7种桉树花粉微观形态及其亲缘关系分析

为了解我国常用桉树树种的亲缘关系,利用扫描电镜观察7种桉属(Eucalyptus)树种的花粉形态。结果表明,粗皮桉(E.pellita)、窿缘桉(E. exserta)的7个花粉性状大多处于前2位,其中粗皮桉花粉的赤道面长、宽和面积最大,分别为17.522、17.090μm和300.830μm~2,而窿缘桉花粉的萌发沟长、宽和大小最大,分别为6.576、0.720μm和4.718μm~2;赤桉(E. camaldulensis)花粉的赤道面最小,韦塔桉(E.wetarensis)花粉的萌发沟最小。聚类分析表明,在信息保留87.5%时,7树种可以分为3组,粗皮桉和窿缘桉聚在一组,韦塔桉和巨桉(E. grandis)聚在一组,其余聚在一组。粗皮桉、窿缘桉的花粉外壁纹饰较光滑,细叶桉(E. tereticornis)和赤桉属常规,尾叶桉(E. urophylla)、韦塔桉和巨桉较粗糙。从花粉形态分析,粗皮桉和窿缘桉的亲缘关系较近,韦塔桉、尾叶桉的亲缘关系较远,细叶桉、赤桉和巨桉的亲缘关系与传统分类结果一致。因此,7种桉树花粉形态反映了一些新的亲缘关系,对桉树的杂交育种有指导意义。     

广东樟木头5种桉树的能量特征研究

对广东省东莞市樟木头林场5种6 a生巨桉(Eucalyptus grandis)、柳桉(E.saligna)、大花序桉(E.cloeziana)、粗皮桉(E.pellita)和托里桉(E.torelliana)的能量特征进行研究.结果表明:5种桉树不同组分的灰分含量和热值存在显著差异(P<0.01).灰分含量为0.16%-8.37%,其中巨桉、柳桉、粗皮桉和托里桉均是叶>皮>枝>根>干,而大花序桉为皮>叶>枝>根>干;各组分的干重热值为15.12-18.85 kJ g~(-1),均以叶最高、皮最低,巨桉与粗皮桉为叶>枝>干>根>皮;柳桉与托里桉为叶>干>枝>根>皮;大花序桉为叶>枝>根>干>皮;去灰分热值为16.37～19.87 kJ g~(-1),除粗皮桉为叶>枝>皮>干>根外,其它4种各组分的去灰分热值均与干重热值的变化趋势相同.5种桉树的平均干重热值和去灰分热值分别以巨桉、粗皮桉最高,但均以托里桉最低.     

桉树及其杂交种叶片形态的遗传变异特征

为了解桉树重要性状在杂交种亲本、子代间的遗传变异规律,以尾叶桉(Eucalyptus urophylla)为母本、粗皮桉(E. pellita)和细叶桉(E. tereticornis)为父本、8个全同胞杂交子代为材料,对亲本和子代的叶片形态性状进行了分析。结果表明,亲缘关系近的尾叶桉和粗皮桉的叶片性状大多无显著差异;但他们与亲缘关系远的细叶桉间的差异显著;尾粗桉与父母本间的性状无显著差异或仅与母本差异显著,属偏父本型;尾细桉与双亲间的多数性状都差异显著,且多偏向于母本。在树种内的家系间或个体间,叶片数量性状差异显著,而质量性状仅叶面革质厚度、叶面朝向差异显著;杂交种家系部分性状有超亲现象,且尾细桉家系超亲频率显著高于尾粗桉。叶长、叶长宽比、形状因子、叶色、叶面革质是区别叶片形态特征的决定性状。     

闽西山地耐寒桉属树种/种源引种试验研究

对5.5年生21种耐寒桉树的53个种源在闽西山地的保存率和生长性状进行了比较分析。结果表明:树高、胸径、单株材积和保存率在树种/种源间均存在显著或极显著差异。经聚类分析可将参试树种/种源分为5类,适宜在闽西山地推广种植的树种包括巨桉(Eucalyptus grandis)、邓恩桉(E.dunnii)、柳桉(E.saligna)、边沁桉(E.benthamii var.benthamii)、道里格白桉(E.dorrigornsis)和赤桉(E.camaldulensis)等,其中巨桉的最优种源是来自Near Coffs Harbour NSW的20116号,5年生时材积生长量达171.03 m3hm-2,邓恩桉的最优种源是来自NSW的20633号,5年生时材积生长量达158.61 m3hm-2,边沁桉的最优种源是来自NSW的18788号,5年生时材积生长量达110.96 m3hm-2。原产地海拔对桉树的适应性影响不大,而降雨的分布类型是引种成功与否的关键性因子,最优树种/种源是来自南纬26°～30°澳大利亚昆士兰州南部、新南威尔士和维多利亚北部内陆夏雨型树种/种源,邓恩桉、巨桉、边沁桉和柳桉可耐-4～-4.5℃的低温,适宜在闽西山地引种栽培。     

花楸树种源间表型性状的地理变异分析

为揭示花楸树[ Sorbus pohuashanensis (Hance) Hedl.]表型性状的地理变异规律,对来源于山东、山西和河北的7个花楸树种源171个家系2年生幼苗的株高、地径、复叶长、复叶宽、叶柄长、小叶长、小叶宽、复叶长宽比和小叶长宽比9个表型性状进行了比较,并进行了方差分析、主成分分析(PCA)及聚类分析;在此基础上,分析了各种源株高和地径与主要地理-气候因子的相关性.结果表明:在种源间及种源内家系间 9个表型性状均有极显著差异;7个种源幼苗的平均株高和平均地径变幅分别为54.21～ 63.07 cm和8.12 ～8.45 mm;叶片各项指标的变幅相对较小,变幅最大的为叶柄长,为1.87 ～3.05 cm;9个性状在种源间的表型分化系数为12.98％～54.04％,其中小叶长的表型分化系数最大(54.04％),株高的表型分化系数最小(12.98％),种源间各性状的平均表型分化系数为34.38％.主成分分析结果表明:花楸树表型性状之间的差异主要表现在小叶长和宽,其次是复叶长和宽.通过聚类分析可将7个种源划分为2组,其中,山东崂山和泰山种源聚为I组;山西庞泉沟及河北白石山、驼梁山、雾灵山和塞罕坝5个种源聚为Ⅱ组.相关性分析结果表明:花楸树株高与纬度呈显著负相关、与降雨量呈显著正相关(P=0.05);地径则与经度、年均温和年降雨量呈显著正相关(P=0.05).研究结果显示:花楸树的各项表型性状在种源间以及种源内家系间存在丰富的变异、遗传分化显著,其中种源内家系间的变异是花楸树表型变异的主要来源.初步判断花楸树表型性状的变异为经纬向双重变异模式,其中纬度起主要作用.     

水杉年轮宽度和管胞形态径向变异研究

采用木材切片法和光学显微技术,研究了四川省雅安市中里地区水杉木材年轮宽度和管胞的长度、壁厚、腔径等指标的径向变异。结果表明:(1)年轮宽度在髓心至第10年先迅速增加,然后呈下降趋势,速生期约15 a,晚材率低;(2)管胞长度随轮龄的增加而增大,13 a后增幅变缓,早材管胞长度小于晚材管胞,根据管胞长度判断实验水杉木材即将进入成熟期;(3)管胞宽度在轮龄10 a前增长迅速,幅度明显减慢,管胞宽度44.6μm,壁厚7.23μm,腔径37.48μm,早、晚材间管胞宽度、壁厚、腔径差异显著;(4)管胞长宽比95.4、壁腔比0.27、腔径比0.82,水杉木材是优良的造纸原料。     

RAPD标记在韦塔桉种源遗传结构上的应用

采用适合韦塔桉RAPD分析的PCR扩增体系,对13个不同种源的韦塔桉运用20个不同随机引物进行了DNA序列多态性分析。实验结果表明韦塔桉不同种源间遗传多态性水平较高,共扩增出165个位点,其中多态位点占77.0%;13个种源间遗传分化指数值为0.5717-0.6670,遗传分化百分比值为0.090%-5.989%。根据遗传分化百分比值构建了13个种源之间的聚类图,聚类图显示了韦塔桉种源间的亲缘关系,17830、17831、17832、17833、17834、17835、17836、17837这7个种源相对聚在一起,17838种源与其它种源的相似性水平最低。对韦塔桉不同种源的RAPD研究为其种源的早期选择了科学依据。     

寿竹的秆形特征及纤维形态研究

为探讨寿竹(Phyllostachys reticulata ‘Shouzhu’ Yi)的材质特性,分析寿竹的造纸性能, 以毛竹(Phyllostachys edulis)和慈竹(Bambusa emeiensis L. C. Chia & H. L. Fung)为对照,对重庆市梁平县寿竹秆形结构的垂直变化、材积与生物量以及纤维形态特征进行研究。结果表明,寿竹秆的节间长度随竹高度呈现先长后短的变化趋势,直径与壁厚均随竹秆高度的增加而逐渐减小。寿竹材积的模型为V=0.000939H+0.001861D-0.01374,生物量模型为W=1.297D+2.053H-16.666。寿竹纤维长度平均为2.47 mm,以2~3 mm分布最多,长宽比大于100,属于制作优良纸张的较好纤维;纤维壁腔比较大,达3.85。相对毛竹而言,寿竹竹秆的节间长度更长,垂直方向上材积分布更加均匀,纤维长、长宽比大。寿竹与慈竹的纤维长度差异不大,但纤维长宽比小于慈竹,壁腔比大于慈竹。寿竹节间长,垂直分布均匀,材积和生物量大,是优良的板材利用原料;寿竹纤维长,长宽比大,是优良的造纸原料,造纸性能优于毛竹略次于慈竹。     

灰木莲种源幼苗叶片性状表型多样性分析

以越南收集的12个灰木莲（Manglietia conifera Dandy）种源为材料,对叶片形态性状（叶长、叶宽、叶面积、叶周长、长宽比、叶柄）以及微形态特征（气孔器密度、气孔器长、气孔器宽、气孔器面积、长宽比）进行测定,采用方差分析、变异系数、相关分析和主成分分析等方法进行分析。结果表明：灰木莲不同种源间的叶表型性状存在显著差异;种源中,LC2的叶形态性状的平均变异系数最大（22.09%）,TQ2的变异系数最小（12.76%）;叶表型性状中,叶面积的变异系数最大（28.60%）,气孔器宽的变异系数最小（5.19%）;相关性分析结果表明叶表型性状间存在显著或极显著的相关关系,而地理因素中经度与叶周长显著相关,经纬度与叶长宽比呈显著相关,海拔与叶表型性状间的相关性不显著（P<0.05）;主成分分析表明前3个主成分的累计贡献率达到了89.29%,基本代表原始性状的全部信息。灰木莲12个种源经聚类分析在欧式距离5阈值处可分为4类。灰木莲种源间的叶表型性状存在着丰富的变异,纬度对灰木莲叶形态特征有明显影响,灰木莲种源间和性状间的变异程度存在着差异,本研究为灰木莲遗传改良提供理论依据。     

葛藤纤维的形态和化学组成及其与产地和生长时间的相关性

对来源于浙江省不同产地及生长时间不同的葛[Pueraria lobata (Willd. ) Ohwi]藤纤维的形态指标和化学组成进行了测定,并对地理因素和生长时间与葛藤纤维的形态指标和化学组成的相关性进行了分析.测定结果显示,不同产地葛藤纤维的平均长度和平均宽度分别为3.25 mm和13.66 μm,平均长宽比为237.98,不同产地间葛藤纤维长度和长宽比差异不显著(P>0.05);不同产地葛藤纤维的水分、灰分、冷水抽出物、热水抽出物、1%氢氧化钠抽出物、有机溶剂抽出物、酸不溶木素、综纤维素及多戊糖含量分别为12.09%～13.53%、 4.72%～5.40%、 5.74%～6.13%、7.74%～10.74%、30.96%～33.26%、4.23%～4.56%、18.76%～21.40%、65.16%～69.20%和22.69%～24.01%,其中仅冷水抽出物含量在不同产地间差异不显著.随生长时间的延长,葛藤纤维的长度、宽度及长宽比逐渐增加,差异达显著水平(P<0.05);水分和灰分含量逐渐降低,各种抽出物和酸不溶木素及综纤维素含量随生长时间的延长逐渐提高,差异达显著水平(P<0.05).相关分析结果表明,葛藤纤维的形态指标与经度和纬度的相关性较小,但海拔与纤维长度和长宽比分别有极显著(P<0.01)和显著(P<0.05)的正相关关系;除1%氢氧化钠抽出物与纬度存在显著的负相关关系(P<0.05)外,葛藤纤维各化学组成与经度、纬度及海拔的相关性均不显著.葛藤纤维的长度、宽度和长宽比与葛藤的生长时间均呈极显著的正相关性(P<0.01);葛藤的生长时间与水分和灰分含量分别呈显著(P<0.05)和极显著(P<0.01)的负相关性,与多戊糖含量呈不显著的负相关性(P>0.05);各种抽出物含量及酸不溶木素和综纤维素含量与葛藤的生长时间分别具有显著或极显著的相关性.研究结果表明,生长时间适宜的葛藤纤维可开发成为优质造纸原料.     

Foreign exploration for Scirtothrips perseae Nakahara (Thysanoptera: Thripidae) and associated natural enemies on avocado (Persea americana Miller)

Scirtothrips perseae Nakahara was discovered attacking avocados in California, USA, in 1996. Host plant surveys in California indicated that S. perseae has a highly restricted host range with larvae being found only on avocados, while adults were collected from 11 different plant species. As part of a management program for this pest, a “classical” biological control program was initiated and foreign exploration was conducted to delineate the home range of S. perseae, to survey for associated natural enemies and inventory other species of phytophagous thrips on avocados grown in Mexico, Guatemala, Costa Rica, the Dominican Republic, Trinidad, and Brazil. Foreign exploration efforts indicate that S. perseae occurs on avocados grown at high altitudes (>1500 m) from Uruapan in Mexico south to areas around Guatemala City in Guatemala. In Costa Rica, S. perseae is replaced by an undescribed congener as the dominant phytophagous thrips on avocados grown at high altitudes (>1300 m). No species of Scirtothrips were found on avocados in the Dominican Republic, Trinidad, or Brazil. In total, 2136 phytophagous thrips were collected and identified, representing over 47 identified species from at least 19 genera. The significance of these species records is discussed. Of collected material 4% were potential thrips biological control agents. Natural enemies were dominated by six genera of predatory thrips (Aeolothrips, Aleurodothrips, Franklinothrips, Leptothrips, Scolothrips, and Karnyothrips). One genus each of parasitoid (Ceranisus) and predatory mite (Balaustium) were found. Based on the results of our sampling techniques, prospects for the importation of thrips natural enemies for use in a “classical” biological control program in California against S. perseae are not promising.     

Phylogeny of cardinalfishes (Teleostei: Gobiiformes: Apogonidae) and the evolution of visceral bioluminescence

The cardinalfishes (Apogonidae) are a diverse clade of small, mostly reef-dwelling fishes, for which a variety of morphological data have not yielded a consistent phylogeny. We use DNA sequence to hypothesize phylogenetic relationships within Apogonidae and among apogonids and other acanthomorph families, to examine patterns of evolution including the distribution of a visceral bioluminescence system. In conformance with previous studies, Apogonidae is placed in a clade with Pempheridae, Kurtidae, Leiognathidae, and Gobioidei. The apogonid genus Pseudamia is recovered outside the remainder of the family, not as sister to the superficially similar genus Gymnapogon. Species sampled from the Caribbean and Western Atlantic (Phaeoptyx, Astrapogon, and some Apogon species) form a clade, as do the larger-bodied Glossamia and Cheilodipterus. Incidence of visceral bioluminescence is found scattered throughout the phylogeny, independently for each group in which it is present. Examination of the fine structure of the visceral bioluminescence system through histology shows that light organs exhibit a range of morphologies, with some composed of complex masses of tubules (Siphamia, Pempheris, Parapriacanthus) and others lacking tubules but containing chambers formed by folds of the visceral epithelium (Acropoma, Archamia, Jaydia, and Rhabdamia). Light organs in Siphamia, Acropoma, Pempheris and Parapriacanthus are distinct from but connected to the gut; those in Archamia, Jaydia, and Rhabdamia are simply portions of the intestinal tract, and are little differentiated from the surrounding tissues. The presence or absence of symbiotic luminescent bacteria does not correlate with light organ structure; the tubular light organs of Siphamia and chambered tubes of Acropoma house bacteria, those in Pempheridae and the other Apogonidae do not.     

Biological control of three floating water weeds,<Emphasis Type="Italic">Eichhornia crassipes,Pistia stratiotes</Emphasis>, and <Emphasis Type="Italic">Salviniamolesta</Emphasis> in the Republic of Congo

Since 1999, four specific weevils (Coleoptera, Curculionidae) were released in the Republic of Congo against three exotic floating water weeds: Neochetina eichhorniae Warner and N. bruchi Hustache against water hyacinth, Neohydronomus affinis Hustache against water lettuce, and Cyrtobagous salviniae Calder and Sands against water fern. Recoveries of exotic weevils were made from all 24 release sites except one, and all four species have established and spread (up to 800 km for water hyacinth weevils). Within a few years of releases, control of water fern and water lettuce was such that fishing and navigation could be resumed, while reductions of water hyacinth populations were only beginning.     

Taxonomic status of the species of the green algal genusNeochloris

Komárek has recently reviewed the various species assigned to the green algal genusNeochloris Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia. Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class.     

A molecular phylogeny of Hebeloma species from Europe

In order to widen the scope of existing phylogenies of the ectomycorrhizal agaric genus Hebeloma a total of 53 new rDNA ITS sequences from that genus was generated, augmented by sequences retrieved from GenBank, and analysed using Bayesian, strict consensus and neighbour joining methods. The lignicolous Hebelomina neerlandica, Gymnopilus penetrans, and two species of Galerina served as outgroup taxa. Anamika indica, as well as representatives of the genera Hymenogaster and Naucoria, were included to test the monophyly of Hebeloma, which is confirmed by the results. Hebeloma, Naucoria, Hymenogaster and Anamika indica cluster in a strongly supported monophyletic hebelomatoid clade. All trees largely reflect the current infrageneric classification within Hebeloma, and divide the genus into mostly well-supported monophyletic groups surrounding H. crustuliniforme, H. velutipes, H. sacchariolens, H. sinapizans, and H. radicosum, with H. sarcophyllum being shown at an independent position; however this is not well supported. The section Indusiata divides with strong support into three groups, the position of the pleurocystidiate Hebeloma cistophilum suggests the possible existence of a third subsection within sect. Indusiata. Subsection Sacchariolentia is raised to the rank of section.     

Die GattungKarschia — Bindeglied zwischen bitunicaten Ascomyceten und lecanoralen Flechtenpilzen?

The genusKarschia, in the earlier sense, including saprophytes and parasites on lichens, has been thought to be a non-lichenized parallel genus of the lichen genusBuellia. Modern workers included it on the one hand inBuellia, on the other hand combined it with bitunicate ascomycetes. It is now proved thatKarschia is heterogeneous and contains but superficially similar members both of the genusBuellia of theLecanorales and of typical or masked bitunicateAscomycetes. Therefore, it can not be regarded as a link betweenLecanorales andDothideales. The type species ofKarschia belongs to theDothideales.

     

Demographic characteristics of an intertidal bay goby (Lepidogobius lepidus)

Synopsis In a fourteen month study (May 1976 – June 1977) I examined the following characteristics of an intertidal bay goby (Lepidogobius lepidus) in Morro Bay, California, U.S.A.: annual and seasonal patterns of abundance, age composition and growth rates, survivorship and mortality patterns, and the reproductive cycle for female gobies. Fishes were collected with the aid of quinaldine and otoliths and ovaries removed. Age and growth rates were estimated from otolith annuli using a back calculation formula and a Brody-Bertalanffy growth curve. Mortality rates were derived using the methods of Heincke (1913), Robson & Chapman (1960), mean age, and a catch curve (Ricker 1975). A gonad index was used to describe the annual reproductive cycle. Results indicated that abundance fluctuated seasonally and that these fluctuations appeared to be caused by reproductive emigrations. Bay gobies reached an age of 7+ and a standard length of 87 mm. Growth was relatively constant (6 mm yr⁻¹) until age 5, at which point it began to decline. The mean rates of survivorship, mortality, and instantaneous mortality were 0.75, 0.25, and 0.29 respectively. Mortality rates for individual age classes ranged from 0.13 to 0.51 and increased with age. This stock appears to reproduce mainly during the winter.     

Systematic significance of mature embryo of bamboos

The mature embryo of seven species belonging to five genera of Indian bamboos is described. In all these the basic pattern of embryo organisation is same: the scutellar and coleoptilar bundles are not separated by an internode, the epiblast is absent, the lower portion of the scutellum and the coleorhiza are separated by a cleft and the margins of embryonic leaves overlap. The features unique to fleshy fruited bamboos are: presence of a massive scutellum, the juxtaposition of plumule and radicle and the occurrence of a bud in the axil of the coleoptile. The fleshy fruit bearing bamboos should be classified into one group, the tribeMelocanneae. Evidence is provided to recognise additional groups in the subfamilyBambusoideae.