Genes for resistance to powdery mildew in European barley cultivars registered in the Czech Republic from 2011 to 2015

2017 ◽  
Vol 136 (3) ◽  
pp. 351-356 ◽  
Author(s):  
Antonín Dreiseitl
2010 ◽  
Vol 40 (No. 4) ◽  
pp. 135-140 ◽  
Author(s):  
A. Dreiseitl

The virulence frequencies to powdery mildew resistance genes possessed by winter barley cultivars registered and newly tested in the Czech Republic were studied in 2000, 2002 and 2004. Random samples of the populations originating from winter and spring barley fields were obtained from the air by a mobile version of a jet spore sampler mounted on a car roof. Conidia were sampled by driving across the Czech Republic. Fourteen differentials, carrying 18 out of 20 currently identified resistance genes present in winter barley cultivars, were used. High virulence frequencies (85–100%) to most resistance genes were found. Lower virulence frequencies (14.1–40.1%) were found to only three resistance genes that have not been described yet; their preliminary designations are Ml(Va), Ml(Dt) and Ml(Ca). The importance of resistance of winter barley cultivars is discussed with respect to limiting the speed with which the pathogen adapts to genetic resistances possessed by commercial cultivars of both winter and spring barley, and to the necessity of lowering the costs for powdery mildew control in barley.


2012 ◽  
Vol 47 (No. 2) ◽  
pp. 43-51 ◽  
Author(s):  
A. Dreiseitl

Virulences to powdery mildew resistances in barley cultivars mostly carrying unknown resistances were determined in 2009 and 2010. Random spore samples of the airborne pathogen populations originating from winter and spring barley fields were obtained by means of a mobile version of a jet spore sampler by travelling across theCzech Republic. In total 301 isolates were studied, 55 differentials carrying mostly unknown resistances were used and 80 pathotypes were found, of which 26 representing 73.1% of isolates were detected in both years. Virulence frequencies showed a wide range from 0% to 100%. Complexity of the 2010 population slightly increased, mostly due to increasing frequencies of virulence to new resistances, whereas the complexity of virulences to resistances in most other differentials decreased. Pathotype 00027 was the most abundant (10.0%). Diversity of the 2010 population  considerably increased due to changes in virulence frequencies.


2011 ◽  
Vol 47 (No. 2) ◽  
pp. 64-68 ◽  
Author(s):  
A. Dreiseitl

In the last two decades, resistance to the powdery mildew pathogen has been investigated in a large number of barleys in the Czech Republic. Several tens of winter barley cultivars were identified with a resistance based on an unknown gene or unknown combinations of resistance genes. In this paper tests on 20 of these cultivars are presented. Thirty-two reference isolates of Blumeria graminis f.sp. hordei were used. All the 20 cultivars shared a particular, previously unknown resistance. Landi was the first cultivar registered with this resistance and it is recommended that this resistance be designated Ln. Isolates virulent to Ln were already found randomly in old European, and also in non-European pathogen populations, where cultivars possessing the resistance Ln were never grown. On the other hand, the resistance Ln has been highly effective even 13 years after Landi registration.


2009 ◽  
Vol 44 (No. 4) ◽  
pp. 160-166 ◽  
Author(s):  
A. Dreiseitl

Virulence frequencies to powdery mildew resistances in winter barley cultivars mostly registered in the Czech Republic were studied in 2007 and 2008. Random samples of the air populations originating from winter and spring barley fields were obtained by means of a mobile version of a jet spore sampler. Conidia were sampled by driving across the Czech Republic. In total 349 isolates were studied and 17 differentials were used. The virulence frequencies to specific resistances of given cultivars showed wide range from 0% to 100%. Nine differentials were used to distinguish 134 pathotypes, of which 32 representing 63.9% of isolates were detected in both years. Pathotype 773, which broke down the resistance of eight differentials, was the most abundant. In 2008, lower virulence frequencies to all differentials, and thus lower population complexity, were determined, which may be caused by different regional origins of the isolates examined. Importance of the study of the given pathogen population is discussed in terms of successful breeding of resistant barley cultivars.


2017 ◽  
Vol 38 (SI 2 - 6th Conf EFPP 2002) ◽  
pp. 583-587
Author(s):  
M. Vaverka ◽  
S. Vaverka

In the course of 1993–2001 extensive field trials were carried out to evaluate the resistance (susceptibility) level of 34 gooseberry cultivars to the American gooseberry powdery mildew Sphaerotheca mors uvae Schwein. Cultivars originated from the Czech Republic and from other European countries. Each tested cultivar had 7 trees (5–10 years old). Beside the resistance (susceptibility) evaluation, biological efficacy of 9 fungicides using EPPO methods has been checked at the same number of cultivars and at the same number of gooseberry trees. Highly significant differences of resistance or susceptibility were observed among gooseberry varieties. Analogical results (differences in biological activity of fungicides) have been attained in the course of chemical treatment. 18 cultivars has been classified as low resistant, 12 cultivars as moderate resistant and 4 cultivars as high resistant. None of the tested fungicides proved perfect biological efficacy (100% healthy berries). 4 of them proved high biological effect (more than 90% healthy berries), 3 proved low biological activity (less than 75% healthy berries) and 2 proved moderate biological activity (75–90% healthy berries).


2010 ◽  
Vol 45 (Special Issue) ◽  
pp. S41-S47 ◽  
Author(s):  
A. Lebeda ◽  
B. Sedláková ◽  
E. Křístková ◽  
M. Vysoudil

Two ectoparasite powdery mildew species <i>Golovinomyces cichoracearum</i> (<i>Gc</i>) and <i>Podosphaera xanthii</i> (<i>Px</i>) occurring on cucurbits differ, besides other characteristics, by specific ecologic requirements. While <i>Px</i> is common in subtropical and tropical areas and greenhouse crops, <i>Gc</i> occurs more frequently in temperate and cooler areas under field conditions. Their presence on cucurbit field crops (<i>Cucurbita pepo</i>, <i>C. maxima</i>, <i>Cucumis sativus</i>) was monitored in the Czechoslovakia (1979–1980) and in the Czech Republic (1995–2007). Their identification was carried out by microscopic observation of the morphological characteristics of the dry conidia on 1527 leaf samples. Data on air temperature in 1979–2007 were provided by the Czech Hydrometeorological Institute. In 1979–1980 <i>Gc</i> was identified in 86.0% of samples, <i>Px</i> in 14.0% samples, there was no mixed infection; prevalence of <i>Px</i> was recorded in South Slovakia and South Moravia, and on crops under cover. Since 1995 species <i>Px</i> was recorded each year on field crops in different locations of Bohemia and Moravia, usually in mixed infection with <i>Gc</i>. The average year temperature of 8.1°C for period 1992–2007 was higher than corresponding value of 7.4°C in 1979–1983. Similarly, average temperature in vegetation season of 16.2°C in 1992–2007 was higher than corresponding value of 15.7°C in 1979–1983. The higher air temperature can positively influence spreading of <i>Px</i> in the Czech Republic. Climate variability and effect of their changes are discussed in relationship to the geographic distribution and geographic patterns of cucurbit powdery mildews.


2007 ◽  
Vol 56 (4) ◽  
pp. 722-722 ◽  
Author(s):  
A. Lebeda ◽  
B. Mieslerová ◽  
V. Rybka ◽  
M. Sedlářová ◽  
I. Petrželová

2008 ◽  
Vol 43 (No. 3) ◽  
pp. 77-85 ◽  
Author(s):  
A. Dreiseitl

Results of scoring the reaction to powdery mildew of 240 winter barley varieties that were gradually included in 392 Czech Official Trials conducted at 21 locations were analysed. The reaction of the varieties was determined on the basis of the level of infection by the disease. Therefore, the data can also be used to assess the disease severity in years and at locations. Several characteristics indicative of disease severity were considered, including the disease severity coefficient (= average infection of susceptible varieties in trials with a high disease severity/the proportion of such trials). The value of the coefficient is inversely proportional to disease severity. The highest powdery mildew severity was found in 1976, and the years 1988, 1990 and 2003 were characterised by high infection of the examined varieties. In contrast, the disease was practically absent in 1979 and 1982, and its severity was also low in 1978, 1981, 1985, 1991 and 1998. Very low disease severity was found for the period 1977–1982 when insufficient disease severity was found on average in 78% of the trials and high disease severity in only 6% of the trials. The highest disease severity was found at locations Trutnov, Horažďovice and Chrastava. The analysis of data from a large number of field trials conducted at various locations for a period of 30 years confirmed that powdery mildew is an important disease of winter barley in the Czech Republic. Known genetic sources of resistance and current methods, such as marker assisted selection, enable breeders to solve this problem.


Sign in / Sign up

Export Citation Format

Share Document