-sib families

Variations in several growth, gas exchange and leaf traits among greenhouse-grown black locust (Robinia pseudoacacia L.) seedlings from 11 half-sib families were investigated. Three weeks after germination, early growth rates ranged from a minimum of 1 cm d(-1) in the slowest growing family, to a maximum of 3 cm d(-1) in the fastest growing family. Significant family variation in net photosynthetic rate per unit leaf area (P(N)), stomatal conductance, chlorophyll content, height, diameter, stem dry weight and total dry weight was observed. Net photosynthetic rate declined with seedling age. Net photosynthetic rate per unit leaf area was significantly correlated (r < 0.4) with specific leaf area, total chlorophyll, root dry weight, foliage dry weight and total dry weight. The correlation coefficients were higher (r >/= 0.55) between P(N) x total leaf area and growth traits (height, stem dry weight, foliage dry weight and total dry weight). The study indicated that variation in leaf area among the families was one reason for the lack of a strong relationship between P(N) and growth.     

中国南北样带上栲属树种叶功能性状与环境因子的关系

以南北样带上9种主要栲属树种为研究对象,分析了栲属树种的主要功能性状与环境因子的关系.结果表明:样带上栲属树种的单位面积最大净光合速率与年平均气温成显著负相关(r=-0.413,P＜0.05),与年光合有效辐射呈显著正相关(r=0.457,P＜0.05),与年均降水量相关性不显著.比叶面积与年平均气温和年降水量均成显著的正相关(r=0.418,P＜0.05;r=0.334,P＜0.05).在叶片养分含量方面,栲属树种的叶氮含量、叶磷含量与年平均气温、纬度均无明显的相关性.     

Variations in leaf functional traits among plant species grouped by growth and leaf types in Zhenjiang,China

Leaf functional traits are adaptations that enable plants to live under various environmental conditions. This study aims to determine the differences in leaf functional traits among plants grouped by growth habit, leaf life span, leaf lifestyle, leaf form, and origin. Specific leaf area (SLA) of perennial or evergreen species was lower than that of annual or deciduous species because longer-lived leaves of perennial or evergreen species require more investment in structural integrity and/or defense against disturbances, especially with any resource constraint. SLA of large individuals was lower than that of small individuals. The low SLA in large individuals can improve their response to changing light and water conditions because increasing plant height is advantageous for light competition, but it can also impose a cost in terms of structural support and water transport. Petioles of plants with compound leaves were significantly longer than those of simple leaves because branching is expensive in terms of gaining height. SLA of plants increased with increasing invasiveness accordingly, and SLA of invasive plants was higher than that of their native congeners because invasive plants should invest more biomass on leaf growth rather than leaf structures per unit area to achieve a higher growth rate. Overall, variation in leaf functional traits among different groups may play an adaptive role in the successful survival of plants under diverse environments because leaf functional traits can lead to pronounced effects on leaf function, especially the acquisition and use of light. Plant species with different growth and leaf traits balance resource acquisition and leaf construction to minimize trade-offs and achieve fitness advantages in their natural habitat.     

油茶种间杂交叶表型的遗传变异分析

【目的】探究油茶杂交F1代叶片表型性状的分离规律和遗传变异特征。【方法】运用杂交F1代叶片质量性状香农-威尔多样性指数分析、数量性状离散描述及其相关性分析和聚类分析等数理统计法分析了攸县油茶×普通油茶‘华硕’种间杂交F1代47个单株的叶片表型(4个质量性状和12个数量性状)遗传多样性和遗传效应。【结果】1)叶表型的4个质量性状中,香农-威尔多样性指数的平均值为0.871,其中叶缘形态的多样性指数最高,为1.254;新叶颜色最低,为0.691。其中,叶形和叶背腺点有偏向母本的遗传趋势,而叶缘形态有偏离母本的遗传趋向。新叶颜色是绿色和红色趋近1︰1,分别是53.19%和46.81%,与母本相同的新叶颜色占46.81%,符合孟德尔遗传规律。2)12个叶片表型数量性状变异系数的平均值为17.75%,范围为9.55%~26.07%,经正态性检验后,发现其具有良好的正态分布趋势,符合多基因控制的数量性状遗传特征。12个叶表型数量性状在F1代的中亲优势率为-30.15%~25.93%。叶干质量、比叶重、叶型指数、叶长、叶面积和叶厚的中亲优势率为正,其中叶型指数和比叶重的平均值高于高亲值,叶鲜质量、叶宽、叶柄长、叶片含水率和叶顶角的中亲优势均为负,这些性状的平均值小于中亲值,其中叶鲜质量、叶宽和叶柄长趋中变异明显,存在于双亲之间,而叶片含水率和叶顶角的平均值小于低亲亲本,呈现出明显的趋小变异。3)16个叶片性状呈现错综复杂的相关性。4)聚类分析结果表明,聚类结果充分反映了各类群的综合特征。油茶种间杂交F1代在遗传距离为20.00处将其分为Ⅰ和Ⅱ类群。在遗传距离为10.0处,第Ⅰ大类群分为Ⅰ-a亚类和Ⅰ-b亚类。第Ⅰ大类群38个单株与母本攸县油茶聚在一起,形态表现与母本相似度更高,为偏母型。【结论】油茶种间杂交F1代叶表型性状变异丰富,其中12个数量性状表现出比较广泛的分离特征,4个质量性状均具有较丰富的多样性,这为下一步育种材料的利用提供了更广阔的空间。     

几种荒漠植物叶面积与叶干质量关系的研究

采用扫描图像与Photoshop图像处理软件结合的方法研究柽柳、柠条、红砂和珍珠的叶片投影面积与叶干质量之间的关系,结果表明：柽柳、柠条和红砂叶投影面积与叶干质量呈线性相关;红砂、柽柳、柠条在生长季单位叶面积所积累的叶干质量分别为（0．0840±0．0031）、（0．0610±0．0011）、（0．0366±0．0007）g/cm2,红砂和柽柳分别是柠条的2．30和1．67倍;珍珠的叶片是多浆汁叶,形状极不规则,不能利用日前的扫描仪计算出它的投影面积;柽柳在不同环境下生长时的叶片投影面积与叶干质量的关系均为线性相关且差异不显著,表明这种线形关系不受生长环境的影响。因此,可以用叶干质量代替叶面积来研究这些荒漠植物的光合作用特性。     

Relative importance of photosynthetic physiology and biomass allocation for tree seedling growth across a broad light gradient

Studies of tree seedling physiology and growth under field conditions provide information on the mechanisms underlying inter- and intraspecific differences in growth and survival at a critical period during forest regeneration. I compared photosynthetic physiology, growth and biomass allocation in seedlings of three shade-tolerant tree species, Virola koschynii Warb., Dipteryx panamensis (Pittier) Record & Mell and Brosimum alicastrum Swartz., growing across a light gradient created by a forest-pasture edge (0.5 to 67% diffuse transmittance (%T)). Most growth and physiological traits showed nonlinear responses to light availability, with the greatest changes occurring between 0.5 and 20 %T. Specific leaf area (SLA) and nitrogen per unit leaf mass (N mass) decreased, maximum assimilation per unit leaf area (A area) and area-based leaf N concentration (N area) increased, and maximum assimilation per unit leaf mass (A mass) did not change with increasing irradiance. Plastic responses in SLA were important determinants of leaf N and A area across the gradient. Species differed in magnitude and plasticity of growth; B. alicastrum had the lowest relative growth rates (RGR) and low plasticity. Its final biomass varied only 10-fold across the light gradient. In contrast, the final biomass of D. panamensis and V. koschynii varied by 100- and 50-fold, respectively, and both had higher RGR than B. alicastrum. As light availability increased, all species decreased biomass allocation to leaf tissue (mass and area) and showed a trade-off between allocation to leaf area at a given plant mass (LAR) and net gain in mass per unit leaf area (net assimilation rate, NAR). This trade-off largely reflected declines in SLA with increasing light. Finally, A area was correlated with NAR and both were major determinants of intraspecific variation in RGR. These data indicate the importance of plasticity in photosynthetic physiology and allocation for variation in tree seedling growth among habitats that vary in light availability.     

3个优势科树种叶功能性状及其关联特性

以小尺度范围内的木兰科、壳斗科和樟科各8种木本植物为研究对象,从分类单元科与种、功能群角度分析了叶功能性状特征及其关联性。结果表明:壳斗科树种的叶柄直径(1.08±0.22)和比叶面积(SLA)(90.87±25.35)显著低于樟科和木兰科,而樟科和木兰科之间差别不明显。叶含氮量在科间没有显著差异。从功能群比较,常绿树种比叶面积(90.10±23.15)显著低于落叶树种(134.65±27.77),但单位叶面积含氮量常绿树种(1.95±0.50)显著高于落叶树种(1.31±0.26)。在不同功能群中,叶面积与叶柄质量有很好的拟合直线关系。叶氮含量仅在常绿树种与其他叶性状有较好的拟合直线关系。叶性状相关性系数大于0.900的有:群落水平物种间叶面积与叶柄质量之间;功能群水平常绿树种叶面积与叶柄直径和叶柄质量间,落叶树种叶柄质量与叶面积和叶柄长间。其他叶性状间也表现不同程度的相关性,表明叶性状之间存在生长发育非同步也即异速生长现象。     

锥栗叶片生长过程及其生理动态变化

从2000年3月22日至4月27日,每隔5d取正在生长的锥栗叶片,测定其形态和生理指标.测定结果如下叶长、叶宽和叶面积的生长曲线为S型曲线,叶片的整个生长过程中形态上有一个快速增长期,即生长初期叶片的生长较缓慢,生长中期叶片迅速增长,生长后期又变慢,最后趋于稳定.在快速生长期,叶长的增幅比叶宽的增幅大;叶片生物量的生长曲线也为S型曲线,叶片鲜重增长的幅度比干重大.叶片生长过程中,叶绿素含量迅速上升,最后趋于稳定.生长初期可溶性蛋白质含量迅速降低,而后在一定值附近波动.过氧化物酶活性在生长初期和中期都保持在较高的状态,在生长后期过氧化物酶活性降至另一较低的状态.叶片含水量初期迅速上升,达到最高峰开始下降并趋于稳定,其变化曲线为一单峰曲线.     

南北样带温带区栎属树种幼苗功能性状的变异研究

植物功能性状由生境条件和遗传因素共同决定,田间控制实验能够揭示植物功能性状在种内和种间的变异程度.采集南北样带温带区8个地点6种栎属树种的种子,通过田间栽培试验,以均一环境下1年生幼苗为对象,研究比较种内及种间比叶重、单位叶面积光合速率、单位叶重量光合速率、总干物质含量和根冠比5种功能性状的变化差异,并且分析幼苗功能性状与种子性状的关系.结果发现:栎属树种种间幼苗的功能性状变异系数高于种内,并且种内功能性状的差异较小,种间差异性较大,而比叶重和叶片光合速率无论在种间还是种内,其变异率都较小;总干物质量和根冠比与种子质量显著相关,随种子质量增加幼苗的总干物质量和根冠比呈现增加的趋势,比叶重和叶片光合速率与种子质量的相关性较小.