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2023 ◽  
Vol 83 ◽  
Author(s):  
P. S. Silva ◽  
V. A. Royo ◽  
H. M. Valerio ◽  
E. G. Fernandes ◽  
M. V. Queiroz ◽  
...  

Abstract Interactions between endophytic fungi (EFs) and their host plants range from positive to neutral to negative. The results of such interactions can vary depending on the organ of the infected host plant. EFs isolated from the leaves of some species of plants have potential for use as agents to inhibit seed germination and control invasive plants. The objectives of this study were to identify EFs present in the leaves of Copaifera oblongifolia and to evaluate the role of these fungi in seed germination and seedling development. A total of 11 species of EFs were isolated, which were identified using the internal transcribed spacers (ITS) sequence of the nuclear ribosomal DNA. The isolated species of EFs are generalists and probably are transmitted horizontally. Laboratory tests revealed that filtrates of these fungal isolates differently affect seed germination and seedling development of C. oblongifolia. The species Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum and Phomopsis sp. negatively affected seed germination, with N. parvum standing out for its negative effects, inhibiting seedling germination and survival in 89 and 222%, respectively. In addition, Cochliobolus intermedius negatively affected seedling development. Thus, the combined use of N. parvum and C. intermedius, or products from the metabolism of these microorganisms, in the control of invasive plants deserves attention from future studies.


2022 ◽  
Vol 9 ◽  
Author(s):  
Wei-Hua Cui ◽  
Xin-Yu Du ◽  
Mi-Cai Zhong ◽  
Wei Fang ◽  
Zhi-Quan Suo ◽  
...  

Abstract While roses are today among the most popular ornamental plants, the petals and fruits of some cultivars have flavored foods for millennia. The genetic origins of these edible cultivars remain poorly investigated. We collected the major varieties of edible roses available in China, assembled their plastome sequences, and phased the haplotypes for internal transcribed spacers (ITS1/ITS2) of the 18S-5.8S-26S nuclear ribosomal cistron. Our phylogenetic reconstruction using 88 plastid genomes, of primarily maternal origin, uncovered well-supported genetic relationships within Rosa, including all sections and all subgenera. We phased the ITS sequences to identify potential donor species ancestral to the development of known edible cultivars. The tri-parental Middle-Eastern origin of R. × damascena, the species most widely used in perfume products and food additives, was confirmed as a descendent of past hybridizations among R. moschata, R. gallica, and R. majalis/R. fedtschenkoana/R. davurica. In contrast, R. chinensis, R. rugosa, and R. gallica, in association with six other wild species, were the main donors for fifteen varieties of edible roses. The domesticated R. rugosa ‘Plena’ was shown to be a hybrid between R. rugosa and R. davurica, sharing a common origin with R. ‘Fenghua’. Only R. ‘Jinbian’ and R. ‘Crimson Glory’ featured continuous flowering. All remaining cultivars of edible roses bloomed only once a year. Our study provides important resources for clarifying the origin of edible roses and suggests a future for breeding new cultivars with unique traits, such as continuous flowering.


2021 ◽  
Vol 78 (2) ◽  
pp. e116
Author(s):  
Mike Thiv ◽  
Manuela Gouveia ◽  
Miguel Menezes de Sequeira

Macaronesian laurel forests harbour many herbs and laurophyllous trees with Mediterranean/European or Macaronesian affinities. Traditionally, the origin of these taxa has been explained by the relict hypothesis interpreting these taxa as relics of formerly widespread laurel forests in the European continent and the Mediterranean. We analysed the phylogenetic relationships of the Madeiran laurel forest endemic Goodyera macrophylla (Orchidaceae) using sequences from the nuclear ribosomal DNA Internal Transcribed Spacers (ITS) and plastid DNA regions. The results were incongruent, either the two Central American G. brachyceras and G. striata (ITS) or the North American G. oblongifolia (plastid DNA) were sister group to G. macrophylla. Nonetheless, biogeographic analyses indicated an American origin of this nemoral laurel forest plant in the two data sets. Molecular clock analyses suggest a colonisation of Madeira in the span of the upper Miocene/lower Pliocene to the Pleistocene. Although the relict hypothesis cannot be ruled out by our data when assuming extinction events on the European and northern African mainland, dispersal from Central or North America to the archipelago of Madeira is a much more likely explanation of the data.


2021 ◽  
Vol 16 (4) ◽  
pp. 399-420
Author(s):  
Majid Bannai ◽  
◽  
Muna Mohammed Jori ◽  
Shokoofeh Shamsi ◽  
◽  
...  

The present study provides a new insight into valuable information on the diverse structure of the Anisakid population and discusses the limited species richness in the Nemipterus japonicus (Bloch,1791) (Perciformes, Nemiperidae). The fishing area consists of various locations in the Arabian Gulf (29°58 0 33 00 N48°28 0 20 E). A total of 315 marine fish were examined, (n=287) were infected. Larval stages (n= 763) encysted within the mesenteries peritoneum and viscera of fish organs were isolated, with a prevalence of 91.11% of infection and, the intensity was 2.65. Molecular analysis was carried out on thirty individuals who have examined the morphology and showed some appearance differences, by amplifying internal transcribed spacers ITS and ITS-1 of nuclear rDNA (rDNA) by PCR using the primer sets NC5/NC2 and SS1/NC13R of thirteen DNA products. Evolutionary analyses were conducted in MEGA X. based on the identity percentage in the GenBank database showed that they belong to anisakid nematodes, in particular, they belong to eleven distinct taxa within the Hysterothylacium Ward & Magath, 1917 (Rhabditida, Raphidascarididae) and one identified species H. amoyense (Hsü, 1933) Deardorff & Overstreet, 1980. The current study records eleven species that belong to a genus of Hysterothylacium; some of the alignment of sequences polymorphisms reveals new different individuals of larvae species that may be adopted as new species if their adult stage is detected, and N. japonicus fish considered as a new host record. The current study provides some insights on the systematic taxonomy of these parasites, in addition, it supports similar studies that have been published elsewhere.


MycoKeys ◽  
2021 ◽  
Vol 85 ◽  
pp. 1-30
Author(s):  
Min Qiao ◽  
Hua Zheng ◽  
Ji-Shu Guo ◽  
Rafael F. Castañeda-Ruiz ◽  
Jian-Ping Xu ◽  
...  

The family Microthyriaceae is represented by relatively few mycelial cultures and DNA sequences; as a result, the taxonomy and classification of this group of organisms remain poorly understood. During the investigation of the diversity of aquatic hyphomycetes from southern China, several isolates were collected. These isolates were cultured and sequenced and a BLAST search of its LSU sequences against data in GenBank revealed that the closest related taxa are in the genus Microthyrium. Phylogenetic analyses, based on the combined sequence data from the internal transcribed spacers (ITS) and the large subunit (LSU), revealed that these isolates represent eight new taxa in Microthyriaceae, including two new genera, Antidactylariagen. nov. and Isthmomycesgen. nov. and six new species, Antidactylaria minifimbriatasp. nov., Isthmomyces oxysporussp. nov., I. dissimilissp. nov., I. macrosporussp. nov., Triscelophorus anisopterioideussp. nov. and T. sinensissp. nov. These new taxa are described, illustrated for their morphologies and compared with similar taxa. In addition, two new combinations are proposed in this family.


2021 ◽  
Author(s):  
◽  
Joe Buchanan

<p>Genetic variation in Carpophyllum Greville and Cystophora J. Agardh (Fucales, Phaeophyceae) was investigated at a variety of scales. An extensive survey of mitochondrial spacer variation in Carpophyllum maschalocarpum from 32 populations around New Zealand shows strong population differentiation at relatively small scales (50–100 kilometres), but also pathways of long distance dispersal that connect populations over much greater distances. In addition, historical climate change appears to have restricted C. maschalocarpum to the northern North Island during the last glacial maximum, with subsequent southward range expansion revealed by low genetic diversity in southern populations. These results are consistent with limited dispersal at the gamete and zygote stage, expected in fucalean algae, but with occasional long distance dispersal by detached floating thalli. The genetic signature suggests these two modes of dispersal are decoupled. Internal Transcribed Spacers sequences show little differentiation between C. maschalocarpum and C. angustifolium, and hybridisation was found in several populations where these species are broadly sympatric. In the Bay of Plenty the two species had different ITS ribotypes, but most C. angustifolium specimens had a mitochondrial spacer haplotype that clustered with C. maschalocarpum haplotypes. This indicates mitochondrial introgression from C. maschalocarpum into C. angustifolium. In Northland species were difficult to separate by morphology or molecular markers, and some populations appear to be comprised entirely of hybrids. Genetic distances between different species of Cystophora are very variable, and in some cases intra-species distances are similar to interspecies distances. This is problematic for DNA barcoding methods that rely on thresholds between inter-species and intra-species genetic distances. In some (but not all) cases, the absence of molecular differentiation can be attributed to oversplitting of Cystophora species by morphological methods, and I synonymise C. congesta with C. retroflexa, and C. distenta with C. scalaris. These studies exemplify the difficulties of delimiting species in brown algae: Morphology is often misleading or uninformative; genetic differentiation of species is very variable and often low; and species’ histories show complex patterns of isolation and secondary contact. I argue for an explicitly historical concept of species, with species’ history included in species descriptions.</p>


2021 ◽  
Author(s):  
◽  
Joe Buchanan

<p>Genetic variation in Carpophyllum Greville and Cystophora J. Agardh (Fucales, Phaeophyceae) was investigated at a variety of scales. An extensive survey of mitochondrial spacer variation in Carpophyllum maschalocarpum from 32 populations around New Zealand shows strong population differentiation at relatively small scales (50–100 kilometres), but also pathways of long distance dispersal that connect populations over much greater distances. In addition, historical climate change appears to have restricted C. maschalocarpum to the northern North Island during the last glacial maximum, with subsequent southward range expansion revealed by low genetic diversity in southern populations. These results are consistent with limited dispersal at the gamete and zygote stage, expected in fucalean algae, but with occasional long distance dispersal by detached floating thalli. The genetic signature suggests these two modes of dispersal are decoupled. Internal Transcribed Spacers sequences show little differentiation between C. maschalocarpum and C. angustifolium, and hybridisation was found in several populations where these species are broadly sympatric. In the Bay of Plenty the two species had different ITS ribotypes, but most C. angustifolium specimens had a mitochondrial spacer haplotype that clustered with C. maschalocarpum haplotypes. This indicates mitochondrial introgression from C. maschalocarpum into C. angustifolium. In Northland species were difficult to separate by morphology or molecular markers, and some populations appear to be comprised entirely of hybrids. Genetic distances between different species of Cystophora are very variable, and in some cases intra-species distances are similar to interspecies distances. This is problematic for DNA barcoding methods that rely on thresholds between inter-species and intra-species genetic distances. In some (but not all) cases, the absence of molecular differentiation can be attributed to oversplitting of Cystophora species by morphological methods, and I synonymise C. congesta with C. retroflexa, and C. distenta with C. scalaris. These studies exemplify the difficulties of delimiting species in brown algae: Morphology is often misleading or uninformative; genetic differentiation of species is very variable and often low; and species’ histories show complex patterns of isolation and secondary contact. I argue for an explicitly historical concept of species, with species’ history included in species descriptions.</p>


2021 ◽  
Author(s):  
◽  
Mei Lin Tay

<p>Phylogenetic analyses using molecular data were used to investigate biogeographic and evolutionary patterns of Australasian Plantago. The Internal Transcribed Spacers (ITS) from nuclear DNA, ndhF-rpl32 from chloroplast DNA and cox1 from mitochondrial DNA were selected from a primer assay of 24 primer pairs for further phylogenetic analyses. Phylogenetic reconstruction and molecular dating of a dataset concatenated from these regions comprising 20 Australasian Plantago species rejected a hypothesis of Gondwanan vicariance for the Australasian group. The phylogeny revealed three independent dispersal events from Australia to New Zealand that match expected direction because of West Wind Drift and ocean currents. Following this study, a dataset with 150 new ITS sequences from Australasian Plantago, combined with 89 Plantago sequences from previous studies, revealed that the New Zealand species appear to have a recent origin from Australia, not long after the formation of suitable habitats formed by the uplift of the Southern Alps (about 5 mya), followed by radiation. The ITS phylogeny also suggests that a single migration event of alpine species to lowland habitats has occurred and that recurrent polyploidy appears to be an important speciation mechanism in the genus. Species boundaries between New Zealand Plantago were unclear using both morphological and molecular data, which was a result of low genetic divergences and plastic morphology. The taxonomy of several New Zealand Plantago species need revision based on the ITS phylogeny.</p>


2021 ◽  
Author(s):  
Cornelius Kibet Kipyegen ◽  
Charles I. Muleke ◽  
Elick O. Otachi

Abstract Fasciolosis is a neglected trematode infection of public health and veterinary importance caused by Fasciola gigantica and Fasciola hepatica. Molecular analysis using the internal transcribed spacers’ ITS-1 and ITS-2 of nuclear ribosomal DNA is useful in distinguishing Fasciola species. This study aimed to characterize liver flukes from sheep, goats and cattle using these genetic markers. Fifty nine adult Fasciola specimens were collected from livers of naturally infected sheep, goats and cattle at selected abattoirs in Kisumu, Baringo and Narok Counties. Sequence comparison of ITS-1 and ITS-2 sequences of Fasciola isolates from this study and sequences in Genbank was carried out. A maximum likelihood tree was constructed for phylogenetic analysis. Analysis of ITS-1 and ITS-2 rDNA sequences revealed that F. hepatica and F. gigantica caused infection in both cattle and sheep and in goats only F. gigantica caused infection. The sequenced PCR amplicons showed a close relationship between Fasciola species in this study with Fasciola isolates from other regions in the world. Phylogenetic analysis showed that sequences of F. hepatica are similar to the sequence from Spain, China and Tunisia obtained from GenBank. The sequences of F. gigantica in this study have similarity to the sequence from Iran and Burkina Faso. Data from this study provides information that serves as basis for further studies on the distribution of F. gigantica and F. hepatica in other localities in Kenya, and is also important in designing epidemiological and control programmes for zoonotic fascioliasis.


2021 ◽  
Author(s):  
◽  
Mei Lin Tay

<p>Phylogenetic analyses using molecular data were used to investigate biogeographic and evolutionary patterns of Australasian Plantago. The Internal Transcribed Spacers (ITS) from nuclear DNA, ndhF-rpl32 from chloroplast DNA and cox1 from mitochondrial DNA were selected from a primer assay of 24 primer pairs for further phylogenetic analyses. Phylogenetic reconstruction and molecular dating of a dataset concatenated from these regions comprising 20 Australasian Plantago species rejected a hypothesis of Gondwanan vicariance for the Australasian group. The phylogeny revealed three independent dispersal events from Australia to New Zealand that match expected direction because of West Wind Drift and ocean currents. Following this study, a dataset with 150 new ITS sequences from Australasian Plantago, combined with 89 Plantago sequences from previous studies, revealed that the New Zealand species appear to have a recent origin from Australia, not long after the formation of suitable habitats formed by the uplift of the Southern Alps (about 5 mya), followed by radiation. The ITS phylogeny also suggests that a single migration event of alpine species to lowland habitats has occurred and that recurrent polyploidy appears to be an important speciation mechanism in the genus. Species boundaries between New Zealand Plantago were unclear using both morphological and molecular data, which was a result of low genetic divergences and plastic morphology. The taxonomy of several New Zealand Plantago species need revision based on the ITS phylogeny.</p>


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