Diagnosis Tsn1 gene of Pyrenophora tritici-repentis in wheat varieties and their resistance to races of the pathogen

2018 ◽  
Vol 1 (72) ◽  
pp. 206-210
Author(s):  
Oksana Kremneva ◽  
◽  
Galina Volkova ◽  
Keyword(s):  
Wheat Varieties ◽  
Pyrenophora Tritici Repentis

scholarly journals Isolate Virulence and Cultivar Response in the Winter Wheat: Pyrenophora tritici-repentis (Tan Spot) Pathosystem in Oklahoma

2021 ◽  
Vol 37 (4) ◽  
pp. 339-346
Author(s):  
Kazi A. Kader ◽  
Robert M. Hunger ◽  
Mark E. Payton
Keyword(s):  
Cluster Analysis ◽  
Leaf Area ◽  
Tan Spot ◽  
Wheat Cultivars ◽  
Cultivar Resistance ◽  
Wheat Varieties ◽  
Pyrenophora Tritici Repentis ◽  
Greenhouse Study ◽  
No Till ◽  
Increased Susceptibility

Prevalence of tan spot of wheat caused by the fungus Pyrenophora tritici-repentis has become more prevalent in Oklahoma as no-till cultivation in wheat has increased. Hence, developing wheat varieties resistant to tan spot has been emphasized, and selecting pathogen isolates to screen for resistance to this disease is critical. Twelve isolates of P. tritici-repentis were used to inoculate 11 wheat cultivars in a greenhouse study in splitplot experiments. Virulence of isolates and cultivar resistance were measured in percent leaf area infection for all possible isolate x cultivar interactions. Isolates differed significantly (P < 0.01) in virulence on wheat cultivars, and cultivars differed significantly in disease reaction to isolates. Increased virulence of isolates detected increased variability in cultivar response (percent leaf area infection) (r = 0.56, P < 0.05) while increased susceptibility in cultivars detected increased variance in virulence of the isolates (r = 0.76, P < 0.01). A significant isolate × cultivar interaction indicated specificity between isolates and cultivars, however, cluster analysis indicated low to moderate physiological specialization. Similarity in wheat cultivars in response to pathogen isolates also was determined by cluster analysis. The use of diverse isolates of the fungus would facilitate evaluation of resistance in wheat cultivars to tan spot.

Identification of a major QTL for yellow leaf spot resistance in the wheat varieties Brookton and Cranbrook

2004 ◽  
Vol 55 (3) ◽  
pp. 315 ◽  
Author(s):  
J. Cheong ◽  
H. Wallwork ◽  
K. J. Williams
Keyword(s):  
Microsatellite Markers ◽  
Leaf Spot ◽  
Bulked Segregant Analysis ◽  
Tan Spot ◽  
Resistance Locus ◽  
Yellow Leaf ◽  
Wheat Varieties ◽  
Seedling Resistance ◽  
Pyrenophora Tritici Repentis ◽  
Chromosome 5B

Yellow leaf spot (YLS) or tan spot, caused by Pyrenophora tritici-repentis, is a major foliar disease of wheat. A bioassay was used to identify YLS seedling resistance phenotypes of Krichauff/Brookton and Cranbrook/Halberd doubled-haploid (DH) populations. Bulked-segregant analysis was used to identify amplified fragment length polymorphism (AFLP) markers linked to a YLS resistance locus in the wheat cultivar Brookton. Three AFLPs were linked to YLS resistance and also to each other. One of these AFLPs was mapped to the interval Xbcd351–Xcdo400, which has been assigned to chromosome 5BL. Microsatellite markers in this region were selected from several maps and were genotyped on the Krichauff/Brookton population. Together with the bulked segregant analysis (BSA)-derived AFLPs, the microsatellite markers explained up to 39% of the total phenotypic variation (logarithm of odds ratio, LOD ≥� 7.32), confirming the chromosome 5BL assignment of a Brookton YLS resistance locus, at or near the previously identified Pyrenophora tritici-repentis toxin-insensitivity locus tsn1. The marker–trait linkage was validated in the Cranbrook/Halberd DH population, in which the same microsatellite markers explained up to 60% of the total trait variance for YLS. The markers identified can be used for the selection of the Brookton and Cranbrook YLS seedling resistance locus on chromosome 5B.

scholarly journals Differentially expressed gene transcripts in wheat and barley leaves upon leaf spot infection

2012 ◽  
Vol 48 (No. 3) ◽  
pp. 108-119 ◽  
Author(s):  
V. Dumalasová ◽  
L. Svobodová ◽  
A. Hanzalová
Keyword(s):  
Plant Pathogen ◽  
Time Course ◽  
Expression Profiles ◽  
Wheat Variety ◽  
Differentially Expressed Gene ◽  
Crop Species ◽  
Wheat Varieties ◽  
Pyrenophora Tritici Repentis ◽  
Barley Leaves ◽  
Plant Pathogen Interaction

A cDNA library was created on the basis of transcripts that were generated during the process of infection of wheat and barley with Pyrenophora tritici-repentis or P. teres. Due to the time course of infection assays, the leaves were collected at various intervals after inoculation until 100 h after inoculation. We compared the temporal development of the two pathogens, as well as the effect of varieties of the same crop species, and differences among isolates of a single pathogen. The appressoria and vesicular structures developed more rapidly in barley varieties inoculated by P. teres than in wheat varieties inoculated by P. tritici-repentis. The lower level of susceptibility of the wheat variety Globus and the barley variety Heris to P. tritici-repentis and P.&nbsp;teres, respectively, was apparent from 12 h after infection. Information on changes in expression profiles during pathogenesis and on the clones that could be functionally assigned to the known gene sequences is presented. Out of the 360 transcript derived fragments (TDFs) produced in the barley-P. teres pathosystem in our trials, 62% were specific to the plant-pathogen interaction. In the wheat-P. tritici-repentis pathosystem 291 TDFs occurred, 63% were specific to the plant-pathogen interaction.

scholarly journals IDENTIFICATION WHEAT GENOTYPES RESISTANT TO TAN SPOT PYRENOPHORA TRITICI-REPENTIS

2020 ◽  
Vol 384 (2) ◽  
pp. 29-35
Author(s):  
A. Kokhmetova ◽  
M. Atishova
Keyword(s):  
Cultural Practices ◽  
Field Evaluation ◽  
Field Resistance ◽  
Tan Spot ◽  
Molecular Screening ◽  
Wheat Varieties ◽  
Wheat Genotypes ◽  
Wheat Germplasm ◽  
Pyrenophora Tritici Repentis ◽  
Ptr Toxa

Intensified wheat production, changes in cultural practices including shifts from conventional tillage to reduced tillage practices, and wheat monoculture involving cultivation of susceptible cultivars has resulted in development of tan spot to epidemic proportions in Kazakhstan. Pyrenophora tritici-repentis, causal agent of tan spot on wheat. In recent years, there has been increasing distribution and harmfulness of P. tritici-repentis on wheat. The aim of the study was to identify and select wheat germplasm resistant to tan spot P. tritici-repentis using molecular markers. The results of field evaluation showed resistant reaction to tan spot in 76 wheat varieties (68%). Molecular screening of wheat germplasm was carried out based on the reaction to the fungal inoculum and to host-specific toxins (HST) produced by the P. tritici-repentis. The wheat germplasm insensitive to the toxins HST Ptr ToxA and Ptr ToxB was selected. As a result of molecular screening of 111 wheat genotypes using SSR marker Xfcp623 linked to insensitivity gene to the selective toxin Ptr ToxA of tan spot, 31 carriers of effective tsn1 gene were identified, which accounted for 27,9% of the genotypes studied. Ten samples of wheat (Jubileynaya 60, TOO11/TOOOO7, F3.71/TRM/VORONA/3/OC14, NANJTNG 82149 KAUZ, ECHA/LI115, Akmola 2, Kazakh-stanskaya rannespelaya, Kazakhstanskaya 25, 428g/MK-122A and 190-Naz/GF55) are characterized with complex resistance to the races Ptr 1 and 5, as well as to 2 toxins (ToxA and ToxB) and to the Septoria nodorum blotch isolate SNB7k. 20 promising wheat lines resistant to tan spot were selected. These genotypes also showed a moderate and high level of field resistance and recommended to use in the breeding programs for resistance to tan spot.

scholarly journals Genetic polymorphism of ToxB+ Pyrenophora tritici-repentis strains

2021 ◽  
Vol 19 (2) ◽  
pp. 121-129
Author(s):  
Nina V. Mironenko ◽  
Aleksandra S. Orina ◽  
Nadezhda M. Kovalenko
Keyword(s):  
Copy Number ◽  
Low Frequency ◽  
Original Strain ◽  
Division Rate ◽  
Wheat Varieties ◽  
Additional Function ◽  
Average Copy Number ◽  
Pyrenophora Tritici Repentis ◽  
Leaf Chlorosis ◽  
Average Copy

BACKGROUND: The phytotoxin Ptr ToxB as well as Ptr ToxA is one of the pathogenic factors of Pyrenophora tritici-repentis, that cause leaf chlorosis on susceptible wheat varieties, and is encoded by ToxB gene. P. tritici-repentis strains with ToxB gene are rather rare worldwide. MATERIALS AND METHODS: The object of the study was 37 strains isolated from the leaves of wheat grown in Greece. The virulence of the strains was analyzed and the presence of effector genes as well as the average copy number of ToxB was determined. RESULTS: The race composition of P. tritici-repentis population turned out to be mainly represented by the avirulent race 4 (50% of the strains). Strains of race 1 were not found, while strains of other races were found with a low frequency in the population. All analyzed P. tritici-repentis strains had ToxB gene in the genome, while its homologues and ToxA gene were not detected. The average copy number (R) of ToxB in three P. tritici-repentis strains varied from 0.24 to 1.22. The average copy number of ToxB in the mitotic generation of P. tritici-repentis Gr8 strain, which was characterized by the lowest value of R = 0.24, varied from 0.01 to 0.74 and, on average, turned out to be 2 times higher than in the original strain Gr8. CONCLUSION: Presumably, P. tritici-repentis has a mechanism that gives ToxB+ nuclei an advantage in the division rate over ToxB nuclei. This mechanism indicates the existence of an additional function of this gene that is not associated with pathogenicity.

QUALITATIVE STABILITY OF WINTER WHEAT VARIETIES AT DIFFERENT LOCATIONS

2000 ◽  
Vol 48 (2) ◽  
pp. 191-195
Author(s):  
C. Kondora ◽  
M. Szabó ◽  
A. Máté ◽  
G. Szabó
Keyword(s):  
Quality Control ◽  
Winter Wheat ◽  
Evaluation Method ◽  
Wheat Varieties ◽  
Local Conditions ◽  
Grain Yields ◽  
Baking Quality ◽  
Small Plot ◽  
High Yielding Varieties ◽  
Winter Wheat Varieties

Owing to the significant differences in the adaptability of state-registered varieties, those which can adapt well to the local conditions should be given preference. There are several high-yielding varieties available in Hungary with excellent agronomic properties, good adaptability and satisfactory baking quality. This study was conducted to analyse the adaptability of 34 state-registered winter wheat varieties tested in the small plot trials of the National Institute for Agricultural Quality Control (NIAQC) at 5–9 locations between 1994 and 1997 based on their gluten quantity and farinographic index. For the comparison of the varieties the evaluation method of Eberhart and Russell (1966) was applied as modified by Bedő and Balla (1977). The qualitative stability and adaptability values of the varieties differ from the adaptability and stability values calculated from the grain yields. Some winter wheat varieties have good qualitative adaptability and stability, while others have special adaptability and poor qualitative stability, but the majority of the varieties do not belong to these groups.

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