scholarly journals Case study of host-pathogen interaction: tomato (Lycopersicon spp.)–tomato powdery mildew (Oidium lycopersici) – a review

2000 ◽  
Vol 36 (No. 4) ◽  
pp. 156-162 ◽  
Author(s):  
A. Lebeda ◽  
B. Mieslerová
Keyword(s):  
Powdery Mildew ◽  
Host Pathogen Interaction ◽  
Molecular Approaches ◽  
Morphological Studies ◽  
Host Pathogen ◽  
Tomato Powdery Mildew ◽  
Oidium Lycopersici ◽  
Pathogenic Variability ◽  
Available Information

  The present paper tries to demonstrate progress and gap of knowledge in plant pathology through the tomato - tomato powdery mildew host-pathogen interaction as a model. Tomato powdery mildew (Oidium lycopersici) has caused serious damages on glasshouse tomato (Lycopersicon esculentum) crops during the last approximately 15 years. Although the absence of tcleomorph stage did not allow exact taxonomic classification of the pathogen, comparative morphological studies using light and scanning electron microscopy revealed that Oidium lycopersici might be included to the Erysiphe sect. Erysiphe (close to Erysiphe aqui­ legiae var. ranunculi). Effective resistance sources to 0. lycopersici were found mainly in wi ld Lycopersicon hirsutum and L. penne/lii (confirmed by testing with four different 0. lycopersici isolates). Available information on the pathogenic variability of 0. lycopersici is given; host range experiments revealed considerable differences in abi lity of different 0. lycopersici isolates to infect cucumber and tobacco. postulating existence of different pathotypcs lformae specialist of pathogen. Similarly, some Lycopersicon spp. genotypes showed remarkable differential reactions with pathogen isolates, indicating existence of different pathogen races. Information regarding recently detected mechanisms and basis of resistance in Lycopersicon spp. are also men­ tioned. However, more research based on classical, biochemical and molecular approaches is also needed.

scholarly journals Toxoplasma Effectors Targeting Host Signaling and Transcription

2017 ◽  
Vol 30 (3) ◽  
pp. 615-645 ◽  
Author(s):  
Mohamed-Ali Hakimi ◽  
Philipp Olias ◽  
L. David Sibley
Keyword(s):  
Host Cells ◽  
Content Type ◽  
Apicomplexan Parasites ◽  
Small Noncoding Rnas ◽  
Dense Granules ◽  
Host Pathogen Interaction ◽  
Morphological Studies ◽  
Specific Host ◽  
Host Pathogen ◽  
Host Signaling

SUMMARY Early electron microscopy studies revealed the elaborate cellular features that define the unique adaptations of apicomplexan parasites. Among these were bulbous rhoptry (ROP) organelles and small, dense granules (GRAs), both of which are secreted during invasion of host cells. These early morphological studies were followed by the exploration of the cellular contents of these secretory organelles, revealing them to be comprised of highly divergent protein families with few conserved domains or predicted functions. In parallel, studies on host-pathogen interactions identified many host signaling pathways that were mysteriously altered by infection. It was only with the advent of forward and reverse genetic strategies that the connections between individual parasite effectors and the specific host pathways that they targeted finally became clear. The current repertoire of parasite effectors includes ROP kinases and pseudokinases that are secreted during invasion and that block host immune pathways. Similarly, many secretory GRA proteins alter host gene expression by activating host transcription factors, through modification of chromatin, or by inducing small noncoding RNAs. These effectors highlight novel mechanisms by which T. gondii has learned to harness host signaling to favor intracellular survival and will guide future studies designed to uncover the additional complexity of this intricate host-pathogen interaction.

scholarly journals QTLs for Tomato Powdery Mildew Resistance (Oidium lycopersici) in Lycopersicon parviflorum G1.1601 Co-localize with Two Qualitative Powdery Mildew Resistance Genes

2003 ◽  
Vol 16 (2) ◽  
pp. 169-176 ◽  
Author(s):  
Yuling Bai ◽  
Cai-Cheng Huang ◽  
Ron van der Hulst ◽  
Fien Meijer-Dekens ◽  
Guusje Bonnema ◽  
...  
Keyword(s):  
Powdery Mildew ◽  
Lycopersicon Esculentum ◽  
Powdery Mildew Resistance ◽  
Hypersensitive Resistance ◽  
Resistance Response ◽  
Mildew Resistance ◽  
Sequence Characterized Amplified Region ◽  
Tomato Powdery Mildew ◽  
Oidium Lycopersici ◽  
Genomic Regions

Tomato (Lycopersicon esculentum) is susceptible to the powdery mildew Oidium lycopersici, but several wild relatives such as Lycopersicon parviflorum G1.1601 are completely resistant. An F2 population from a cross of Lycopersicon esculentum cv. Moneymaker × Lycopersicon parviflorum G1.1601 was used to map the O. lycopersici resistance by using amplified fragment length polymorphism markers. The resistance was controlled by three quantitative trait loci (QTLs). Ol-qtl1 is on chromosome 6 in the same region as the Ol-1 locus, which is involved in a hypersensitive resistance response to O. lycopersici. Ol-qtl2 and Ol-qtl3 are located on chromosome 12, separated by 25 cM, in the vicinity of the Lv locus conferring resistance to another powdery mildew species, Leveillula taurica. The three QTLs, jointly explaining 68% of the phenotypic variation, were confirmed by testing F3 progenies. A set of polymerase chain reaction-based cleaved amplified polymorphic sequence and sequence characterized amplified region markers was generated for efficient monitoring of the target QTL genomic regions in marker assisted selection. The possible relationship between genes underlying major and partial resistance for tomato powdery mildew is discussed.

Initial events in the colonisation of tomatoes by Oidium lycopersici, a distinct powdery mildew fungus of Lycopersicon species

2000 ◽  
Vol 78 (10) ◽  
pp. 1361-1366 ◽  
Author(s):  
Hannah E Jones ◽  
John M Whipps ◽  
Barry J Thomas ◽  
Tim LW Carver ◽  
Sarah J Gurr
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Powdery Mildew ◽  
Intergenic Spacer ◽  
Powdery Mildew Fungus ◽  
Subsequent Formation ◽  
Powdery Mildew Fungi ◽  
Tomato Powdery Mildew ◽  
Oidium Lycopersici ◽  
Scanning Electron

The rDNA intergenic spacer sequence of Oidium lycopersici (ana.; Cooke & Massee 1888, emend. Noordeloos and Loerakker 1989, emend. Mieslerova and Lebeda 1999) was determined and compared with the sequences of other powdery mildews. This pathogen was shown to be distinct from other powdery mildew fungi found on tomato, but it exhibited a close similarity to Erysiphe aquilegiae var. ranunculi. The initial events involved in the germination of conidia and subsequent formation of the appressorium in the newly described powdery mildew of tomato, O. lycopersici, were studied by light and scanning electron microscopy. Scanning electron microscopy revealed the conidial coat to be smooth to slightly rugose and the appressoria to be multilobed and attached to the host by a mucilaginous pad of extracellular material.Key words: Oidium lycopersici, tomato powdery mildew, ITS, life cycle, light microscopy, electron microscopy.

scholarly journals Techniques for Mitigating the Effects of Smoke Taint While Maintaining Quality in Wine Production: A Review

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1672
Author(s):  
Ysadora A. Mirabelli-Montan ◽  
Matteo Marangon ◽  
Antonio Graça ◽  
Christine M. Mayr Marangon ◽  
Kerry L. Wilkinson
Keyword(s):  
Global Perspective ◽  
Wine Industry ◽  
Wine Production ◽  
Specific Data ◽  
Main Research ◽  
Initial Severity ◽  
The Subject ◽  
Available Information

Smoke taint has become a prominent issue for the global wine industry as climate change continues to impact the length and extremity of fire seasons around the world. Although the issue has prompted a surge in research on the subject in recent years, no singular solution has yet been identified that is capable of maintaining the quality of wine made from smoke-affected grapes. In this review, we summarize the main research on smoke taint, the key discoveries, as well as the prevailing uncertainties. We also examine methods for mitigating smoke taint in the vineyard, in the winery, and post production. We assess the effectiveness of remediation methods (proposed and actual) based on available research. Our findings are in agreement with previous studies, suggesting that the most viable remedies for smoke taint are still the commercially available activated carbon fining and reverse osmosis treatments, but that the quality of the final treated wines is fundamentally dependent on the initial severity of the taint. In this review, suggestions for future studies are introduced for improving our understanding of methods that have thus far only been preliminarily investigated. We select regions that have already been subjected to severe wildfires, and therefore subjected to smoke taint (particularly Australia and California) as a case study to inform other wine-producing countries that will likely be impacted in the future and suggest specific data collection and policy implementation actions that should be taken, even in countries that have not yet been impacted by smoke taint. Ultimately, we streamline the available information on the topic of smoke taint, apply it to a global perspective that considers the various stakeholders involved, and provide a launching point for further research on the topic.

scholarly journals Golovinomyces longipes (Noordel. & Loer.) L. Kiss on Matricaria chamomilla L.: another host range expansion

2021 ◽  
Author(s):  
M. Götz ◽  
U. Braun
Keyword(s):  
Sequence Analysis ◽  
Powdery Mildew ◽  
Host Range ◽  
Dna Sequence ◽  
Range Expansion ◽  
Matricaria Chamomilla ◽  
Important Family ◽  
The Past ◽  
Morphological Studies ◽  
Host Range Expansion

AbstractGolovinomyces longipes is a widespread powdery mildew on Solanaceae (Nicotiana, Petunia and Solanum spp.). In the past, it has been reported only once on Verbena (Verbenaceae), a non-solanaceaous host. Recently, this powdery mildew has been found on the composite Matricaria chamomilla. The identification of the powdery mildew species on this unusual host has been proved by morphological studies and DNA sequence analysis. Both datasets coincide with the characteristic data for G. longipes on Solanaceae. First inoculation experiments with further composites resulted in an infection of Brachyscome hybrid ‘Surdaisy’. To our knowledge, this is the first report of G. lonigpes on hosts belonging to the important family of Asteraceae and an additional proof of the broader host range of G. longipes beyond the Solanaceae.

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