Tetrameres tarapungae n.sp. (Nematoda: Spirurida), a parasite of the red-billed gull,Larus novaehollandiae scopulinus

Abstract

Tetrameres (Tetrameres) tarapungae n.sp. is described from specimens from the proventriculus of juvenile red-billed gulls from Kaikoura, New Zealand. The male is characterised by having two short rows of lateral cervical cuticular spines that do not extend beyond the middle of the oesophagus, a body length of 2.2–2.6 mm, and the larger spicule longer than half the body length. The male tail bears four pairs of subventral papillae and two pairs of lateral papillae. The pathology of the infections is described briefly.     

Biometrical and ecological observations on Cistus salvifolius L.

Abstract

Biometrical observations on Cistus salvifolius L. (Cistaceae), a species with a very variable morphology, are presented: data, collected in Sicily, are relative to three environments in which populations of Cistus salvifolius live: garigue, maquis, pinewood. Measurements are compared with other ones, found in the literature, and in some cases they disagree or supply useful indications. On the basis of the different light regimes in the three environments, and of the parameters in which the difference among the three populations is most evident, some observations about the reaction to shade in Cistus salvifolius were made. On the basis of the few data collected, the intraspecific differences were given a possible explanation with the light factor: these differences are relative to morphological parameters such as leaf area, petiole length, stem length, and also to “derived” parameters such as specific leaf area and petiole length/leaf length ratio.     

A comparison of Dichodontium flavescens (Dicks.) Lindb. and D. pellucidum (Hedw.) Lindb. (Bryopsida)

Abstract

Fifty-three herbarium samples of the genus Dichodontium, originating from 15 countries in Europe and North America, were examined to critically assess new distinguishing characters between D. flavescens and D. pellucidum. The examination, including SEM, revealed some new characteristics in the gametophyte, notably leaf shape, leaf length: width ratio, and width of the nerve, permitting accurate determinations even on sterile material. D. flavescens is recognized here as a distinct species.     

Phospholipases. II. Enzymatic hydrolysis of lecithin: Effects of structure,cholesterol content,and sonication

Summary Hydrolysis of unsonicated liposomes of egg lecithin catalyzed by several phospholipases is markedly activated by addition ofn-alkanols [Jain & Cordes,J. Membrane Biol. 14:101 (1973)]. Further pursuit of these systems has established that several factors, including higher temperatures, increasing unsaturation of fatty acyl chains of the substrate, incorporation of cholesterol into the liposomes, and sonication, reduce the concentration ofn-hexanol required to elicit maximal activation for enzymatic hydrolysis. Moreover, sonication or incorporation of cholesterol into lecithin liposomes reduces from C₈ to C₇ and C₆, respectively, the chain length of that alcohol eliciting maximal activation. These results are consistent with the hypothesis that sonication and increasing cholesterol content lead to liposomes which have a diminished thickness of the hydrocarbon region compared to that for unmodified liposomes derived from the same lecithin.     

茎瘤芥根际一株产紫色杆菌素杜擀氏菌的分离鉴定及其基因组分析

【目的】对茎瘤芥根际微生物进行分离鉴定,分析微生物菌群构成,选择具有优良特性的菌株,评估其次级代谢产物合成能力,为茎瘤芥根际微生物多样性和菌种资源的挖掘利用奠定基础。【方法】采集重庆市涪陵区二渡村和邓家村的茎瘤芥根,分离培养根际微生物菌株,通过菌株形态观察和看家基因的序列分析,对菌株进行初步鉴定、归类和保存。选择具有优良性状的菌株,利用Pacbio RS II和Illumina HiSeq平台完成全基因组测序,通过antiSMASH分析评估其次级代谢产物合成潜力,克隆目的基因簇并进行异源表达和产物鉴定。【结果】分离得到256株微生物,初步鉴定120株;从中鉴定了一株产紫色杆菌素的杜擀氏菌BjR8,完成了基因组测序及分析,发现该菌基因组为一条环状染色体,全长7 205 593 bp,GC含量为64.67%,含有6 241个编码基因。生物信息学分析发现基因组含有9个次级代谢产物生物合成基因簇,其中7个基因簇与已知化合物编码基因簇同源性较低,说明该菌具有产生多种新型次级代谢产物的潜力;克隆得到紫色杆菌素生物合成基因簇,并在变铅青链霉菌TK23中完成了异源表达。【结论】从茎瘤芥根际分离得到25...     

An adaptative pattern for water conduction in the ectohydric moss Zygodon viridissimus var. rupestris Hartm.

Abstract

A detailed LM, SEM and TEM study of the dorsal and ventral surfaces of the leaf of the ectohydric moss Zygodon viridissimus var. rupestris (Z. baumgartneri) is described. The presence of papillae on both surfaces is confirmed and a groove, running the length of the nerve, is demonstrated. The presence of waxy particles on both surfaces is also demonstrated. A pattern for water conduction which could represent another interesting example of eco-physiological adaptation in bryophytes, is suggested.     

一株重寄生枝孢菌的基因组测序及重寄生机制分析

【背景】枝孢菌SYC63是一株具有重寄生作用和抗菌活性的潜在生防菌株,目前尚无研究报道该菌株的全基因组序列,因此限制了其开发与利用。对该菌株进行基因组测序与分析,将进一步了解其重寄生的分子机制,为其在生物防治上的应用奠定研究基础。【目的】解析枝孢菌SYC63基因组序列信息,初步探究该菌的重寄生作用机制。【方法】利用二代高通量测序平台对枝孢菌SYC63进行全基因组测序,运用相关软件对其测序数据进行基因组组装、基因功能注释、预测次级代谢产物合成基因簇并分析重寄生相关的碳水化合物酶类基因等。【结果】基因组组装后共得到17个contigs,总长度为31 912 211 bp,GC含量为52.80%,预测到12 327个编码基因。其中,4 029、949和6 595个基因分别能在KEGG、COG和GO数据库中被注释到,同时还预测到25个次级代谢产物合成基因簇。对重寄生机制相关的碳水化合物酶类进行分析并与重寄生菌株(拟盘多毛孢菌、木霉及盾壳霉)比较,发现该菌具有较多的糖苷水解酶和糖脂酶基因,而且细胞壁降解酶类基因经锈菌孢子壁处理后在转录组测序中显著上调表达,初步分析了该菌与重寄生木霉在分子水平上的...     

Phospholipases. I. Effect ofn-alkanols on the rate of enzymatic hydrolysis of egg phosphatidylcholine

Summary The rate of hydrolysis of unsonicated liposomes of egg lecithin by phospholipase A (from bee venom and Russell viper venom) and phospholipase C (fromBacillus cereus andClostridium welchii) is markedly dependent on the nature and concentration of a variety of added alcohols. Typical plots of rate against alcohol concentration are bell-shaped. The maximum rate and the alcohol concentration at which it is achieved are alcohol-specific. In a homologous series ofn-alkanols, the maximal rates increase and the optimal concentrations decrease as the chain length is increased from C₄ to C₈. For longer alcohols (C₉ to C₁₂), progressively higher concentrations are required to elicit maximal activation. The optimal activating concentrationsC for C₄ to C₈ n-alkanols obey the relationshipp C=a logP _octanol+constant [cf. Hansch & Dunn,J. Pharm. Sci. 61:1 (1972)], suggesting that the alcohol-activating effect is a consequence of their incorporation into the liposomes with resultant modification of liposomal structure.     

尖孢镰孢菌果胶裂解酶基因家族鉴定及侵染表达模式分析

【背景】番茄枯萎病是番茄生产中常见的土传真菌病害。【目的】为鉴定番茄枯萎病基因组果胶裂解酶基因家族,明确该基因家族在侵染过程表达模式。【方法】采用生物信息学方法鉴定了番茄枯萎病尖孢镰孢菌(Fusarium oxysporum f. sp. Lycopersici)基因组内PEL基因家族,并分析了基因结构、染色体定位及三级结构,同时利用荧光定量PCR分析了FoPEL1-16基因在接种番茄根系的表达情况。【结果】番茄尖孢镰孢菌基因组内PEL基因家族成员有16个。氨基酸序列长度在163-548个氨基酸,信号肽长度在16-21个氨基酸。染色体定位分析表明16个基因在染色体上分布不均,分别定位在7条染色体上。根据基因结构和保守基序分析结果 16个基因可分为4类。进化分析表明该基因家族成员可聚成4支。三级结构预测结果显示同一家族存在相似结构域。荧光定量PCR分析结果表明Fo PEL基因在侵染过程表达水平明显上升。【结论】番茄尖孢镰孢菌基因组内果胶裂解酶以基因家族形式存在,其基因结构存在差异暗示了其功能多样性;FoPEL基因在侵染过程表达明显增强,说明其参与病原菌的致病性。本研究为解析尖孢镰孢菌致病基因功能分析及寄主病原互作提供了重要理论基础。     

Flower colour variation in the montane plant Gentiana lutea L. (Gentianaceae) is unrelated to abiotic factors

Background: Flower colour variation among populations may result from the spatial variation of selective agents. The structure of phenotypic variation informs on the ecological processes related to this variation. Variation in floral traits is mainly attributed to variation in the pollinator fauna, while variation in vegetative traits is usually linked to abiotic factors or herbivores.

Aims: We investigated the geographical variation of flower colour (and correlated traits) in Gentiana lutea and the relationship with the variation in abiotic factors.

Methods: Phenotypic variation (flower colour, petal length, petal width, stalk length, leaf length, flower number, petal number and number of basal leaves) was assessed in 429 plants of 12 populations located at north-west Iberia. Additionally, we obtained data on the geographical coordinates, elevation, temperature, rainfall and radiation for each population.

Results: Populations mostly differed in flower colour, from orange to yellow from west to the east. Abiotic factors were unrelated to variation in either floral or vegetative traits.

Conclusions: Phenotypic variation among G. lutea populations does not result from adaptation to environmental factors. Other factors, such as historical events or selective pressure exerted by biotic interactions, might explain the flower colour variation in G. lutea along the Cantabrian Range.     

Plagiochila atlantica F. Rose,sp. nov.—P. amhagiosa auct.

Abstract

The Irish plant which, following Mitten, has commonly been referred to as Plagiochila ambagiosa Mitt. is specifically different from the type of P. ambagiosa, and is therefore described as Plagiochila atlantica F. Rose, sp. nov. It is now known from very restricted areas in Western Ireland, Western Scotland and North-western France.     

Two new species of <Emphasis Type="Italic">Leptolobium</Emphasis> (Leguminosae,Papilionoideae) from Brazil

Two new species of Leptolobium from Brazil are described and illustrated. Leptolobium araguaiense, restricted to northern Brazil, is similar to L. panamense, but differs in raceme length, ovary pubescence, flower and bract length, hilum shape, habit, geographical distribution, and preferential habitat. Leptolobium multijugum, from midwestern Brazil, is perhaps most closely related to L. glaziovianum, but it has more numerous leaflets and smaller bracts and bracteoles than any other species in the genus.     

Self-pollination,style length development and seed set in self-compatible Asteraceae: evidence from Senecio vulgaris L.

Background: Variation in style length has been reported in Senecio vulgaris and has been associated with outcrossing rate.

Aims: To determine if (i) long styles lack germinated pollen on stigmas left to self-pollinate, (ii) successful self-pollination causes styles to stop elongating and shrink in length and (iii) seed set increases with the amount of pollen deposited on stigmas.

Methods: Determined germinated self-pollen on stigmas of long and short styles after auto-self-pollination; scored style length over 48 h in self-pollinated and non-pollinated florets; recorded seed set after placing different amounts of pollen on stigmas.

Results: Most long-styled florets had zero or low amounts of germinated pollen on stigmas in contrast to most short-styled florets. Styles initially elongated to the same length in self-pollinated and non-pollinated florets, then shrank in length in self-pollinated florets while continuing to elongate in non-pollinated florets. Seed set increased with number of pollen grains deposited on stigmas.

Conclusions: Successful self-pollen deposition and/or germination on stigmas of S. vulgaris are indicated by presence of short styles, whereas the opposite is indicated by presence of long styles in florets left to self-pollinate. Self-pollination causes styles to shrink after initially elongating. Seed set is dependent on the amount of pollen deposited on stigmas.     

Gagea bohemica (Liliaceae), a highly variable monotypic species within Gagea sect. Didymobulbos

Abstract

Gagea bohemica s.l. (Liliaceae) consists of two morphologically extreme forms (saxatilis and bohemica) which depending on the varying opinions of the authors are considered as separate species, subspecies or as a single variable species. In this study, morphological (form and length of perianth segments, pilosity of pedicles and peduncles) and molecular data (cpDNA trnL–trnF IGS) of 55 samples corresponding to 43 populations from Western Europe to the Mediterranean area and eastern Caucasus were investigated. G. bohemica (Zauschn.) Schult. & Schult. f. represents a highly variable monotypic species from both morphological and karyological (2n = 24, 36, 48, 60, 72) aspects. Based on the molecular and morphological data presented here, a differentiation between specific and infraspecific taxa is not possible. We hypothesize that the morphological variability of this species is largely influenced by different site conditions and ploidy level.     

Spin Trapping by Use of N-Tert-Butylhydroxylamine. Involvement of Fenton Reactions

Spin trapping of short-lived R. radicals is done by use of N-tert-butylhydroxylamine (1) and H²O². The hydroxylamine is oxidized to the radical t-BuN(O)H (2) which is converted into the spin trap 2-methyl-2-nitrosopropane (3). Simultaneously, hydroxyl radicals. OH are formed from H²O². The latter radical species abstracts hydrogen atoms from suitable molecules HR to give R. radicals, which are trapped with the formation of aminooxyl radicals, i. e., t-BuN(O)R (4) detectable by EPR spectroscopy. The reaction is enhanced by the presence of iron ions. The cleavage of H²O² into. OH radicals is considered to involve both a radical-driven (t-BuN(O)H 2) and an iron-driven Fenton reaction.     

Pyrus ciancioi (Rosaceae), a new species from Sicily

Abstract

A new species of Pyrus L. from the Nebrodi Mountains (northeast Sicily) is described, named, and illustrated. It differs from Pyrus spinosa in the shape and diameter/length ratio of its fruits and in the width/length ratio of the leaf lamina. An analytical key to the Pyrus species growing in Sicily is provided.     

Folsomia (Collembola: Isotomidae) of China. II. heterocellata group

An annotated list of species of the Folsomia heterocellata group recorded in China is given. Folsomia cephalota n. sp., F. dorsomediaseta n. sp., F. longiseta n. sp., F. manubriopilosa n. sp., F. longdeica n. sp., and F. plenosensilla n. sp. are characterized by having a simple maxillary palp, four prelabral setae and no eyes. They differentiate mainly by characteristics of the furca. We report other species of the group which are recorded for the first time in China: Folsomia tianshanica Martynova, 1969, F. pseudovtorovi Potapov & Gulgenova, 2013, and F. pseudodecemoculata Stebaeva, 1971. This excludes F. wanxianensis Ji, Ding & Chen, 2007, for which we provide morphological remarks based on the type material. The group is mainly distributed in the central part of China (Chongqing, Gansu, southern part of Inner Mongolia, Ningxia and Shaanxi provinces). A key to all blind species with a simple maxillary palp is given.     

Reperti Teratologici in Tulipa Gesneriana L. Var. Spathulata (Bert.)

Summary

Here is described by the author a teratological case of Tulipa Gesneriana L. v. spathulata (Bert.) which is notable for the concomitance of several anomalies in a single individual:

a) irregular number of the leaves;

b) scape ending with three flowers which are anomalous;

c) two from the above mentioned flowers have tetracarpellary pistil;

d) the third flower has an androecium which is formed by three external stames and, besides, by three other stames which are smaller than the first-ones and are also inglobed in a bypertrophic esacarpellary pistill.