木本植物导管长度分布规律研究新方法

从理论上推导出以着色导管数计算导管长度的关系式,为注入颜料法测定植物导管长度分布规律了理论基础,并推导了导管长度分布规律,以及着色导管数与样品长度关系。以香梓、梧桐为试材,研究了导管长主工分布规律,实验结果与理论结果完全一致,表明理论推导和实验结果是可靠的。     

用树脂铸型法研究4种植物木质部导管结构

导管的大小、形态和彼此连接方式的不同对水分运输和应力支撑有重要作用。本研究采用树脂铸型法对毛白杨(Populus tomentosa Carr)、旱柳(Salix matsudana)、榆树(Ulmus pumila L.)和紫藤(Wisteria sinensis)4个树种的导管分子三维结构进行比较研究,分析导管结构特征和其水分输运的关系。导管内壁结构被印在铸型的表面上,将铸型放在扫描电子显微镜下观察。结果表明：旱柳和毛白杨的导管分子特征较接近,与榆树和紫藤存在明显差异,相对于榆树和紫藤较原始。毛白杨和旱柳的导管分子长、侧壁纹孔少,有利于水分的输运。榆树和紫藤的导管分子相对宽,穿孔板几乎平直,更加利于水分的输运。榆树和紫藤的细导管分子有螺纹加厚,可增加导管的机械强度,减少管内产生空穴化的风险,从而保证水分更有效的运输。     

银桦次生木质部导管分子观察研究

对银桦 (Grevillearobusta)次生木质部导管分子进行了观察研究。在银桦次生木质部导管分子中存在着许多不同的样式 ,分别对其进行了描述 ,并从导管分子个体发育与系统发育的角度进行了讨论。银桦导管分子中还存在着特殊的样式 ,如具三个单穿孔的导管以及导管分子侧壁上存在明显的皱褶 ,对其也分别进行了讨论     

芒果次生木质部导管分子的观察

运用细胞图象分析系统及显微照相的方法对芒果(Mangifera indicaL.)次生木质部不同的导管分子进行了观察。并且对这些导管分子的构造、进化趋势以及同一导管分子上的特殊结构进行了详细的讨论。     

水同木次生木质部导管分子观察研究

运用细胞图像分析系统及显微照相方法,观察研究水同木次生木质部导管分子。结果发现,水同木次生木质部导管分子中存在着许多不同的样式,大多数导管分子短而宽,多数无尾或仅一端具尾;导管均为单穿孔板,未发现有侵填体。     

余甘子次生木质部导管分子观察研究

运用细胞图象分析系统及显微照相的方法,对余甘子次生木质部导管分子进行观察研究.结果发现,余甘子次生木质部导管分子中存在着许多不同的样式,导管分子大多数具尾;其穿孔板存在着两种类型:(1)两端均为1个单穿孔板;(2)一端为1个单穿孔板另一端为2个单穿孔板;(3)极少数的导管分子具有特殊的内含物;(4)管间纹孔式为互列纹孔式;(5)导管射线间纹孔式为混合型纹孔与横列刻痕状纹孔以及梯状穿孔.     

刺槐木质部栓塞脆弱性检测的方法比较

在全球变暖的背景下, 植物木质部栓塞脆弱性是林木死亡率升高的重要生理学因素。然而不同方法在长导管树种上建立的栓塞脆弱性曲线存在较大差异。该研究以长导管树种刺槐(Robinia pseudoacacia)为研究对象, 利用自然干燥法、Cochard Cavitron离心机法以及Sperry离心机法建立了栓塞脆弱性曲线, 旨在探讨不同检测方法的合理性。在Sperry离心法中, 使用了两种规格的转子, 从而对“开口导管假象”学说进行了检验。研究结果表明: 自然干燥法建立的栓塞脆弱性曲线为“s”形, 而Cochard Cavitron离心机法和Sperry离心机法建立的栓塞脆弱性曲线为“r”形; 自然干燥法与离心机法建立的曲线存在显著性差异, 且两种离心机法建立的曲线也具有显著性差异。尽管刺槐枝条的导管长度分布表明14.4 cm长的刺槐枝条具有更高比例的开放导管, 但用Sperry离心机法在27.4 cm和14.4 cm长茎段上建立的栓塞脆弱性曲线相似, 表明Sperry离心机法检测刺槐脆弱性曲线时未产生“开口导管假象”, 具有更为可靠的检测结果。     

植物木质部导管栓塞

植物木质部栓塞直接影响植物体内的水分传输,文章对近年来植物木质部导管栓塞的时空分布规律、栓塞修复的微观过程,以及根压与作物木质部导管栓塞的关系研究进展作了概述。     

荔枝次生木质部导管分子及穿孔板观察研究

运用细胞图像分析系统及显微照相的方法,对荔枝次生木质部导管分子进行了观察研究。在荔枝的次生木质部中导管分子存在着多种的样式,并且导管分子穿孔板存在着3种类型:两端均为一个单穿孔板;一端一个单穿孔板另一端两个单穿孔板;一端两个单穿孔板另一端三个单穿孔板。分别对其进行了描述,并从导管分子个体发育与系统发育的角度进行了讨论。     

洋蒲桃次生木质部中导管分子的解剖学

运用细胞图像分析系统和显微照相的方法对洋蒲桃（Syzygium samarangense）次生木质部导管分子进行了观察研究。次生木质部导管分子类型有：两端具尾导管、一端具尾导管和无尾导管。导管分子穿孔板存在着4种类型：两端均为具2个单穿孔的复穿孔板;一端为1个单穿孔板,另1端为具2个单穿孔的复穿孔板;两端均为单穿孔板：两单穿孔板位于同一端壁两侧相互对应以及一些过渡类型穿孔板。根据观察结果,分析了各类型穿孔板之间的演化关系。     

Isolation and characterization of microsatellite markers from Robinia pseudoacacia L

Microsatellite markers were isolated from Robinia pseudoacacia L. using an enrichment method. Eleven of the 23 primer pairs designed successfully amplified unambiguous and polymorphic single loci among 39 individual R. pseudoacacia L. from northeastern Japan. The observed and expected heterozygosities of the 11 microsatellite markers ranged from 0.333 to 0.821 and from 0.489 to 0.867, respectively. The polymorphisms observed at the 11 microsatellite loci are useful genetic data for forest ecological studies involving R. pseudoacacia L.     

Changes in phenology of the locust tree (Robinia pseudoacacia L.) in Hungary

 Intense research is being carried out on climate variability and change and the estimation and detection of anthropogenic effects. In addition to statistical methods, the use of plants, as biological indicators is becoming more popular as they are sensitive to environmental conditions. In this article we compare maps of the flowering dates of the locust tree (Robinia pseudoacacia L.) for three different time intervals between 1851 and 1994. The maps revealed noticeable shifts of dates, of approximately 3–8 days, towards earlier flowering. This change is related to the average temperature of spring (15 March–15 May), via a simple statistical model that is accurate enough to be able to quantify phenological changes and to calculate the corresponding warming. The model developed can estimate spring mean temperature using phenological data from R. pseudoacacia L. with an accuracy of 0.2° C. Estimates of mean temperature based on phenological changes are compared to climatic series. This comparison emphasizes the possibility of using R. pseudoacacia. L. as a bio-indicator. Estimates of temperature changes are also given. Received: 5 August 1996 / Revised: 14 April 1997 / Accepted: 11 November 1997     

刺槐幼苗根茎过渡区初生维管组织的观察

对不同苗龄(1-12d)的刺槐(Robinia pseudoacacia L.)幼苗进行观察,比较了其初生维管组织的发育变化。结果表明:根中的初生维管组织借助下胚轴过渡到子叶中,而茎中的初生维管组织与下胚轴中的维管组织仅是简单的连接。这与Esau等认为幼苗的外部形态可以分为根-下胚轴-子叶和上胚轴苗两个系统的观点是一致的。本研究亦证实了可以将刺槐幼苗的外部形态描述为这两个系统,二者的维管组织只是简单的连接,不存在过渡。     

Distribution of Phenylalanine Ammonia Lyase and Chalcone Synthase within Trunks of Robinia pseudoacacia L.

During heartwood formation, a kind of apoptosis in the inner parts of woody axes, phenolic substances are accumulated by in situ biosynthesis. In Robinia pseudoacacia L, these compounds are mainly flavonoids. In the present work, we performed a study to show if there is a correlation between measurable activities and detectable protein levels of phenylalanine ammonia lyase (PAL; EC 4.3.1.5) and chalcone synthase (CHS; EC 2.3.1.74), key enzymes of general phenylpropanoid metabolism and flavonoid biosynthesis, respectively. After separation of total protein extracts by one-dimensional micro-gel electrophoresis, newly emerging polypeptides were detectable within the sapwood-heartwood transition zone, pointing toward a transient activation of metabolism shortly before cell death occurs. Most prominent was a polypeptide around 46 kDa. By immunoblotting, this band was identified as a CHS subunit. Thus, the exclusive presence of both enzyme protein and extractable enzyme activity of CHS in the heartwood bordering tissue was shown. In contrast, levels of PAL protein were similar in all xylem tissues which contain living cells. PAL activity, however, was measurable only in the differentiating xylem and the sapwood-heartwood transition zone. From these results we conclude that during heartwood formation, CHS and PAL differ in their mode of regulation. It seems likely that CHS activity is regulated at the level of enzyme protein while PAL regulation is most probably post-translational.     

水分浸泡过夜对刺槐枝条最大水分导度测定的影响及年龄差异

枝条最大水分导度是植物水分生理学研究中的核心指标之一，冲洗法是当前用来测定该指标最常用的方法，但在实验测定之前首先必须要找到获得稳定的最大水分导度的可靠方法。本研究中，我们以刺槐（Robinia pseudoacacia L.）不同年龄枝条为实验材料，通过枝条采集后立即用于实验测定和枝条经超纯水中浸泡过夜后再用于实验这两种不同处理方式对不同年龄枝条最大水分导度测定的影响，检测两种处理方式中枝条最大水分导度随冲洗时间的延长是否保持恒定来判断最大水分导度测定值的可靠性，探讨提高枝条最大水分导度测定结果稳定性的有效方法。结果显示：①未浸泡过夜的当年生枝条，经150 kPa压力冲洗达到最大导水率后，继续延长冲洗时间枝条导水率会呈近线性下降，而经超纯水浸泡过夜的当年生枝条以同样实验方法达到最大导水率后，继续延长冲洗时间枝条的导水率基本保持稳定。②二年生枝条无论是否经超纯水浸泡过夜处理，经150 kPa压力冲洗达到最大导水率后枝条的导水率都基本保持稳定，但经超纯水浸泡过夜后，二年生枝条达到最大导水率所需的冲洗时间明显比未浸泡处理短。③根据茎横截面上木质部面积所占百分比和枝条木质密度判断，实验期间当年生枝条的木质化程度明显比二年生枝条低。我们推测未经浸泡过夜的当年生枝条出现木质部水分导度随冲洗时间延长而下降是由于枝条遭受机械性损伤后产生的分泌物在冲洗过程中被引入导管堵塞导管腔所致，而超纯水浸泡枝条过夜可有效降低分泌物被引入导管的可能性。因此，我们认为超纯水浸泡枝条过夜，可提高枝条最大水分导度测定结果的稳定性。     

四倍体刺槐无性系K2和K3的组织培养

1997年,北京林业大学从韩国引进了具有速生和饲料用途的刺槐(Robinia pseudoacacia L.)四倍体优良无性系,目前已在全国各省区试推广.与普通刺槐相比,四倍体刺槐具有叶大、速生等优点,且较普通刺槐有更强的适应性,耐干旱、贫瘠、烟尘及盐碱能力强,成林快,是水土保持、防风固沙及退耕还林的良好树种,可作为西北地区造林的先锋树种.     

不同土壤水分下刺槐和油松的生理特征

在适宜土壤水分(70%θf)、中度干旱(55%θf)和严重干旱(40%θf)3种土壤水分条件下研究了黄土高原常见造林树种刺槐(Robinia pseudoacacia L.)和油松(Pinus tabulaeformis Carr.)的生长及水分利用特性.结果表明:干旱胁迫使2树种的成活率、干物质累积和光合速率均显著下降.在适宜水分下刺槐的单叶水分利用率(WUE)最高,严重干旱下最低.刺槐和油松的枝条快速生长期主要集中在3-6月,在中度干旱条件,2个树种均可良好生长;在严重干旱下2个树种的生长均受到显著抑制,但刺槐受影响较大,油松受影响较小.在3种土壤水分条件下刺槐耗水量、生物量及水分利用率均显著高于油松.2树种在中度干旱下的总WUE最高,严重干旱下最低.刺槐属于高耗水树种,油松属于低耗水树种,油松的耐旱性强于刺槐.研究结果表明,刺槐在黄土高原缺水地区不适宜大面积栽植,只能用于水分条件较好的立地条件下造林.油松应尽可能在含水量较高的阴坡或沟坡地带造林.     

Hydrogen uptake by Robinia pseudoacacia nodules

Summary Hydrogen uptake is thought to increase the efficiency of nitrogen fixation by recycling H₂ produced by nitrogenase that would otherwise be lost by diffusion. Here we demonstrate the capacity of eight Rhizobium strains to take up molecular hydrogen. Uptake by nodule homogenates from Robinia pseudoacacia was measured amperometrically under nitrogenase repression. Markedly lower activities were found than in soybean nodules. In addition hydrogenase activity was detected by the ability of bacteroids to reduce methylene blue in the presence of hydrogen. It was demonstrated that hydrogenase structural genes are present in the black locust symbiont, Rhizobium sp. strain R1, using hybridization with a plasmid, which contained hydrogenase genes from R. leguminosarum bv. viceae.     

保水剂对干旱胁迫下刺槐叶绿素a荧光动力学参数的影响

研究了保水剂对干旱胁迫下刺槐叶绿素a荧光动力学参数的影响。结果表明,在干旱胁迫下刺槐叶绿素a荧光动力学参数Fv/Fm,δPSⅡ,qp,NPQ均有所下降,且随着保水剂用量增大,下降程度减小,即保水剂用量越大,对受刺槐干旱胁迫的缓解作用愈明显。保水剂不同水平处理对刺槐叶绿素荧光参数的影响达到显著水平。多重比较结果表明,土壤中保水剂用量只有在不低于0.5kg/m^3时才能有效地发挥抗旱作用。     

Formation of heartwood substances in the stem of Robinia pseudoacacia L.

Summary The activities of two key enzymes in flavonoid biosynthesis, phenylalanine ammonia-lyase (PAL, E.C. 4.3.1.5) and chalcone synthase (CHS, E.C. 2.3.1.74) were determined in the trunkwood of Robinia pseudoacacia L. The trees under investigation were cut at different times of the year (September, November, January and April). At all times PAL is active, both in the youngest wood layer (the outermost growth ring) and at the sapwood heartwood boundary. On the other hand, CHS is active exclusively in the vicinity of the heartwood boundary. The results indicate that PAL is involved both in the formation of lignin (outermost annual ring), and in flavonoid biosynthesis (heartwood boundary). Highest activity of both PAL and CHS could be measured at the sapwood heartwood boundary in the tree felled in November, indicating that heartwood formation was occurring mainly at that time. The flavonoids accumulated in the heartwood are obviously formed in situ and seem to be transported only to a minor extent — if at all — via the phloem and the ray cells to the heartwood.