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Ana Alfaro-Fernández Mercedes Verdeguer Francisco Rodríguez-León Isabel Ibáñez Desamparados Hernández Gabriela R. Teresani Edson Bertolini Mariano Cambra María Isabel Font 《European journal of plant pathology / European Foundation for Plant Pathology》2017,147(1):15-20
Currently, the main arthropod vectored pathogens associated with carrot and celery crop diseases are ˋCandidatus Liberibacter solanacearum´, Spiroplasma citri and different phytoplasma species. Mitigation strategies require elucidating whether these pathogens survive in the weeds of these Apiaceae crops, which can act as reservoirs. Weed surveys were conducted in a vegetative cycle (April to October 2012) in the spontaneous vegetation that surrounded crops affected by ˋCa. L. solanacearum´, S. citri and/or phytoplasmas. Sixty-three species of 53 genera that belong to 23 botanical families were collected in the main carrot and celery Spanish production area. Species were identified, estimating coverage and abundance, and conserved in herbarium. Samples were analysed by nested-PCR with universal primers for phytoplasmas detection, and were sequenced for identification purposes; by conventional PCR for S. citri and real-time PCR for ˋCa. L. solanacearum´. The only detected pathogens were ˋCa. Phytoplasma trifolii´ (clover proliferation group 16Sr VI-A) in Amaranthus blitoides and Setaria adhaerens and ˋCa. P. solani´ (stolbur group 16Sr XII-A) in Convolvulus arvensis. These pathogens were also sporadically detected in celery or carrot crops. Unexpectedly, neither ˋCa. L. solanacearum´ nor S. citri was detected in the weed samples, despite the relatively high prevalence of these pathogens (less than 66 % and 25 %, respectively) in the surveyed plots. This suggests that weeds do not play an epidemiological role as reservoirs in the spread of such organisms in the studied region. The use of pathogen-free seed lots and the control of vectors are crucial for preventing the introduction and spread of these economical important pathogens to new areas. 相似文献
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Stefan G.R. Wirsel Ralf T. Voegele Reto Bänninger Kurt W. Mendgen 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(8):767-777
The obligate biotrophic nature of rust fungi calls for an in planta selection scheme as a means of developing a rust transformation technology. We show that the fungicides benomyl (used as its formulated product benlate) and carboxin suppress morphogenesis of the rust fungus Uromyces fabae
in vitro and disease in planta, the latter without affecting the health of the host. The limits of their applicability were determined regarding concentration, method of application and optimal time intervals of treatment. Besides procedures for selection, a stable transformation system will also need to include genetic markers allowing to enrich for transformed cells within a large background of untransformed cells. Since the molecular targets of benlate and carboxin had been identified as -tubulin and succinate dehydrogenase, respectively, the corresponding genes (Uf-TBBIand Uf-SUCDHI) were cloned and characterized. Molecular phylogenies demonstrate that both are typical homologs to those of other Basidiomycota. RT-PCR analysis confirmed that both genes are constitutively expressed in all developmental stages of the mitotic uredospore multiplication cycle. Since homologs of Uf-TBB1and Uf-SUCDH1 have been successfully used as selection markers in other fungal systems, they provide valuable tools to develop additional corner stones of a stable transformation system for rust fungi. 相似文献
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Naoya Urasaki Shinji Kawano Hiroyuki Mukai Takashi Uemori Osamu Takeda Teruo Sano 《Journal of General Plant Pathology》2008,74(2):151-155
We developed a detection method for “Candidatus Liberibacter asiaticus”, causal agent of citrus huanglongbing, using isothermal and chimeric primer-initiated amplification
of nucleic acids combined with cycling probe technology (Cycleave ICAN). With Cycleave ICAN, the reaction was done in one
tube in 1 h without the need for electrophoresis, and false positives were not generated. In addition, Cycleave ICAN method
was more sensitive than the conventional PCR method. Cycleave ICAN helps shorten the time for the large-scale detection needed
to manage huanglongbing. 相似文献
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The Rhizoctonia solani species consists of multinucleate isolates that belong to anastomosis groups AG1–AG3 and differ in virulence and host affinity. R. cerealis is a binucleate species of anastomosis group AG-D which causes sharp eyespot, a common plant disease in Poland. Rhizoctonia spp. is a ubiquitous soil pathogen that poses a significant threat for global crop production due to the absence of effective crop protection products. The aim of this study was to determine the virulence of R. solani and R. cerealis isolates towards Beta vulgaris, Zea mays, Triticum spelta and T. aestivum seedlings, to confirm the presence of endopolygalacturonase genes pg1 and pg5 in the genomes of the tested isolates and to evaluate the tested isolates’ sensitivity to triazole, strobilurin, imidazole and carboxamide fungicides. All tested isolates infected B. vulgaris seedlings. but none of them were virulent against Z. mays plants. R. solani isolates AG4 PL and AG2-2IIIB PL were characterized by the highest virulence (average infestation score of 2.37 and 2.53 points on a scale of 0–3 points) against sugar beet seedlings. The prevalence of infections caused by most of the analysed isolates (in particular R. solani AG4 J—11.8, and R. cerealis RC2—0.78) was higher in spelt than in bread wheat. The virulence of the analysed isolates was not correlated with the presence of pg1 and pg5 genes. The efficacy of the tested fungicides in controlling Rhizoctonia spp. infections was estimated at 100% (propiconazole + cyproconazole), 98.8% (penthiopyrad), 95.4% (tebuconazole) and 78.3% (azoxystrobin). 相似文献
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Anna Berlin A.-C. Wallenhammar B. Andersson 《European journal of plant pathology / European Foundation for Plant Pathology》2018,151(4):901-917
The fungus Puccinia coronata Corda. is the causal agent of crown rust on oats (Avena sativa) and grasses and the disease is a major problem in oat production causing devastating yield losses. The population biology of P. coronata in oat fields and on the aecial host in central Sweden was studied to get a deeper understanding of the role of the aecial hosts in the epidemiology of the disease. Samples were collected from the aecial hosts common buckthorn (Rhamnus cathartica) and alder buckthorn (Frangula alnus), and three adjacent spring oat (Avena sativa) fields. Microsatellite markers were used to evaluate the relationships between populations sampled from the different hosts. According to our results F. alnus can be excluded as a part of the oat crown rust disease cycle. The results further show that samples collected from the aecial host were genetically separate from the population sampled in adjacent oat fields. Concurrently, the genotypic variation of P. coronata observed within oat fields was high. No population differentiation was observed within or between samples collected from different fields within the region, suggesting that airborne spores from other than the sampled specimens of the aecial hosts were contributing to the genetic diversity of P. coronata f. sp. avenae in the selected oat fields. 相似文献
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Integrated control of soil-borne plant pathogens such as Sclerotinia sclerotiorum is becoming more important as the soil fumigant methyl bromide is being phased out of use. Two alternative methods of control
that have been found to reduce viability of sclerotia are steam sterilisation (pasteurisation) of soil or the application
of the mycoparasite Coniothyrium minitans. This work investigated the possibility of integrating these two control measures. Soil was pasteurised in an autoclave,
using a temperature of 80 °C for 3 min to simulate the possible temperatures reached by soil steaming machines for field use.
Coniothyrium minitans was subsequently applied to the pasteurised soil to assess the effects of the combination of control measures in reducing
sclerotial viability of S. sclerotiorum. Similar results were found in two soil types. Either method used individually was effective in decreasing the number of
viable sclerotia, but no further reduction in sclerotial viability was seen when the two methods were combined. Coniothyrium minitans was found to colonise pasteurised sclerotia significantly quicker than untreated sclerotia, and it was seen that there was
an increase in number of C. minitans in pasteurised soil in the presence of sclerotia. Experiments were also conducted to investigate the effect of application
timing of the biocontrol agent to soil following pasteurisation, in relation to sclerotial infection. Here, two different
isolates of S. sclerotiorum were used, with similar results. Application of C. minitans to soil immediately following pasteurisation resulted in sclerotial infection by the mycoparasite, but application 7 days
or more after soil pasteurisation resulted in low recovery of the biocontrol agent from sclerotia, possibly due to the mycoparasite
being masked by the presence of other fungi which colonised the sclerotia first. 相似文献
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Phosphorus (P) is the second major plant nutrient required for plant growth. Different sources of water soluble P have been used to increase growth and yield of legumes. In addition, mycorrhizas have a potential role in increasing soil P supply. A factorial experiment was conducted to evaluate the effect of different phosphorus sources (monoammonium phosphate, monopotassium phosphate, urea phosphate, calcium superphosphate and phosphate rock fortified Bacillus megaterium) and arbuscular mycorrhizal inoculation (with or without) on growth and productivity of snap bean (Phaseolus vulgaris L.) cv. Paulista in plastic bags filled with sandy soil during 2014 and 2015 seasons at the Experimental Research Farm of the Horticulture Department, Faculty of Agriculture, Ain Shams University, Qalyubia Governorate, Egypt. The experiment was laid out in a completely randomized design with three replications. Results revealed that fertilization with monoammonium phosphate (MAP) significantly increased vegetative growth characteristics, yield, and total carbohydrates and protein content in green pods concomitantly with increases in chlorophyll and nutrients content in the leaves. Moreover, arbuscular-mycorrhizal inoculation significantly increased all above mentioned data compared with non-mycorrhizal inoculation. In addition, plants inoculated with arbuscular mycorrhizal and fertilized with MAP showed a synergistic effect. 相似文献
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Marta Brylińska Sylwester Sobkowiak Emil Stefańczyk Jadwiga Śliwka 《European journal of plant pathology / European Foundation for Plant Pathology》2018,152(1):33-44
Late blight is a devastating potato disease caused by Phytophthora infestans. This organism can reproduce asexually and sexually between the strains of two mating types named A1 and A2. Mating type is an important strain characteristic affecting the pathogen’s population structure. We validate different PCR markers for P. infestans mating type determination by comparison of the results obtained with the markers (W16, S1, PHYB) with the pairing test results for 26 isolates collected worldwide and for a group of 146 Polish isolates. This study identifies an interesting feature of the isolates of genotype US-1. For all these A1 mating type isolates, the product specific for A2 isolates is amplified using the marker W16. Analysis of sequences of W16 PCR products indicates high similarity of the US-1 isolates with modern A2 mating type isolates. When US-1 isolates are excluded from analysis, 95 and 96% of isolates are correctly assigned by markers W16 and S1, respectively, when compared with the pairing test results. Marker PHYB produces 14% of discrepant results with the pairing test. Our results show that molecular markers can be useful tools for P. infestans mating type determination, but their application should be preceded by validation in each local population since their efficiency may vary depending on a pathogen’s genotype. 相似文献
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Jinu Eo Shuhei Takemoto Kazunori Otobe 《European journal of plant pathology / European Foundation for Plant Pathology》2011,130(2):231-237
We investigated if rates of propagation and migration were related with the level of virulence in the pinewood nematode Bursaphelenchus xylophilus using 17 offspring lines from the F2 crosses between virulent and avirulent isolates. Virulence was tested by inoculating seedlings of Pinus thunbergii with the nematodes. The proportion of dead seedlings ranged from 13.3% to 77.8%, 20 weeks after inoculation. Migration rate
of the nematodes was estimated by measuring their migration distance per unit time in an artificial substrate that imitated
pathways in pine trees. Migration rate varied from 0.85 to 3.53 mm min−1. Propagation rate was determined based on population growth on the fungus Botrytis cinerea, and it ranged between 103.88 and 104.99 per 12 days. Statistical analyses revealed that virulence was not correlated with migration rate, but was negatively correlated
with propagation rate on Botrytis cinerea, suggesting that the nematodes paid some cost for virulence. Also, there was no relationship between rates of migration and
propagation. Cluster analysis showed that the biological parameters varied between crossbred lines, with no kinship bias,
suggesting the absence of sex-linked inheritance in virulence and rates of propagation and migration. 相似文献
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Ömer Erincik Zahide Özdemir Ömer Faruk Durdu Mustafa Timur Döken Serap Açıkgöz 《European journal of plant pathology / European Foundation for Plant Pathology》2011,129(4):555-566
In this study, the population structure of the chestnut blight fungus Cryphonectria parasitica in the Aydın Mountains was investigated to make inferences about fungal reproduction and population diversity. A total of
213 C. parasitica isolates from eight subpopulations were used to determine vegetative compatibility (vc) and mating types of the population.
Furthermore geostatistical analysis was performed to define the spatial structure of the population. The results showed that
the isolates were vegetatively compatible with the European vc types of either EU-1 or EU-12. Both vc types were found in
almost all subpopulations, but their frequencies varied depending on location. The results of a PCR assay showed that both
mating types of C. parasitica (MAT-1 and MAT-2) exist in the population. MAT-1 comprised 65% of the total isolates, and the ratio of mating types was significantly skewed from 1:1. Genotyping based on
combined vc and mating type data revealed four genotypes: EU-1/MAT-1 (28.6%), EU-1/MAT-2 (34.7%), EU-12/MAT-1 (36.2%) and EU-12/MAT-2 (0.5%). Geostatistatical analysis indicated that vc types, mating types and vc/mating genotypes were spatially autocorrelated
and clustered in their distributions. Results suggested that C. parasitica could have a clonal population structure that is generated by asexual reproduction. Low vc-type diversity suggests that the
C. parasitica population in the Aydın Mountains may be highly suitable to hypovirus invasion, thereby providing a high potential for successful
biological control. However, co-occurrence of sexually compatible strains of EU-1 and EU-12 at the same locations in close
proximity creates a high risk of increase in vc-type diversity. 相似文献
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Artemis Rumbou Susanne von Bargen Carmen Büttner 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(3):527-532
The wide natural incidence of Cherry leaf roll virus (CLRV) in deciduous forest trees and nurseries in northern Europe is believed to have occurred, apart from occasional mechanical
spread and transmission through grafting, mainly by seed transmission. The mode of the vertical transmission and its role
in the epidemiology of the virus has not been investigated, basically due to the inconvenient host-pathogen combinations studied
to date. With the aim of obtaining an appropriate system for identification of viral genes and products participating in infection
processes and seed transmission of CLRV, we performed infection and seed transmissibility tests with CLRV in Arabidopsis thaliana plants. Two phylogenetically and serologically different CLRV isolates were tested. Both of them were found able to infect
A. thaliana plants, exhibited clear symptoms of the infection and spread systemically in the plants. Infection of the seeds and of a
remarkable number of seedlings generated from infected seeds was possible for two consecutive generations. These results,
for first time, report seed transmission of CLRV in the model plant A. thaliana and allow the assumption to be made of embryo invasion during seed transmission. Furthermore, first indications are given
that genetically diverse CLRV isolates exhibit different abilities for vertical transmission in A. thaliana. The CLRV-A. thaliana model system is suitable for investigating viral invasion of developing plant organs and meristematic tissue, a prerequisite
for successful virus dissemination via vertical transmission through seed. 相似文献
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Marília Horta Paula Caetano Clara Medeira Isabel Maia Alfredo Cravador 《European journal of plant pathology / European Foundation for Plant Pathology》2010,127(3):427-436
The virulence of two wild type (PA45 and PA37) and two genetically modified (13C: hygromycin resistant; FATSS: hygromycin
resistant and β-cin knock-down) Phytophthora cinnamomi strains towards cork oak (Quercus suber) was assessed via a quantitative evaluation of disease symptoms arising from a soil infestation assay, and by a histological
analysis of root colonization. Comparison of virulence, as expressed by symptom severity, resulted in the following ranking:
highly virulent (wild type strains), medium virulence (strain 13C) and weakly virulent (FATSS). Both transgenic strains were
compromised in their virulence, as expressed by symptom severity, but strain 13C was much less affected than FATSS. Microscopic
observation showed that the FATSS strain was unable to effectively invade the root, while 13C and the two wild type strains
were all able to rapidly colonize the whole root, including the vascular tissue. These results strengthen the notion that
elicitins are associated, either directly or indirectly, with the infection process of Phytophthora. 相似文献
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Wild boar populations up,numbers of hunters down? A review of trends and implications for Europe 
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下载免费PDF全文 Giovanna Massei Jonas Kindberg Alain Licoppe Dragan Gačić Nikica Šprem Jiří Kamler Eric Baubet Ulf Hohmann Andrea Monaco Janis Ozoliņš Sandra Cellina Tomasz Podgórski Carlos Fonseca Nickolay Markov Boštjan Pokorny Carme Rosell András Náhlik 《Pest management science》2015,71(4):492-500
Across Europe, wild boar numbers increased in the 1960s–1970s but stabilised in the 1980s; recent evidence suggests that the numbers and impact of wild boar has grown steadily since the 1980s. As hunting is the main cause of mortality for this species, we reviewed wild boar hunting bags and hunter population trends in 18 European countries from 1982 to 2012. Hunting statistics and numbers of hunters were used as indicators of animal numbers and hunting pressure. The results confirmed that wild boar increased consistently throughout Europe, while the number of hunters remained relatively stable or declined in most countries. We conclude that recreational hunting is insufficient to limit wild boar population growth and that the relative impact of hunting on wild boar mortality had decreased. Other factors, such as mild winters, reforestation, intensification of crop production, supplementary feeding and compensatory population responses of wild boar to hunting pressure might also explain population growth. As populations continue to grow, more human–wild boar conflicts are expected unless this trend is reversed. New interdisciplinary approaches are urgently required to mitigate human–wild boar conflicts, which are otherwise destined to grow further. © 2014 Crown copyright. Pest Management Science © 2014 Society of Chemical Industry 相似文献
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Charles Adarkwah Daniel Obeng-Ofori Cornel Adler Carmen Büttner Christoph Reichmuth Matthias Schöller 《Phytoparasitica》2011,39(3):223-233
The compatibility and protectant potential of Calneem® oil derived from the neem tree Azadirachta indica and two parasitoids, Habrobracon hebetor and Venturia canescens, for the control of the rice moth Corcyra cephalonica (Stainton) (Lepidoptera: Pyralidae) and the tropical warehouse moth Cadra cautella Walker (Lepidoptera: Pyralidae) in stored rice and wheat, were evaluated in the laboratory. Calneem® oil (= neem oil) is a biopesticide produced, registered and marketed in Ghana by AQUA AGRIC Community Projects (AACP/Caldor Ghana Ltd., Tema). It contains 0.3% azadirachtin as its major active ingredient. The oil was emulsified with water using 0.07% soap. Fourth instar moth larvae were held in grain treated with neem oil only, grain treated with one of the parasitoids only, grain treated with a combination of neem and one of the parasitoids, and a control with untreated grain. Neem oil was applied at concentrations from 5,000 to 30,000 ppm. All samples were kept in growth cabinets maintained at 25°C and 65–70% r.h. Adult emergence was recorded after 4 weeks. Parasitoid or neem treatments alone reduced the emergence of C. cephalonica and C. cautella. In general, parasitoid releases were as effective as a combination of neem oil and parasitoids. At the lowest dose, 5,000 ppm, the combination of neem and parasitoid was more effective than the neem alone. The number of adults of H. hebetor and V. canescens that emerged in rice containing either parasitoids alone or in combination with neem oil was similar. This indicates minimal or no adverse effect of neem oil on the two parasitoids. It is thus possible to incorporate neem oil in a well-designed pest management program with parasitoids. 相似文献
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Basil N Ziogas Dimitra Nikou Anastasios N Markoglou Anastasios A Malandrakis John Vontas 《European journal of plant pathology / European Foundation for Plant Pathology》2009,125(1):97-107
The molecular basis of resistance to benzimidazole fungicides with laboratory and field mutant isolates of Botrytis cinerea was investigated. After chemical mutagenesis with N-methyl-N-nitrosogouanidine (NMNG) two different benzimidazole-resistant phenotypes were isolated on media containing carbendazim or
a mixture of carbendazim and diethofencarb. The mutant isolates from the fungicide-mixture-containing medium were moderately
resistant to carbendazim with wild-type tolerance to diethofencarb while mutant isolates from carbendazim-containing medium
were highly resistant to carbendazim but sensitive to diethofencarb. The studied field isolates were highly resistant to benzimidazoles
and sensitive to diethofencarb. Study of fitness characteristics of benzimidazole highly-resistant isolates showed that the
resistance mutation(s) had no apparent effect on fitness-determining parameters. Contrary to this, the moderately benzimidazole-resistant
strains, with no increased diethofencarb sensitivity, had a significant reduction in certain ecological fitness-determining
characteristics. Analysis of the sequence of the β-tubulin gene revealed two amino acid replacements in the highly benzimidazole-resistant mutants compared to that of the wild-type
parent strain. One was the glutamic acid (GAG) to alanine (GCG) change at position 198 (E198A), identified in both laboratory
and field highly benzimidazole-resistant isolates, a mutation previously implicated in benzimidazole resistance. The second
was a novel benzimidazole resistance mutation of glutamic acid (GAG) to glycine (GGG) substitution at the same position 198
(E198G), identified in a highly benzimidazole-resistant laboratory mutant strain. Molecular analysis of the moderately benzimidazole-resistant
strains revealed no mutations at the β-tubulin gene. A novel diagnostic PCR-RFLP assay utilising a BsaI restriction site present in the benzimidazole-sensitive (E198) but absent in both resistant genotypes (E198G and E198A)
was developed for the detection of both amino acid replacements at the β-tubulin gene. 相似文献