Characterization of the Molecular Mechanisms of Resistance against DMI Fungicides in Cercospora beticola Populations from the Czech Republic

Cercospora leaf spot (CLS), caused by the fungal pathogen Cercospora beticola, is the most important foliar pathogen of sugar beet worldwide. Extensive reliance on fungicides to manage CLS has resulted in the evolution of fungicide resistance in C. beticola worldwide, including populations in the Czech Republic. One important class of fungicides used to manage CLS is the sterol demethylation inhibitors (DMI). The aim of our study was to assess DMI resistance in C. beticola from the Czech Republic and elucidate the molecular basis of DMI resistance in this population. A total of 50 isolates were collected in 2018 and 2019 from the major sugar beet growing regions of the Czech Republic and assessed for in vitro sensitivity to the DMI fungicides propiconazole, prochloraz, and epoxiconazole. These analyses identified three strains that exhibited 50% effective concentration (EC50) values > 1.0 μg mL–1 against respective fungicides, which were therefore considered resistant. In contrast, strains that exhibited lowest EC50 values were considered sensitive. To explore the molecular basis of resistance in these three strains, the cytochrome P450-dependent sterol 14α-demethylase (Cyp51) gene was sequenced. Sequence analysis identified a Y464S mutation in all three resistant strains. To assess whether Cyp51 gene expression may play a role in DMI resistance, selected strains were grown in vitro with and without fungicide treatment. These analyses indicated that Cyp51 gene expression was significantly induced after fungicide treatment. Thus, we conclude that Y464S point mutation along with induced Cyp51 gene overexpression is likely responsible for resistance against DMI fungicides in C. beticola from the Czech Republic.

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Efficacy of Variable Tetraconazole Rates Against Cercospora beticola Isolates with Differing In Vitro Sensitivities to DMI Fungicides

Plant Disease ◽

10.1094/pdis-03-12-0255-re ◽

2012 ◽

Vol 96 (12) ◽

pp. 1749-1756 ◽

Cited By ~ 17

Author(s):

Melvin D. Bolton ◽

Viviana Rivera-Varas ◽

Luis E. del Río Mendoza ◽

Mohamed F. R. Khan ◽

Gary A. Secor

Keyword(s):

Sugar Beet ◽

Disease Severity ◽

Cercospora Beticola ◽

In Planta ◽

Sensitivity Testing ◽

In Vitro Sensitivity ◽

Wide Range ◽

Fungicide Efficacy ◽

Dmi Fungicides

Cercospora leaf spot (CLS) of sugar beet is caused by the fungus Cercospora beticola. CLS management practices include the application of the sterol demethylation inhibitor (DMI) fungicides tetraconazole, difenoconazole, and prothioconazole. Evaluating resistance to DMIs is a major focus for CLS fungicide resistance management. Isolates were collected in 1997 and 1998 (baseline sensitivity to tetraconazole, prothioconazole, or difenoconazole) and 2007 through 2010 from the major sugar-beet-growing regions of Minnesota and North Dakota and assessed for in vitro sensitivity to two or three DMI fungicides. Most (47%) isolates collected in 1997–98 exhibited 50% effective concentration (EC50) values for tetraconazole of <0.01 μg ml–1, whereas no isolates could be found in this EC50 range in 2010. Since 2007, annual median and mean tetraconazole EC50 values have generally been increasing, and the frequency of isolates with EC50 values >0.11 μg ml–1 increased from 2008 to 2010. In contrast, the frequency of isolates with EC50 values for prothioconazole of >1.0 μg ml–1 has been decreasing since 2007. Annual median difenoconazole EC50 values appears to be stable, although annual mean EC50 values generally have been increasing for this fungicide. Although EC50 values are important for gauging fungicide sensitivity trends, a rigorous comparison of the relationship between in vitro EC50 values and loss of fungicide efficacy in planta has not been conducted for C. beticola. To explore this, 12 isolates exhibiting a wide range of tetraconazole EC50 values were inoculated to sugar beet but no tetraconazole was applied. No relationship was found between isolate EC50 value and disease severity. To assess whether EC50 values are related to fungicide efficacy in planta, sugar beet plants were sprayed with various dilutions of Eminent, the commercial formulation of tetraconazole, and subsequently inoculated with isolates that exhibited very low, medium, or high tetraconazole EC50 values. The high EC50 isolate caused significantly more disease than isolates with medium or very low EC50 values at the field application rate and most reduced rates. Because in vitro sensitivity testing is typically carried out with the active ingredient of the commercial fungicide, we investigated whether loss of disease control was the same for tetraconazole as for the commercial product Eminent. The high EC50 isolate caused more disease on plants treated with tetraconazole than Eminent but disease severity was not different between plants inoculated with the very low EC50 isolate.

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Resistance behaviour of Septoria tritici to some fungicides in the territory of the Czech Republic

Acta Agrobotanica ◽

10.5586/aa.2005.012 ◽

2012 ◽

Vol 58 (1) ◽

pp. 79-84 ◽

Cited By ~ 2

Author(s):

Ludvik Tvaružek ◽

P. Horáková ◽

L. Ji

Keyword(s):

Czech Republic ◽

Septoria Tritici ◽

Resistance Development ◽

The Czech Republic ◽

Colony Diameter ◽

Dmi Fungicides ◽

The Mean ◽

Different Parts ◽

Pathogen Strains

Reduction of colony diameter using two DMI-fungicides and one strobilurine fungicide was evaluated in the Septoria tritici population. In an in vitro assay, 57 strains of S. tritici originating from different parts of the Czech Republic were grown on agar plates containing different concentrations of fungicides. The mean EC50 values of strains were analysed for flusilazole (Capitain), metconazole (Caramba) and one strobilurine fungicide: azoxystrobin (Amistar). ED 50 values for metconazole were low. There were highly significant correlation in reaction of pathogen strains to metconazole and flusilazole. Some isolates showed significant higher level of resistance to azoxystrobin. The data will be used in a continuing survey of resistance development in the S. tritici population originating from the territory of the Czech Republic.

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The assessment of the economic risks level of sugar beet growing for the farm economy

Agricultural Economics (Zemědělská ekonomika) ◽

10.17221/111/2010-agricecon ◽

2012 ◽

Vol 58 (No. 1) ◽

pp. 41-48 ◽

Cited By ~ 1

Author(s):

J. Pulkrábek ◽

M. Kavka ◽

V. Rataj ◽

J. Humpál ◽

L. Nozdrovický ◽

...

Keyword(s):

Czech Republic ◽

Sugar Beet ◽

Positive Impact ◽

Fixed Costs ◽

Acceptable Risk ◽

Sugar Beets ◽

The Czech Republic ◽

Risk Rate ◽

Break Even Point ◽

Economic Risks

The risk rate of sugar beet growing was analyzed by using the algorithm for modelling and generating the random numbers based on the conditions determined in advance and the statistical distribution of sugar beets yield, the total costs, earnings and gross profit. On the bases of results of the analysis of economic risks of sugar beet production in years 1995–2009, it follows that the sugar beet growing in all regions is highly risky in the Czech Republic. The subsidy SAPS and TOP-UP per 1 hectare of sugar beet have a positive impact on its economics though not sufficient enough. In practice, it means that it is highly probable that the break-even point will not be achieved and thereby it is highly probable that the fixed costs are not covered and the update of machines is significantly limited. This happens mainly in the marginal regions. If the agricultural companies count on the separate sugar payment, the sugar beet growing is in all regions of the Czech Republic with acceptable risk.  

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Competitiveness in the production of selected crops from the perspective of variable costs

Agricultural Economics (Zemědělská ekonomika) ◽

10.17221/5242-agricecon ◽

2012 ◽

Vol 50 (No. 11) ◽

pp. 514-523

Author(s):

D. Matošková

Keyword(s):

Czech Republic ◽

Comparative Analysis ◽

Sugar Beet ◽

Profit Margin ◽

Basic Variable ◽

The Czech Republic ◽

Average Figure

This article deals with the issue of Slovakia’s competitiveness vis-ŕ-vis the Czech Republic, Poland, Hungary, Germany, Austria and France in terms of basic variable costs invested into seeds (planting stocks), fertilisers and chemical protective in the period from 2001 to 2003. In addition to these costs, the article also compares total revenues, profit, effect of inputs into production and the variable costs profit margin. This comparative analysis uses data published for 2002. While the data for years 2001 and 2003 for Slovakia and the Czech Republic are actual, those for other countries have been simulated. The basic variable costs per tonne of the produced crop (average figure for 2001 and 2003) in Slovakia are lower, i.e. it is competitive in the production of cereals, sunflower and sugar beet vis-ŕ-vis the observed EU-15 countries, barley, sunflower and sugar beet vis-ŕ-vis the Czech Republic, wheat and barley vis-ŕ-vis Poland and barley vis-ŕ-vis Hungary.

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Influence of policy measures on the competitiveness of the sugar industry in the Czech Republic

Agricultural Economics (Zemědělská ekonomika) ◽

10.17221/5385-agricecon ◽

2012 ◽

Vol 49 (No. 6) ◽

pp. 266-274 ◽

Cited By ~ 1

Author(s):

M. Bavorová

Keyword(s):

Czech Republic ◽

Sugar Beet ◽

Agricultural Policy ◽

Food Production ◽

Sugar Industry ◽

The Czech Republic ◽

National Market ◽

Policy Measures

The sugar industry in the Czech Republic is one of the branches of food production that since the end of nineties has been strongly protected by agricultural policy. Here, we will deal with the question how the Czech agricultural policy affected the competitiveness of the sugar industry during transformation. From the analysis, it can be derived that not only agricultural measures but also organisational changes inside the enterprises, as well as modernisation and increasing capacity of plants  that all took place before the enforced political aid, supported the stabilisation of sugar beet farming and the sugar industry in the Czech Republic and its competitiveness in the national market.

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Exploring the hidden potential of sugar beet industry brownfields (case study of the Czech Republic)

Transportation Research Part D Transport and Environment ◽

10.1016/j.trd.2016.04.006 ◽

2016 ◽

Vol 46 ◽

pp. 284-297 ◽

Cited By ~ 8

Author(s):

Tomáš Krejčí ◽

Ivo Dostál ◽

Marek Havlíček ◽

Stanislav Martinát

Keyword(s):

Czech Republic ◽

Sugar Beet ◽

The Czech Republic

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Genome-wide differential gene expression in children exposed to air pollution in the Czech Republic

Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis ◽

10.1016/j.mrfmmm.2006.05.032 ◽

2006 ◽

Vol 600 (1-2) ◽

pp. 12-22 ◽

Cited By ~ 35

Author(s):

D.M. van Leeuwen ◽

M.H.M. van Herwijnen ◽

M. Pedersen ◽

L.E. Knudsen ◽

M. Kirsch-Volders ◽

...

Keyword(s):

Gene Expression ◽

Air Pollution ◽

Czech Republic ◽

Differential Gene Expression ◽

The Czech Republic ◽

Genome Wide ◽

Differential Gene

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Protocol for efficient micropropagation of spring gentian and sand jurinea

Journal of Forest Science ◽

10.17221/60/2013-jfs ◽

2014 ◽

Vol 60 (No. 1) ◽

pp. 1-5

Author(s):

H. Cvrčková ◽

P. Máchová ◽

J. Dostál ◽

J. Malá

Keyword(s):

Czech Republic ◽

Plant Species ◽

In Vitro Propagation ◽

Casein Hydrolysate ◽

Endangered Plant ◽

Ms Medium ◽

The Czech Republic ◽

Endangered Plant Species ◽

Primary Explants

Protocols for the in vitro propagation of two endangered plant species in the Czech Republic, Gentiana verna L. and Jurinea cyanoides (L.) Rchb., were established. In G. verna, the induction of organogenesis on vegetative shoots was successful on the basal 6% agar WPM medium with 200 mg·l–1of glutamine, 200 mg·l–1 of casein hydrolysate, 30 g·l–1 of sucrose, 0.2 mg·l–1 of BAP, and 0.1 mg·l–1 of IBA. The multiplication of primary explants was achieved on 6% agar basal MS medium with the same concentrations of substances mentioned above. In J. cyanoides, the induction of organogenesis and multiplication of its vegetative shoots were successful on MS medium with the same concentration of added substances used in G. verna. On the basal MS medium of 1/3 concentration with 3 mg·l–1 of IBA 70–75% rooting efficiency of G. verna microcuttings and 40% rooting efficiency of J. cyanoides microcuttings were reached. The mortality during acclimatization did not exceed 20% for G. verna and 25% for J. cyanoides.

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Influence of selected fungicides registered in the Czech Republic for winter oilseed rape on in vitro Sclerotinia sclerotiorum mycelial growth

Plant Protection Science ◽

10.17221/137/2016-pps ◽

2018 ◽

Vol 54 (No. 2) ◽

pp. 101-110 ◽

Cited By ~ 1

Author(s):

Poslušná Jana ◽

Plachká Eva ◽

Mazáková Jana

Keyword(s):

Czech Republic ◽

Oilseed Rape ◽

Sclerotinia Sclerotiorum ◽

Mycelial Growth ◽

Winter Oilseed Rape ◽

Baseline Sensitivity ◽

The Czech Republic ◽

Dose Rates ◽

The Mean

The baseline sensitivity of 55 isolates of Sclerotinia sclerotiorum, collected from oilseed rape in 6 regions of the Czech Republic, to selected fungicides was determined during the period 2013–2015. One single-component fungicide – Horizon (tebuconazole), and four multicomponent fungicides – Pictor (boscalid, dimoxystrobin), Efilor (boscalid, metconazole), Prosaro 250 EC (prothioconazole, tebuconazole), and Propulse (fluopyram, prothioconazole), were chosen as these are commonly used locally. The effect of each fungicide on the in vitro pathogen radial mycelial growth and EC50 values for the respective fungicides were determined. The following MIC values were estimated; for the fungicides Horizon 250 EW, Efilor, and Propulse the mean MIC values ranged between 0.125 and 0.250 µl/ml, for Prosaro 250 EC ranged between 0.0625 and 0.125 µl/ml, and for Pictor ranged from 0.00781 to 0.01562 µl/ml. No strains of S. sclerotiorum resistant to the tested fungicides were detected and the growth of all isolates was fully inhibited at concentrations corresponding to their registered dose rates. The highest fungicidal efficacy on the collected S. sclerotiorum isolates was recorded for Pictor, followed by Prosaro 250 with an EC50 value 0.05856 µl/ml and then the remaining fungicides Propulse, Efilor, and Horizon 250 EW (EC50 values 0.07277, 0.07221, and 0.08519 µl/ml, respectively).

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Preliminary results from a plantation of semi-arid hybrid of Paulownia Clone in vitro 112® under conditions of the Czech Republic from the first two years

BALTIC FORESTRY ◽

10.46490/bf477 ◽

2020 ◽

Vol 27 (1) ◽

Author(s):

Jiří Kadlec ◽

Kateřina Novosadová ◽

Radek Pokorný

Keyword(s):

Czech Republic ◽

Frost Damage ◽

Continuous Treatment ◽

Woven Fabric ◽

The Czech Republic ◽

Plain Area ◽

Growing Conditions ◽

Private Owner ◽

Semi Arid

A private owner established a plantation of a semi-arid hybrid of Paulownia Clone in vitro 112® near the village of Střelice u Brna in 2016. We split the plantation according to terrain micro-relief (into three expositions: South slope, Plain area and North slope) and according to the applied biotechnology of planting (into two parts: each with planting into 20 and 30 cm holes in diameter). We tested different winter protection techniques for above and belowground plant organs. The results suggest that plants inside the 30 cm holes survive and grow better than those inside the 20 cm ones, regardless of terrain micro-relief. On the other hand, plants inside the 20 cm holes survive and grow better on flat areas compared to the others. The most effective protection of the root system against frost during the wintertime seems to be simple soil covering. We have also recognized that bandage of non-woven fabric is the best protection for the above-ground parts of the plants. However, growing conditions in the Czech Republic (CR) are different to those in semi-arid climate for which researchers bred the Paulownia Clone in vitro 112®. It is possible to achieve well-growing and surviving Paulownia plants under growing conditions of the CR when appropriate biotechnology and continuous treatment are applied. Keywords: Paulownia Clone in vitro 112®, plantation, exposition, mortality, growth, protection against frost damage

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