Structural characteristics and eco-adaptability of heteromorphic leaves of <Emphasis Type="Italic">Populus euphratica</Emphasis>

The microstructural and ultrastructural traits of three kinds of typical leaves ofPopulus euphratica Olive, including lanceolate, broad-ovate and dentate broad-ovate leaves, were studied by using electron microscope and optical microscope. The resuits showed that with the leaves changing from lanceolate shape to dentate broad-ovate shape, their structure obviously tended to be xeromorph: developed palisade tissue, undeveloped spongy tissue, thick cutin layer and sunken stomas. The amount of mitochondria tended to be increased, and the shape of chloroplasts varied from regular spindle to irregular rotundity or oval. The leaves were covered with wax without cilium, and the stomas on the upper and lower epidermis of the leaves opened unevenly. The stomas on the lower epidermis were deeper than those on the upper epidermis under the scanning electron microscope. The results implied that the structural characteristics of the diversiform-leaves ofP euphratica are related to its eco-adaptability.     

Comparison of stomatal characteristics and photosynthesis of polymorphic Populus euphratica leaves

The leaf shapes of adult Populus euphratica vary from lanceolate to dentate broad-ovate. In order to find the mechanism regarding the ecological adaptation of the polymorphic leaves, the dentate broad-ovate, broad-ovate, and lanceolate leaves were chosen to study their stomatal and photosynthetic characteristics. It is observed that the stomas on the adaxial and abaxial epidermis of the same leaves open non-uniformly with similar densities. The stomatal densities are different among the three typical leaves, which decrease from broad-ovate to lanceolate leaves. Their stomatal sunken degree varied obviously, decreasing from broad-ovate to lanceolate leaves. The changes of the diurnal photosynthetic rate of the three typical leaves follow a single peak curve. The mean diurnal photosynthetic rates of these leaves rank from high to low as broad-ovate > dentate broad-ovate > lanceolate leaves. The light compensation points are similar in the three typical leaves, while the light saturation points vary obviously. The efficiency of solar energy conversion and potential activity of the PSII in the leaves differ significantly, with the dentate broad-ovate leaves the highest. The results suggest that their leaf shapes, anatomic structures, and photosynthetic characteristics change during the leaf development. __________ Translated from Scientia Silvae Sinicae, 2006, 42(8): 20–24 [译自: 林业科学]     

三种杨树叶片解剖结构特征分析

对2025杨及芽变品种中红杨、全红杨的叶片解剖结构通过电子显微镜扫描进行了观察和分析,结果表明3种杨树叶片由上、下表皮细胞、叶肉和叶脉四部分组成,在结构组成上差异较小,栅海比、CTR及SR比较上差异不显著。     

木兰科6属27种植物的叶片比较解剖学研究

应用石蜡切片技术和光镜观测方法,对采自云南昆明树木园的木兰科6属27种植物的叶片进行了比较解剖学研究。结果表明：（1）木兰科植物的叶片均为异面叶,由表皮、叶肉、叶脉构成;叶肉组织分化为栅栏组织和海绵组织,均具有圆形或近圆形油细胞;叶脉维管束韧皮纤维排列连续或不连续,成环状或轮状。（2）叶片下表皮细胞是否为具明显乳突的细胞和主脉维管束韧皮纤维细胞排列是否连续可明确区分木兰亚科和鹅掌楸亚科。（3）叶片厚度、上表皮厚度、海绵组织厚度可以对秃木兰属和鹅掌楸属进行明确区分,栅栏组织厚度、栅海比、油细胞大小和分布密度等余下性状则在数值上均存在属间重叠现象,不宜作为属间分类性状。（4）基于最大值和最小值进行的聚类结果与传统分类结果吻合度较基于平均值的聚类结果大,最大值和最小值比平均值更能表征研究对象。总之,表皮、下皮、叶肉组织和油细胞等部分叶片解剖学特征在探讨木兰科科下等级如亚科、部分属和部分种的分类地位时具有一定价值。     

6个油茶品种叶片解剖结构与耐寒性的关系

【目的】探讨油茶叶片解剖结构与耐寒性的关系,为油茶耐寒品种的选育和引种栽培提供参考依据。【方法】选取6个油茶品种为试验材料,利用常规石蜡切片技术和指甲油印迹法测量了9项叶片组织结构指标;通过聚类分析、相关分析对各项指标进行筛选,应用隶属函数法进一步综合评价6个品种的耐寒性。【结果】油茶为异面叶,上、下表皮细胞只有一层且排列紧密,气孔仅分布于下表皮,栅栏组织细胞为2~3层,叶片厚度差异显著。各品种间上表皮厚度、栅栏组织厚度及气孔密度的差异均达到极显著水平(P<0.01),叶片厚度、海绵组织厚度、下表皮、栅海比、组织结构紧密度、组织结构疏松度的差异均显著(P<0.05),影响油茶耐寒性的主要指标为上表皮厚度、海绵组织厚度、组织结构紧密度和气孔密度,6个品种的耐寒性由强至弱依次为:大别山1号>鄂油102号>赣州油8号>长林4号>岑软3号>鄂油54号。【结论】影响油茶耐寒性的主要叶片解剖结构指标是上表皮厚度、海绵组织厚度、组织结构紧密度和气孔密度,单独以某项指标分析时的差异较大,叶片作为完整的器官各个组织及其结构间必然相互影响,因此必须对其进行综合比较分析,这4项指标的差异在一定程度上可以反映不同品种油茶耐寒性的变化;但若要准确评价各个油茶品种的耐寒性,则需要同时考虑与其耐寒性相关的生理生化指标及其田间生长情况。     

生活污水对白骨壤和红海榄叶片指标及结构的影响

为了探讨2种红树植物叶片对生活污水环境的适应性,采用石蜡切片法和显微拍照法观察了白骨壤和红海榄2种红树植物的叶片结构。结果表明：污染区的白骨壤叶片的上角质层厚度、表皮层厚度、上内皮层厚度等均比无污染区的白骨壤大,而污染区的红海榄叶片则在下角质层厚度、上表皮层厚度、下内皮层厚度等指标上比污染区的红海榄显著增大,表明生活污水对红树植物的生长有一定的影响。     

四种含笑叶解剖性状与抗旱性的研究

对2年生乐昌含笑、金叶含笑、阔瓣含笑和深山含笑等4种含笑叶片组织解剖性状的测定与盆栽抗旱性观测表明:供试树种间叶解剖性状在叶片厚度、角质层厚度、栅栏组织厚度、海绵组织的厚度、栅栏组织与海绵组织的厚度比、叶片结构紧密度、叶片结构疏松度和气孔密度等指标有显著差异;上表皮和下表皮厚度结构指标差异不显著.叶片厚度、角质层厚度、栅栏组织厚度、栅栏组织与海绵组织厚度的比值、叶片结构紧密度和气孔密度等值越大的含笑,受旱危害愈轻,其抗旱性就越强.叶片厚度、尤其是角质层的厚度和海绵组织厚度是评价供试含笑抗旱性的重要解剖指标.依据叶解剖性状结构指标,并结合盆栽试验旱害观测,供试树种的抗旱性大小为:阔瓣含笑>深山含笑>金叶含笑>乐昌含笑.研究结果与大田容器苗受持续秋旱产生的旱害观测结果吻合,为苏南地区北移引种提供了科学依据.     

欧李叶表皮形态气孔指标与叶果矿质元素含量变化的关系

欧李(Cerasus humilis)是我国特有的一种野生果树资源,其果实中钙、铁等元素尤为丰富(曹琴等,1999),同时具有抗旱、耐寒、耐贫瘠、耐盐碱等特性,是生态建设和防风固沙的良好树种(姜英淑等,2009;李学强等,2009).研究表明:叶片是植物进化过程中对环境变化敏感且可塑性较大的器官,叶表皮形态结构随着环境的变化而形成自身相对稳定的遗传特征,叶片的气孔、表皮毛、角质层等结构与植物的抗逆性密切相关(李芳兰等,2005;李正理,1981;Bosabalidis et al.,2002;Sam et al.,2000;Mendes et al.,2001),而叶片气孔形态指标大小变化影响着植物的蒸腾、光合、呼吸等作用(潘瑞炽,2008).     

Hyperhydricity in apple: ultrastructural and physiological aspects

We studied the effects of hyperhydricity on subcellular ultrastructure and physiology of leaves during in vitro regeneration of apple plants. Morphological, anatomical and ultrastructural differences between healthy leaf tissues obtained from greenhouse-grown plants and healthy and hyperhydric leaves obtained from shoots raised from nodal shoot explants in a bioreactor were investigated by electron microscopy and confocal laser scanning microscopy. Compared with healthy leaves, hyperhydric leaves showed abnormal, often discontinuous development of the epidermis and cuticle. Stomata were malformed. The leaf lamina appeared thickened and was characterized by poor differentiation between the palisade and spongy mesophyll tissue. Hyperhydric leaves had a significantly lower chloroplast number per cell and chloroplasts showed reduced thylakoid stacking compared with healthy leaves. Hyperhydricity resulted in a general decrease in concentrations of reduced and oxidized pyridine nucleotides, reflecting a reduction in metabolic activity. The activities of antioxidant enzymes, such as superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase were higher in hyperhydric leaves than in healthy leaves, indicating that hyperhydricity was associated with oxidative stress. Chlorophyll fluorescence measurements provided evidence of oxidative damage to the photosynthetic machinery in hyperhydric leaves: photochemical efficiency of photosystem II, effective quantum efficiency and photochemical quenching were all lower in hyperhydric leaves compared with healthy leaves.     

荒漠植物白刺叶片气孔性状对模拟增雨的响应

为研究荒漠植物气孔性状对气候变化的响应以及对植物固碳能力的影响,根据内蒙古磴口多年平均降水量和植物生长规律,设计2个增雨时段(生长季前期与后期),每个时段设计2个增雨梯度(50%与100%),对天然白刺灌丛进行增雨实验,利用数码图像显微镜处理系统,研究叶片气孔大小、气孔密度及气孔导度等气孔性状对增雨的响应。结果表明:与对照相比,各增雨处理可以增加气孔长度、宽度与气孔导度,但孔密度减小,且叶片下表皮密度大于上表皮。相同增雨季节,100%处理对气孔大小、气孔密度及气孔导度的影响均高于50%处理,2个梯度间差异不显著;气孔大小与气孔导度对生长季前期增雨响应更敏感,气孔密度对不同生长季节增雨响应不明显;气孔性状之间存在一定的协调性。在未来降雨增加的条件下,荒漠植物可以通过改变气孔性状(扩大气孔)通路来提高固碳能力。     

Sclerophylly and leaf anatomical traits of five field-grown olive cultivars growing under drought conditions

Leaf-level morphological and structural adaptations to reduce water loss were examined in five olive (Olea europaea L.) tree cultivars (Arbequina, Blanqueta, Cobran?osa, Manzanilla and Negrinha) growing under field conditions with low water availability. Leaf measurements included leaf tissue thickness, stomatal density, leaf area, leaf mass per unit area, density of leaf tissue, relative water content, succulence, water saturation deficit, water content at saturation and cuticular transpiration rate. We found considerable genotypic differences among the cultivars. Negrinha, Manzanilla and Cobran?osa had more morphological and structural leaf adaptations to protect against water loss than the other cultivars. Manzanilla and Negrinha enhanced their sclerophylly by building parenchyma tissues and increasing protective structures like the upper cuticle and both the upper and lower epidermis. Cobran?osa exhibited good protection against water loss through high density of foliar tissue and by thick cuticle and trichome layers. Compared with the Negrinha, Manzanilla and Cobran?osa cultivars, Arbequina leaves had a thinner trichome layer, implying that the leaves were less protected against water loss; however, the development of smaller leaves may reduce water loss at the whole-plant level. Among cultivars, Blanqueta had the largest leaves and some anatomical traits that may lead to high water loss, especially from the adaxial surface. The mechanisms employed by the cultivars to cope with summer stress are discussed at the morpho-structural level.     

忍冬和华南忍冬叶表皮扫描电镜观察及其生态适应性研究

利用扫描电镜观察了忍冬(Lonicera japonica Thunb)和华南忍冬(Lonicera confus)叶表皮形态特征,观察指标包括:气孔器、表皮毛、表皮细胞等。结果表明:气孔仅分布在下表皮,气孔器呈无规则型散生;上表皮细胞的垂周壁呈沟槽状下陷;下表皮密被表皮毛(包括腺状毛和非腺毛),同时还分布有瘤状的草酸钙簇晶。为进一步证明这种瘤状结构是否为草酸钙簇晶,作者发现利用Fluo-3/AM(钙离子荧光指示剂)处理的活体叶片在激光共聚焦显微镜下能够发出强烈的荧光。此外,通过电子探针对瘤状物进行分析,发现其元素组成为C、O、Ca。上述叶表皮构造特征,有利于减少植物体水分散失,还有助于植物适应富钙的石灰土,从而适应我国西南岩溶区特殊的干旱、富钙的环境。电镜观察结果表明,在忍冬叶上表皮中脉处有呈线状分布的腺状表皮毛,而华南忍冬叶上表皮则无表皮毛分布,这一微形态特征可以作为二者种间特异性差别,从而为二者的合理区分提供一定的依据。图13表2参30。     

叶面肥对油茶幼苗生长和生理特征影响的研究

以1a生出圃的油茶幼苗为材料研究不同浓度无机盐配比的叶面肥对油茶幼苗生长发育的影响,以便获得有利于油茶幼苗生长的叶面肥.在N、P、K肥的基础上,对硼酸、硫酸锌、钼酸钠进行L9(34)正交试验设计来配制叶面肥,喷施油茶幼苗叶片一段时间后测定幼苗的生长及其生理生化指标,对测定结果进行了极差分析和方差分析,并对优化的叶面肥进...     

12种金花茶组植物叶片的比较形态学研究

研究利用万深 LA-S 系列植物图像分析仪和扫描电子显微镜（SEM）分别对山茶属金花茶组下 12 个种进行叶片形态数量特征和表皮特征进行比较研究。植物图像分析结果表明,12 种金花茶属植物在 叶周长、叶面积、叶柄长、叶长、叶宽、叶厚、叶长宽比,以及叶鲜重和干重 9 个性状上差异均极显著, 9 个性状在相同种不同个体之间差异显著,说明金花茶组植物种间和种内的叶片形态上具有丰富的性状变 异,无法作为组下分类的依据,但为育种提供了良好的遗传基础。叶表皮形态观测结果表明, 12 个种的 叶片上表皮形态结构基本一致,无气孔分布,细胞均为不规则形,细胞间界限不清晰;12 个种的下表皮 均有气孔分布,并具腺点,但不同种的气孔形状和细胞垂周壁式样在一些种间存在着明显的差异,腺点 形态也各不相同,这些性状在种内较为稳定,可为金花茶组的分类提供参考依据。     

Accumulation of flavanols in yellowing beech leaves from forest decline sites

Beech leaves were sampled during two consecutive years from three sites characterized by forest decline. Both monomeric and oligomeric flavanols from green and yellowing leaves were determined quantitatively by reversed-phase, high-performance liquid chromatography (HPLC) combined with a chemical reaction detection technique (CRD). Yellowing leaves generally contained more than twice the quantity of flavanols than normal green leaves. The monomeric flavanols, epicatechin and (+)-catechin, comprised up to 80% of the total flavanol fraction. Histochemical staining with p-dimethylaminocinnamaldehyde was used to determine local deposition of flavanols, including insoluble oligomeric flavanols, in leaf tissues. The yellowing leaves stained intensely, whereas the green leaves stained lightly. Flavanol staining was strongest in the spongy parenchyma followed by the palisade cells. The upper epidermis stained more intensely than the lower epidermis. A 4-day treatment of small leaf pieces (5 x 5 mm) with 0.04 mM paraquat resulted in browning of the leaf pieces. The browning reaction was prevented when the paraquat treatment was carried out in the presence of 0.16 mM (+)-catechin, indicating an antioxidative property for this flavanol.     

云南省红河州石漠化治理树种叶的结构研究

通过石蜡切片和显微测量，研究了云南省红河州石漠化治理树种属内种间叶的结构及抗旱性的差异。结果表明：松属有2个指标存在差异，即表皮厚（马尾松-加勒比松〉细叶云南松）和下皮厚（加勒比松〉细叶云南松〉马尾松）；柏木属有2个指标存在差异，即总厚度和上表皮厚（均为墨西哥柏〉冲天柏）；按属有4个指标存在差异，即上角质层厚、下角质层厚、栅栏组织厚（均为赤桉〉直干桉）和海绵组织厚（赤桉〈直干桉）；金合欢属有6个指标存在差异，即总厚度、上表皮厚、下表皮厚、腹侧栅栏组织厚、背侧栅栏组织厚和贮水组织厚（均为肯氏相思〉大叶相思）。因此，如果仅从叶的结构来比较抗旱性，则松属中加勒比松〉马尾松〉细叶云南松；柏木属中墨西哥柏〉冲天柏；桉属中赤桉〉直干桉；金合欢属中肯氏相思〉大叶相思。     

杉木缺硼症的组织学和生理生化特性研究

为了了解缺硼杉木苗叶、茎组织内部变化情况和生理生化特性，对其进行了切片观察和生理生化指标测定．结果表明：缺硼病苗叶组织和整组织均发生显著变化，叶绿体超微结构受到破坏；病苗叶各叶绿素含量增加，蛋白质含量下降，脯氨酸含量上升，全株可溶性总糖含量不变，而新生组织可溶性总糖含量降低．     

Chlorophyll a fluorescence analysis along a vertical gradient of the crown in a poplar (Oxford clone) subjected to ozone and water stress

An experiment in open-top chambers was carried out in summer 2008 at Curno (Northern Italy) in order to study the effects of ozone and mild water stress on poplar cuttings (Oxford clone). In this experiment direct fluorescence parameters (JIP-test) were measured in leaves from different sections of the crown (L: lower; M: medium; U: upper parts of the crown). The parameters considered were calculated at the different steps of the fluorescence transient, and include maximum quantum yield efficiency in the dark-adapted state (F(v)/F(M)); the L-band, at 100?∝?s, that expresses the stability of the tripartite system reaction centre-harvesting light complex-core antenna; the K-band, at 300?∝?s, that expresses the efficiency of the oxygen-evolving complex; the J-phase, at 2 ms, that expresses the efficiency with which a trapped exciton can move an electron into the electron transport chain from Q(A)(-) to the intersystem electron acceptors; the IP-phase, which expresses the efficiency of electron transport around the photosystem 1 (PSI) to reduce the final acceptors of the electron transport chain, i.e., ferredoxin and NADP; and finally the performance index total (PItot) for energy conservation from photons absorbed by PSII to the reduction flux of PSI end acceptors. The main results are: (i) different dynamics were observed between leaves in the lower section, whose PItot decreased over time, and those in the upper sections in which it increased, with a dynamic connected to the leaf age; (ii) ozone depressed all the considered fluorescence parameters in basal leaves of well-watered plants, while it had little or no damaging effect on medium-level or upper-section leaves; (iii) PItot and IP-phase increased in upper leaves of plants subjected to ozone stress, as well as the net photosynthesis; (iv) water stress increased PItot of leaves in all levels of the crown. The results suggest that ozone-damaged poplar plants compensate, at least partially, for the loss of photosynthesis with higher photosynthetic rates in young leaves (in the upper section of the crown), more efficient to fix carbon.     

短梗大参解剖学特性及生态学意义

为给短梗大参的栽培和推广利用提供科学依据,以短梗大参种子萌发幼苗和2年生实生苗为试验材料,利用光学显微镜和扫描电镜对其根、茎和叶片的解剖结构及气孔进行了观测和分析。结果表明:短梗大参具有一般双子叶植物的解剖特征,其根、茎、叶表现出明显的喜湿阴特点:根毛稀少,根和茎木质部中导管数量较少,木质化程度也低,叶片角质层很薄,海绵组织较发达,栅栏组织和海绵组织比为0.44;气孔器近圆形,密度为98~116个/mm2,保卫细胞两端具有典型的"T"型加厚特征,气孔外围角质纹饰为条纹状隆起。     

火龙果不同月龄枝条的叶绿体超微结构及叶绿素荧光特性

为揭示发育过程中火龙果枝条光合特性变化的生理机制,给火龙果的高效栽培提供参考依据,研究了不同月龄火龙果枝条的叶绿体超微结构、叶绿素荧光参数及光合色素含量。分别采集1月龄(S1)、2.5月龄(S2)、3.5月龄(S3)、11月龄(S4)的火龙果枝条,测定枝条外观形态及其正背面的叶绿体超微结构、叶绿素荧光参数及光合色素含量等指标。结果表明,S1—S4月龄火龙果枝条的正面、背面均具有完整的叶绿体结构,随月龄增加,叶绿体中的淀粉逐渐增多。S3月龄火龙果枝条的实际光化学效率、光化学猝灭系数均达到峰值。S4月龄枝条的最大光化学效率、非光化学猝灭系数均明显降低。综上所述,S1—S3月龄火龙果枝条的光合机构发育成熟,光合能力增强,为枝条后期营养物质的快速积累提供了条件,之后枝条肉质厚度增加,使枝条由营养生长向生殖生长转化,进入结果期;S4月龄枝条光合能力减弱,易发生光抑制。