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1.
Summary   Linaria khalkhalensis Hamdi & Assadi is described as a new species from Azerbaijan and Guilan provinces (northern Iran), belonging to Linaria sect. Linaria. It is close to Linaria lineolata Boiss. and L. elymaitica (Boiss.) Kuprian., which it resembles in habit and vegetative features. However, floral and seed characters together with a distinctive geographical distribution, warrant recognition at the species rank. An illustration of the new species, a distribution map, scanning electron micrographs of seed and capsule surfaces, and an identification key are also included.  相似文献   

2.
  • Root‐hemiparasitic interaction between the dominant grass Calamagrostis epigejos and the hemiparasite Thesium linophyllon was studied to assess the potential of the parasite to regulate dominance of the grass, which is expanding into species‐rich steppe grasslands.
  • First, we aimed to identify physiological links between the two species as a principal indicator of the parasitic relationship. Second, we analysed the dynamics of the two species in the vegetation of a steppe grassland at the foot of the Bükk Mountains, Hungary, where their joint presence is recorded in a long‐term permanent plot monitoring dataset to detect patterns associated with the parasitic ecological interaction.
  • Numerous well‐developed functional haustoria of Th. linophyllon were identified on the root systems of C. epigejos. The joint dynamics of C. epigejos and Th. linophyllon displayed clear signs of the parasitic interaction: (1) the dynamics of Th. linophyllon frequency was positively associated with the initial cover of C. epigejos; (2) maximum recorded cover values of the two species were strongly positively correlated; and (3) the extent of C. epigejos decrease in the vegetation was significantly positively associated with maximum Th. linophyllon cover recorded throughout the monitoring period.
  • We demonstrate that C. epigejos can be parasitized by Th. linophyllon, which restricts abundance of the grass. Th. linophyllon thus has potential to act as a native biological control of C. epigejos in steppe grasslands.
  相似文献   

3.
4.
To get a better understanding of their taxonomic importance, we examined morphological, leaf epidermal and seed micromorphological characters of 19 taxa of annual Papaver L. belonging to the sections Papaver, Carinatae Fedde and Rhoeadium Spach. Among the studied taxa, the pattern of the coat of the seed testa cells and seed epidermal cell showed large variation. The granulate type of testa sculpturing was most common, but other types were represented by one or two species. In contrast, most of the taxa have broadly similar leaf epidermal characteristics. We conclude that variation in seed characters are significant for the taxonomy at the specific and generic levels, whereas leaf epidermis morphology, with few exceptions, is mostly only useful for separation of taxa within species. Based on the results, P. lacerum Popov is regarded as a synonym of P. commutatum Fisch. & C. A. Mey, while P. piptostigma Bienert ex Fedde, P. halophilum (Fedde) Cullen and P. tubuliferum Fedde are regarded as synonyms of P. macrostomum Boiss. et Huet ex Boiss. var. macrostomum. Further, Papaver gaubae Cullen & Rech. f. and P. bipinnatum C. A. Mey. are included into the synonymy list of P. glaucum Boiss. et Hausskn. and P. arenarium M.‐Bieb., respectively. In contrast, Papaver chelidoniifolium Fisch. & C. A. Mey. var. pinnatum Tavakkoli & Assadi from Gilan province is described as a new variety, and P. rhoeas L. var. strigosum Boenn. and var. glabrum Fedde and P. commutatum subsp. euxinum Kadereit are introduced as new records to Iran. The evolutionary and phylogenetic implications of the observed variation in seed characteristics are also discussed.  相似文献   

5.
Abstract

Laboulbeniales (Ascomycetes) new for Italy. In the present paper are quoted 19 species of Laboulbeniales not jet reported for Italian flora: Asaphomyces cholevae Th., Corethromyces henroti Balazuc, C. pallidus (Th.), C. stilici Th., Euzodiomyces lathrobii Th., Helodiomyces elegans Picard, Laboulbenia acupalpi Speg., L. inflata Th., L. philonthi Th., L. picardi Maire, Misgomyces dyschirii Th., M. lavagnei Picard, Monoicomyces californicus (Th.), Peyritschiella protea Th., Rhachomyces lasiophorus (Th.), R. furcatus (Th.), R. philonthinus Th., R. pilosellus (Robin). Also the genera Asaphomyces Th., Euzodiomyces Th., Helodiomyces Picard and Peyritschiella Th. are new for Italy. All the quoted species are parasites of Insects of the order of the Coleoptera.  相似文献   

6.
 The objective of this study was to detect the presence of alien chromatin in intergeneric hybrids of durum wheat (Triticum turgidum, 2n=4x=28; AABB genomes) with the perennial grass Thinopyrum junceiforme (2n=4x=28; J1J1J2J2) using RAPD markers. The first step was to identify amplification of species-specific DNA markers in the parental grass species and durum wheat cultivars. Initially, the genomic DNA of five grass species (Thinopyrum junceiforme, Th. bessarabicum, Lophopyrum elongatum, Leymus karataviensis and Elytrigia pycnantha) and selected durum cultivars (‘Langdon’, ‘Durox’, ‘Lloyd’, ‘Monroe’, and ‘Medora’) was screened with 40 oligonucleotide primers (nano-mers). Three oligonucleotides that amplified DNA fragments specific to a grass species or to a durum cultivar were identified. Primer PR21 amplified DNA fragments specific to each of the five durum cultivars, and primers PR22 and PR23 amplified fragments specific to each of the grass species. Intergeneric hybrids between the durum cultivars ‘Langdon’, ‘Lloyd’ and ‘Durox’ and Th. junceiforme, and their backcross (BC) progeny were screened with all 40 primers. Six primers amplified parent-specific DNA fragments in the F1 hybrids and their BC1 progeny. Three primers, PR22, PR23 and PR41, that amplified Th. junceiforme DNA fragments in both F1 and BC1 were further analyzed. The presence of an amplified 1.7-kb Th. junceiforme DNA fragment in the F1 hybrids and BC1 progeny was confirmed using Southern analysis by hybridization with both Th. junceiforme genomic DNA and Th. junceiforme DNA amplified with primer PR41. With the exception of line BC1F2 no. 5, five selfed progeny of BC1 and a BC2 of line 3 (BC1F2 no. 3בLloyd’) from a cross of ‘Lloyd’×Th. junceiforme showed the presence of the 1.7-kb DNA fragment. All selfed BC1 and BC2 lines retained the 600-bp fragment that was confirmed after hybridization with Th. junceiforme DNA amplified with primer PR22. Other experiments using RFLP markers also showed the presence of up to seven Th. junceiforme DNA fragments in the F1 hybrids and their BC progeny after hybridization with Th. junceiforme DNA amplified with primer PR41. These studies show the usefulness of molecular markers in detecting alien chromatin/DNA fragments in intergeneric hybrids with durum wheat. Received: 21 November 1996 / Accepted: 21 March 1997  相似文献   

7.
We describe a polymerase chain reaction (PCR)-based test that is specific for the pathogenic European biotype 2 (Th2) and North American biotype 4 (Th4) of Trichoderma harzianum, responsible for the green mold epidemic in the cultivated mushroom, Agaricus bisporus. A PCR primer pair was designed that targets a 444-bp arbitrary sequence in the genome of Th4. The primers also amplified the same product with Th2, but showed no reactivity with other biotypes of T. harzianum, several biocontrol Trichoderma, or with 31 other genera and species of fungi. The PCR-based test should have application in disease management programs, and in the evaluation of biocontrol Trichoderma for potential pathogenicity on mushrooms. Received: 23 November 1998 / Received revision: 19 February 1999 / Accepted: 5 March 1999  相似文献   

8.
9.
The calanoid copepods of the Nile system   总被引:3,自引:3,他引:0  
At least 11 or 12 calanoid taxa occur in the Nile system. One species is typical of the river and of Lake Chad (Th. galebi); two are restricted to Lake Victoria (Th. galeboides, T. stuhlmanni), but both might be only subspecies to more widespread species. One is restricted to Lakes Edward and George (T. worthingtoni) but is a little known species. No calanoids are on record from Lakes Albert and Kyoga, while the species reported from Lake Turkana (T. banforanus) is out of range, and almost certainly represents an erroneous record. Among the remaining species, four are East-African, ranging from the southern tip of the continent to the Ethiopian plateau and the Nile valley (P. schultzei, Th. mixtus, T. kraepelini, T. cf orientalis), while two are Sahelian species that span Africa from east to west (M. mauretanicus, T. processifer et ssp.).Two new synonyms are introduced. One new subspecies (T. processifier friedae) is described from the Ethiopian plateau. It is suggested that Tropodiaptomus orientalis (Brady, 1886), the type species of its genus, should not be considered a nomen dubium, but should be redescribed on its type female(s) and on topotypical males from Sri Lanka.  相似文献   

10.
La Paz Bay and La Paz Lagoon are water bodies of the Gulf of California that are influenced by waste water discharges from the City of La Paz and from activities of the phosphorite mining company “Rofomex”. Because seaweeds concentrate elements from the water and are used as effective indicators of contamination by metals, we investigated their usefulness in this region. Concentrations of certain major elements (Ca, Fe, K and Na) and trace elements (As, Ba, Co, Cr, Cs, Hf, Rb, Sb, Sc, Se, Sr, Ta, Th, U, Zn and Zr) were determined in 12 species of seaweeds from La Paz Bay and La Paz Lagoon using instrumental neutron activation analysis. The contents of trace elements of environmental importance (As, Co, Cr, Fe, Sb, Se and Zn) in all studied samples are within the range of typical levels for a pristine environment not subjected to anthropogenic impact. Somewhat higher concentrations of Cr (81mg kg−1), Hf (4mg kg−1), Rb (48mg kg−1), Sc (6.3mg kg−1), Ta (0.95mg kg−1), Th (6.8mg kg−1), U (33mg kg−1) and Zn (90mg kg−1) were found in the green seaweed species Ulva (formerly Enteromorpha) intestinalis, whereas such elements as As (77mg kg−1), Sb (1.4mg kg−1) and Se (1.8mg kg−1) were mainly concentrated in the species Sargassum sinicola, Codium cuneatum and Padina mexicana respectively. Because of their higher abundance and heterogeneity in elemental composition the seaweeds species Ulva intestinalis and Caulerpa sertularioides seem to be more suitable for further biomonitoring of heavy metal pollution of the coastal waters in this zone.  相似文献   

11.
Thirty-two species of Cicadellidae, including the Macropsinae, Agalliinae, Penthimiinae, Aphrodinae, Cicadellinae, Typhlocybinae and Deltocephalinae, 10 of which were already known as phytoplasma vectors, were captured in vineyards using yellow sticky traps. Adult population dynamics of the most abundant species of Penthimiinae and Deltocephalinae were studied over the whole growing season. Penthimia nigra was captured in May and June, Anoplotettix fuscovenosus in June-August, Fieberiella florii in August-October, Macrosteles sexnotatus in May and October, Scaphoideus titanus in July-September, Thamnotettix spp. (Th. confinis, Th. dilutior, Th. exemtus, Th. zelleri) in April-June, while Euscelidius variegatus, Neoaliturus fenestratus, Platymetopius major and Psammotettix spp. (P. alienus, P. confinis) were trapped throughout the growing season. The aggregation level of the above species was investigated by means of Taylor's power law. A. fuscovenosus showed a nearly random distribution in vineyards (0.95 < b < 1.11), while N. fenestratus, P. major and S. titanus were strongly aggregated (1.32 < b < 1.81). The other species showed intermediate levels of aggregation (1.12 > b < 1.32). The results indicate that at least six Deltocephalinae species, A. fuscovenosus, E. variegatus, F. florii, M. sexnotatus, N. fenestratus and S. titanus, known as phytoplasma vectors and commonly found in vineyards, could play a role in Grapevine Yellows (GY) epidemiology. GY transmission trials with these species are needed.  相似文献   

12.
Collections from high altitudes (3840–5100 m a.s.l.) have added several species to the Pannariaceae of Ecuador: Fuscopannaria praetermissa, Pannaria hookeri, Psoroma paleaceum and Psoroma tenue are new to the Andes, and phytogeographic consequences of these are discussed. The following new taxa are described: Parmeliella corallina P. M. Jørg. & Palice, Parmeliella psoromoides P. M. Jørg. & Palice, Psoroma cinnamomeum ssp. andinum P. M. Jørg. & Palice and Santessoniella macrospora P. M. Jørg. & Palice. They are part of a high‐andean element which is not well known and is indicative of a migration route between the polar regions. In addition, two species with associated cyanobacteria, as the primary or secondary symbiont, are reported for the first time from South America: Thelignya lignyota (Wahlenb.) P. M. Jørg. & Henssen and Pilophorus cereolus (Ach.) Th. Fr, both originating from the Northern Hemisphere.  相似文献   

13.
Jens Lehmann 《Hydrobiologia》1973,43(3-4):381-414
Summary In the preceding paper, a revision of the species of the genusThienemanniola Kieffer is presented. The speciesTh. longipennis Kieffer andTh. brevitarsis Kieffer are declared to be synonymous toTh. ploenensis Kieffer.All three stages of the metamorphosis ofTh. ploenensis are described and figured; ecological notes are also given.The speciesCorynocera ambigua Zetterstedt andCorynocera oliveri Lindeberg are briefly characterized and figured.Finally, the systematical classification of the generaCorynocera andThienemanniola into the familyChironomidae and the degree of relationship between the generaCorynocera andThienemanniola are discussed.  相似文献   

14.
Most experimental studies on leishmaniasis compare two different inbred strains of mice that are resistant or susceptible to one species of Leishmania. In the present study we characterized some cytokines and nitric oxide production as well as histological changes related to resistance and susceptibility in isogenic CBA mice infected with Leishmania major or Leishmania amazonensis. CBA mice are capable of controlling infection with L.  major, but they succumb to infection with L. amazonensis. Cells from susceptible L. amazonensis-infected CBA mice produced interleukin (IL)-4 and IL-10 but no interferon (IFN)-γ. On the other hand, resistant L. major-infected CBA mice produced IFN-γ and IL-10, but IL-4 was detected only in the first week of infection. Histopathological studies showed patterns of tissue responses at the site of the infection and in the draining lymph nodes that correlated with resistance or susceptibility. Resistant mice showed a mixed inflammatory cell infiltration and granulomas in the lesions, whereas in susceptible mice only heavily parasitized macrophages were seen. Our results indicate an important role of the parasite species in determining the pattern of immune response. L. amazonensis induces a Th2-type immune response, whereas L.  major induces a Th1-type response. These factors must be identified and taken into account in the strategies for the development of vaccines against leishmaniasis. The model presented here will be useful for the study of such factors.  相似文献   

15.
 Genomic in situ hybridization (GISH) was used to distinguish autosyndetic from allosyndetic pairing in the hybrids of Thinopyrum intermedium and Th. ponticum with Triticum aestivum cv ‘Chinese Spring’ (CS). All hybrids showed high autosyndetic pairing frequencies among wheat chromosomes and among Thinopyrum chromosomes. The high autosyndetic pairing frequencies among wheat chromosomes in both hybrids suggested that Th. intermedium and Th. ponticum carry promoters for homoeologous chromosome pairing. The higher frequencies of autosyndetic pairing among Thinopyrum chromosomes than among wheat chromosomes in both hybrids indicated that the relationships among the three genomes of Th. intermedium and among the five genomes of Th. ponticum are closer than those among the three genomes of T. aestivum. Received: 19 September 1996 / Accepted: 18 April 1997  相似文献   

16.
Twenty-five partial amphiploids (2n=8x=56), which were derived from hybrids of wheat (Triticum aestivum L.) with either Thinopyrum ponticum (Podpera) Liu & Wang, Th. intermedium (Host) Barkworth & D. Dewey, or Th. junceum (L.) A. Löve, were assayed for resistance to BYDV serotype PAV by slot-blot hybridization with viral cDNA of a partial coat protein gene. Three immune lines were found among seven partial amphiploids involving Th. ponticum. Seven highly resistant lines were found in ten partial amphiploids involving Th. intermedium. None of eight partial amphiploids or 13 addition lines of Chinese Spring — Th. junceum were resistant to BYDV. Genomic in situ hybridization demonstrated that all of the resistant partial amphiploids, except TAF46, carried an alien genome most closely related to St, whether it was derived from Th. ponticum or Th. intermedium. The two partial amphiploids carrying an intact E genome of Th. ponticum are very susceptible to BYDV-PAV. In TAF46, which contains three pairs of St- and four pairs of E-genome chromo somes, the gene for BYDV resistance has been located to a modified 7 St chromosome in the addition line L1. This indicates that BYDV resistance in perennial polyploid parents, i.e., Th. ponticum and Th. intermedium, of these partial amphiploids is probably controlled by a gene(s) located on the St-genome chromosome(s).  相似文献   

17.
18.
该文采用形态解剖、化学及生态等传统分类方法,以及显色反应(CT)、薄层层析(TLC)等生物化学方法,对新疆天山南麓巴音布鲁克山区和天山中部米泉哈熊沟泡鳞衣属地衣进行了分类学研究,并鉴定采样区泡鳞衣属的地衣种类。结果表明:共鉴定出似皮革泡鳞衣Toninia alutacea(Anzi)Jatta、兰黑泡鳞衣T.caeruleonigricans(Lightf.)Th.Fr.、白泡鳞衣T.candida(Weber)Th.Fr.、泡状泡鳞衣T.physaroides(Opiz)Zahlbr.、暗色泡鳞衣中亚亚种T.tristis subsp.asiae-centralis(H.Magn.)Timdal等5个种,其中2个为中国新记录种:似皮革泡鳞衣T.alutacea和泡状泡鳞衣T.physaroides;同时描述了5个种的形态解剖特征、化学特征及其生境,并提供了相关彩色图片和新疆泡鳞衣属地衣检索表。研究结果可为新疆地衣的研究提供实验数据,为中国泡鳞衣属研究提供科学依据。  相似文献   

19.
20.
Thinopyrum distichum is indigenous to the southern and south western coastal shores of South Africa. Like many of the Thinopyrum species it can be hybridized with wheat. The resulting progeny treated with colchicine produce fertile amphiploids. The need to distinguish the Th. Distichum chromosomes from one another and from those of wheat prompted the investigation of the C-band distribution. The chromosome pairs of Th. distichum were distiguishable from each other and from those of wheat using C-band patterns, morphology and size as identification criteria. The chromosomes ranged from heterobrachial to metacentric with interstitial and telomeric C-bands. The C-band patterns of Th. distichum were similar, but not identical, to those of other Thinopyrum species.  相似文献   

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