河南鸡公山自然保护区野生保护植物优先保护定量分析

运用濒危系数、遗传价值系数和物种价值系数,对鸡公山自然保护区重点保护的37种野生植物的优先保护顺序进行定量分析。结果表明：最优先保护的有野八角、细茎石斛、天目木姜子和扇叶杓兰4种,占总数的10．81％;优先保护的有独花兰、天麻、天竺桂、楠木、莲、黑节草、三尖杉、中国粗榧、豹皮樟、青钱柳、河南山胡椒和河南鹅耳枥12种,占总数的32．43％;次优先保护的有香果树、榉树、黄檗、青檀、野菱、大果榉、黑壳楠、刺揪、铜钱树、珂楠树、暖木、玉铃花和万年青13种,占总数的35．14％;一般保护的有金荞麦、中华结缕草、野大豆、枫香、重齿槭、绞股蓝、飞蛾械和独根草8种,占总数的21．62％。提出进一步加强国家重点保护野生植物的保护对策。     

不同基质对三种樟科植物种子萌发及幼苗生长的影响

以河沙、草木灰、锯末配成的三种栽培基质为试验材料,以黑壳楠、楠木、闽楠为供试品种,采用露天播种育苗的方式,研究不同基质对三种樟科植物种子的萌发、幼苗生长情况的影响.结果表明:黑壳楠在河沙中的发芽率、发芽指数最高,幼苗生长情况最好;楠木和闽楠在河沙+草木灰的基质中萌发情况和幼苗生长情况最好.     

The ultrastructure of intercellular passageways in vessels of yellow poplar (Liriodendron tulipifera,L.) part I: Vessel pitting

Summary The newly matured intervessel pit membranes of yellow poplar contain distinct openings. With increasing age the membranes become progressively occluded with incrustations which obstruct the small openings. Openings were not detected in the vessel-to-ray parenchyma and vessel-to-fiber pit membranes at any age.Paper No. 3478 of the Journal Series of the N. C. State University Agricultural Experiment Station, Raleigh, N. C.     

樟科中5种国家保护树种的种子及幼苗研究

就闽楠、桢楠、浙江楠、舟山新木姜子、天目木姜子等5种樟科中列入国家保护的珍贵树种培育出的幼苗进行观察、记载和绘制成图,并从种子(果实)到幼苗的整个发展过程,以及种子和苗木的生产技术做了细致的探索性的研究。     

Preliminary evaluation of cytotoxic properties of Laurus nobilis leaf extracts

n-Hexane, ethanol and water extracts of Laurus nobilis L. leaves were evaluated for cytotoxic properties using the Brine shrimp bioassay. Only the n-hexane extract exhibited cytotoxic activity.     

Boron influences pollen germination and pollen tube growth in Picea meyeri

To study the role of boron in pollen germination and pollen tube growth of Picea meyeri Rehd. et Wils., pollen grains were cultured in standard medium or boron-deficient medium. Effects of boron on the localization of pectins and callose in the walls of pollen tubes were observed by laser scanning confocal microscopy after staining with aniline blue or immunolabeling with antibodies JIM5 and JIM7. Changes in the structures of pectins and phenolics were investigated by fourier transform infrared (FTIR) microspectroscopy. Pollen germination in boron-deficient medium ranged from 18 to 24%, whereas pollen germination in standard medium reached 61%. Callose accumulated in the tip-regions of pollen tubes cultured in boron-deficient medium, but not in standard medium. Immunolabeling with antibody JIM5 revealed that acidic pectin preferentially accumulated in the tip regions of pollen tubes cultured in boron-deficient medium, whereas acidic pectin was weakly distributed along the entire lengths of pollen tubes cultured in standard medium. Esterified pectin, detected by immunolabeling with antibody JIM7, showed a similar distribution pattern in pollen tubes in both the boron-deficient and standard treatments. The FTIR spectra indicated slight increases in contents of phenolics and carboxylic acids and a substantial decrease in the content of saturated esters in boron-deficient pollen tubes compared with normal pollen tubes. The FTIR spectra confirmed that boron deficiency enhanced acidic pectin accumulation in pollen tubes, which may be associated with the increased content of carboxylic acid. We conclude that boron has a regulatory role in pollen germination and pollen tube growth.     

Dynamics of violaxanthin and lutein epoxide xanthophyll cycles in Lauraceae tree species under field conditions

Two xanthophyll cycles have been described in higher plants: the violaxanthin xanthophyll (V or VAZ) cycle, which is present in all species, and the taxonomically restricted lutein epoxide xanthophyll (Lx) cycle, which involves the light-induced de-epoxidation of Lx to lutein (L) and its epoxidation back to Lx in low light. Laboratory experiments indicate that the first reaction occurs quickly, but the second reaction is much slower. We investigated the Lx cycle under field conditions in several tree species of the Lauraceae family to determine its relationship with the ubiquitous V cycle. The field study was conducted in two natural laurel forests: one in the Canary Islands, where Laurus azorica (Seub.) Franco, Ocotea foetens (Aiton.) Benth, Apollonias barbujana (Cav.) Bornm. and Persea indica (L.) Spreng were studied; and one in the Basque Atlantic coast where Laurus nobilis L. was studied. The results were complemented by a taxonomic study. The presence of Lx was widespread among Lauraceae species, but its concentration varied even among closely related species. The V pool size correlated positively with growth irradiance, whereas the relationship between Lx pool size and growth irradiance varied with species. A functional Lx cycle was confirmed under field conditions only in O. foetens and L. nobilis. Furthermore, in O. foetens, a correlation between Lx de-epoxidation and photoinhibition suggested a protective role for this cycle. We conclude that, unlike the V cycle, which is normally correlated with irradiance, the operation and light dependence of the Lx cycle is species-dependent.     

Homoplastic occurrence of perforated pit membranes and torus-bearing pit membranes in ancestral angiosperms as observed by field-emission scanning electron microscopy

Recent studies demonstrated that perforated pit membranes (i.e., pit membranes with a large opening in their central portion) are commonly present between wood fibers in core eudicots. It is unclear whether this type of pit membranes might also occur in ancestral angiosperms. Therefore, structure of interfiber pit membranes was examined by field-emission scanning electron microscopy in nine species representing seven families that are located at more ancestral position than core eudicots. We found perforated pit membranes in three of the nine species. Our observations indicate that perforated pit membranes are relatively common even in ancestral groups of angiosperms. In the non-perforated pit membranes of the other six species, we found a range of structural variations. Thin-walled pit membranes without apparent intercellular layers were always found in three of the six species and the porosity of sheet-like pit membranes differed among the three species. Unlike the thin-walled pit membranes, interfiber pit membranes of Buxus microphylla var. japonica were thick-walled with obvious intercellular layers, and in Schisandra chinensis, we often observed torus-bearing pit membranes. Such variations in layered structure of pit membranes and homoplastic occurrence of torus-bearing pit membranes have not yet been reported for ancestral angiosperms. Our observations indicate that the structure of interfiber pit membranes might be more complicated than previous studies might suggest.     

Repellent activity of five essential oils against Culex pipiens

Essential oils extracted from the seeds of anise (Pimpinella anisum), dried fruits of eucalyptus (Eucalyptus camaldulensis), dried foliage of mint (Mentha piperita) and basil (Ocimum basilicum) and fresh foliage of laurel (Laurus nobilis) were tested for their repellency against the adult females of Culex pipiens. All essential oils showed repellency in varying degrees, eucalyptus, basil and anise being the most active.     

Preliminary assay on the antioxidative activity of Laurus nobilis extracts

Antioxidative activity of Laurus nobilis leaves, bark and fruit methanolic extracts (crude and defatted) were studied on the level of lipid peroxidation in liposomes, induced by Fe(2+)/ascorbate system and measured spectrophotometrically by the TBA-test. The most significant inhibition of lipid peroxidation was obtained with methanolic extracts of laurel bark (70.6% of inhibition was obtained with 1.0 mg of crude extract).     

Gas exchange characteristics of a Canarian laurel forest tree species (Laurus azorica) in relation to environmental conditions and leaf canopy position

Diurnal courses of gas exchange were measured over a 1-year period in fully expanded current-year leaves in the upper (sun-exposed, 18 m above ground) and the lower (shaded, 12 m above ground) canopy of Laurus azorica (Seub.) Franco, a major canopy species of the Canarian laurel forest in Tenerife, Canary Islands, Spain. Laurus azorica exhibited high leaf plasticity in gas exchange characteristics, with a maximum carbon assimilation rate (Amax) of shade leaves about 50% that of sun leaves. This difference reflects the high leaf area index (LAI) of the stand and the correspondingly sharp light attenuation with increasing canopy depth. In sun leaves, Amax peaked at about 11 micromol m-2 s-1 and maximum transpiration (E) was about 8 mmol m-2 s-1, which corresponded with a maximum stomatal conductance (gs) of about 650 mmol m-2 s-1. Mean maximum instantaneous water-use efficiency (WUE) was 1.5 mmol mol-1 and the mean maximum A/gs was 20-35 micromol mol-1. Mean minimum internal CO2 concentration (Ci) was 225 micromol mol-1. Although high air vapor pressure deficit (VPD) caused a small decrease in gs, it remained high enough to maintain relatively high A and E. These gas exchange characteristics indicate a non-conservative use of water, which is appropriate for a species subject to droughts that are mild or of short duration. In this respect, Laurus azorica differs from its congener, L. nobilis L., of the Mediterranean region and other shrubs growing in Mediterranean-type climates in California and Chile that have to withstand more severe or more prolonged droughts.     

Novel plasmodesmata association of dehydrin-like proteins in cold- acclimated Red-osier dogwood (Cornus sericea)

Dehydrins are proteins associated with conditions affecting the water status of plant cells, such as drought, salinity, freezing and seed maturation. Although the function of dehydrins remains unknown, it is hypothesized that they stabilize membranes and macromolecules during cellular dehydration. Red-osier dogwood (Cornus sericea L.), an extremely freeze-tolerant woody plant, accumulates dehydrin-like proteins during cold acclimation and the presence of these proteins is correlated with increased freeze tolerance (Karlson 2001, Sarnighausen et al. 2002, Karlson et al. 2003). Our objective was to determine the location of dehydrins in cold-acclimated C. sericea stems in an effort to provide insight into their potential role in the freeze tolerance of this extremely cold hardy species. Abundant labeling was observed in the nucleus and cytoplasm of cold-acclimated C. sericea stem cells. In addition, labeling was observed in association with plasmodesmata of cold-acclimated vascular cambium cells. The unique association of dehydrin-like proteins with plasmodesmata has not been reported previously.     

Essential oils of commonly used plants as inhibitors of peroxynitrite-induced tyrosine nitration

The essential oils obtained from fifteen relevant and commonly used plants belonging to Cruciferae, Lamiaceae, Lauraceae, Apiaceae, and Zingiberaceae were screened using an in vitro model of peroxynitrite-induced tyrosine nitration. Almost complete inhibition of 3-nitrotyrosine formation (91% at 300 microg/ml) was achieved only with the essential oil obtained from the leaves of Laurus nobilis. 1,8-Cineol, accounting for a 50% of this essential oil, which resulted as inactive in this model, thus evidencing a major role for the minor volatile compounds present in the leaves.     

Polysaccharides in some industrially important hardwood species

The amount and composition of sugar units comprising polysaccharides in sapwood and heartwood, or stemwood, of 11 industrially important pulpwood species were analysed. The polysaccharide content was between 60 and 80% (w/w) for all species, with cellulose as the predominant polysaccharide type and glucuronoxylans as the main non-cellulosic polysaccharides. The second most abundant non-cellulosic polysaccharides were either pectins, i.e. polygalacturonic acids, or glucomannans. The amount of acidic sugar units were 15–23% of the total amount of non-cellulosic sugar units in all samples, with the Acacia species in the high end. The amount and composition of water-soluble carbohydrates from ground wood samples were also analysed, since these are important in mechanical and chemimechanical pulping, and as a possible source of bioactive polymers. Sapwood released more carbohydrates than heartwood for most species. It is to be noted that the relative amount of dissolved acidic sugar units was larger from the heartwood than from the sapwood for all species. Probably due to the mild treatment conditions, the main dissolved polysaccharides were xylans only for a few samples, while easily soluble galactans, arabinogalactans, or mannans dominated in most species. Pectins dominated in heartwood of Populus grandidentata. Generally, pectins and acidic xylans were the main acidic polysaccharides.     

Ⅰ-69杨湿心材发生、分布及材性的研究*

在湖北省嘉鱼县潘家湾,不同生长条件和不同方式种植的I-69杨活立木及原木都有不同程度的湿心材存在。湿心材的比例与土壤水分含量有关,与种植方式和树木生长速度无关。湿心材的存在和变色由细菌活动引起,已分离和鉴定出5种病原菌(Erwinia carotovora Subsp.carotovora,E.rhapontioi (Millard)Burkhold,E.chrysanthemi Burkholder,Bacilluscereus Frankland,B.sphaericus Neide)。电镜观察和材性分析表明,正常材中细菌很少,纹孔膜保存完好,而湿心材的导管-射线间纹孔和管间纹孔膜几乎都被破坏。与正常材相比,湿心材的pH和酸缓冲容量高,抽提物和灰分含量较高,综纤维素和α-纤维素含量略低。湿心材的密度、干缩系数及力学性质都比正常材低,差异极显著。建议进一步研究如何防止细菌的侵入和活动,阻止湿心材和变色材的发生。     

Contribution to the knowledge of the folk plant medicine in Calabria region (Southern Italy)

A series of research on plants used in Calabria (Southern Italy) in the folk plant medicine was carried out in the last twenty years. The use of 104 taxa distributed into 42 families are described. Among the major findings: Ceterach officinarum as hypotensive; Heliotropium europaeum in the case of urinary inflammations; Silybum marianum for haemorrhoids; Arundo donax for pertussis and cystitis; Allium cepa for sties and flu; Laurus nobilis as galactagogue; Passiflora incarnata for burns, haemorrhoids and skin inflammations; Scrophularia canina for rhagas and wounds; Urtica membranacea for tussis and tonsillitis.     

Permeability of <Emphasis Type="Italic">Tectona grandis</Emphasis> L. as affected by wood structure

This experiment describes some anatomical features of Tectona grandis L. relating to the variation of liquid permeability in radial and longitudinal directions. Safranine aqueous solution was used to measure the permeability for its brilliant color and staining properties. Even in presence of abundant rays, penetration depth of liquid in radial direction was found very low in comparison with axial flow. Herein ray length and perimeter of cross-sectional area, interparenchymatous pit number and diameter determined the radial permeability. On the other hand, vessel length and diameter, intervessel pit size, and fiber length affected the longitudinal flow of liquids. Following a go-stop-go cycle, penetration speed of liquid decreased over time.     

福建明溪闽楠天然林主要种群生态位研究

对福建省明溪县翰仙镇大岬洲闽楠群落中12个主要种群的生态位特征进行研究,结果表明:闽楠、黑壳楠、沉水樟、枫香、红楠是广生态位树种,尖叶水丝梨、薯豆、拟赤杨是狭生态位树种。闽楠与生态位较宽的树种相似程度大,并易与这些阔叶树种形成混交林。群落内各种间的竞争不十分剧烈,群落尚处于不稳定状态。     

Variability of the chemical composition of pit membranes in bordered pits of gymnosperms

Summary The pit membranes of the bordered pits in about one hundred coniferous wood species were investigated in regard to their chemical composition, in particular to the aromatic compounds. In many species pit membranes, even in the sapwood, contain phenolic substances. In heartwood, normally lignification takes place besides the development of other polyphenols. The variability of these compounds, both in sapwood an in heartwood, may be considerable not only between species but also within the same species and even between neighbouring tracheids and pits respectively.We are thankful to Prof. Dr. W. Liese for his support and his frequent discussions.     

香叶树和杉木人工林生产力的比较研究

通过对28年生香叶树与杉木人工林生长和生物量测定,进行香叶树和杉木人工林生产力的比较研究,结果表明：香叶树是一种生长迅速的阔叶树种,其人工林蓄积量为421.88m^3/hm^2,比杉木人工林高7.09%;香叶树人工林分生物量为305.43t/hm^2,是杉木人工林的1.59倍,其生物量乔木层是杉木林的1.68倍.