Resistance and virulence in the Avena: Puccinia coronata host–parasite system in Kenya and Ethiopia

1973 ◽  
Vol 51 (4) ◽  
pp. 711-714 ◽  
Author(s):  
J. W. Martens ◽  
R. I. H. McKenzie

Crown rust of oats is widespread on wild and cultivated oats in Kenya and Ethiopia. The six oat species in the area have very little resistance to crown rust, which has a wide virulence range, much wider than required for local survival. Thirteen physiologic races were identified using 10 single resistance Pc gene line cultivars. Kenya and Ethiopia appear to have distinct pathogen populations with only a few races in common.

1967 ◽  
Vol 45 (9) ◽  
pp. 1693-1701 ◽  
Author(s):  
George Fleischmann

Isolates of Puccinia coronata f.sp. avenae collected during a 15-year period were tested for virulence on the crown rust differential oat varieties. The proportion of cultures virulent on Landhafer increased relative to others during this period, and was related to the release in the United States of commercial varieties that contained this type of resistance. These varieties served to reduce the proportion of races avirulent on Landhafer in the crown rust population that reached Canada.The occurrence and subsequent increase in frequency of isolates virulent on Victoria was correlated with the release of the oat varieties Rodney and Garry which possess part of the crown rust resistance of Victoria. The increased proportion of cultures that attacked Ukraine also paralleled the release of these two commercial varieties. This suggests that Ukraine either contains the Victoria Pc-11 gene for crown rust resistance that was transferred to Rodney and Garry, or that it contains another gene in common with these varieties.Races of crown rust that are differentially virulent on the varieties Landhafer and Santa Fe have recently been found in Canada. One culture was virulent on the variety Bondvic but not on Trispernia. No increase in race 264 of crown rust, which attacks all the differential sources of resistance except Saia, has been observed since it was first identified in Canada in 1957.Presentation of the virulence of crown rust isolates for individual types of resistance was found to express the results of race surveys in terms which were more meaningful to the oat breeding program. This form of analysis also produced valuable information on the possible relationships of genes for resistance in different oat varieties not readily obtainable from conventional information on the occurrence and distribution of physiologic races of crown rust.


1944 ◽  
Vol 22c (6) ◽  
pp. 287-289 ◽  
Author(s):  
B. Peturson

The reactions of five varieties of oats in the seedling and adult plant stages to seven physiologic races of crown rust, Puccinia coronata Corda var. Avenae Erikss. & Henn. were determined.All five varieties were completely susceptible in the seedling stage to all the races. Two varieties, Erban and Ajax, were resistant in the adult plant stage to some of the races and susceptible or moderately susceptible to others. Two other varieties, R.L. No. 1370 and R.L. No. 1510 were resistant in the adult plant stage to all the races used in this test, and apparently possess a generalized type of adult plant resistance to crown rust.


1963 ◽  
Vol 41 (4) ◽  
pp. 481-487 ◽  
Author(s):  
G. Fleischmann ◽  
D. J. Samborski ◽  
B. Peturson

From 1952 to 1956 the races of crown rust, Puccinia coronata Corda f. sp. avenae Erikss., that predominated in Eastern Canada were 201, 202, 203, 209, 239, and 240. Races 201, 202, and 204 occurred most frequently in Western Canada. These races cannot attack the differential host variety Victoria, from which the currently grown commercial varieties Rodney and Garry derive their resistance. Garry and Rodney became widely grown in Canada by 1957, and since then races 216 and 274, which can attack Victoria, have become prominent, especially in Western Canada.More races are found in Eastern Canada than in the west, and there is less tendency for a few races to predominate in the east. These differences may be explained by the relatively frequent occurrence of the alternate host, Rhamnus cathartica L., in important oat-growing regions of Eastern Canada, and by the cultivation of large acreages of a few varieties with similar resistance in the west. The most important factor affecting the distribution and frequency of occurrence of races is the variety grown.


1971 ◽  
Vol 49 (8) ◽  
pp. 1433-1437 ◽  
Author(s):  
George Fleischmann ◽  
R. J. Baker

A review of the physiologic races of oat crown rust, Puccinia coronata f. sp. avenae, isolated in surveys since 1967 indicated a continuing trend toward increased virulence on the standard differential varieties of oats, Avena sativa. Because of this trend and because the inheritance and interrelationships of resistances in the standard differential set are not completely known, a new set of oat crown rust differentials has been introduced. The new set comprises 10 near-isogenic lines of the common oat variety 'Pendek,' into which single resistance genes from Avena sterilis had been transferred. A system of race nomenclature which reflects the pattern of virulence on the new set is proposed.


Plant Disease ◽  
2005 ◽  
Vol 89 (8) ◽  
pp. 802-808 ◽  
Author(s):  
K. J. Leonard ◽  
J. A. Martinelli

Race-specific resistance to crown rust, the most important disease of oat (Avena sativa) in Bra-zil, often fails within a few years of use in Brazilian cultivars. Virulence of 144 isolates of Puccinia coronata from cultivated oat in Brazil in 1997 to 1999 and 36 isolates from Uruguay in 1994-95 and 1998 was tested on a set of 27 oat crown rust differentials lines, each with a different Pc gene for race-specific resistance. Frequencies of virulence and mean virulence complexity were compared among these five collections from Brazil and Uruguay as well as with mean virulence complexity for a collection of 17 isolates from cultivated oat in western Siberia in Russia. Virulence-avirulence for each of the 27 Pc genes was polymorphic in both Brazil and Uruguay. Virulence frequencies were similar for collections from Brazil in 1998 and 1999 and for the collection from Uruguay from 1998, but there were large differences between the 1997 collection and the 1998 and 1999 collections from Brazil. Mean virulence complexity in both Brazil and Uruguay was greater than reported in the United States and much greater than in the Russian collection of P. coronata. A large number of races of P. coronata were found, with no more than five isolates of any race found in a single year in Brazil or Uruguay. The high virulence complexity and great diversity of virulence polymorphisms in Brazil and Uruguay make it unlikely that race-specific resistance can be effective there even though the South American populations of P. coronata are apparently entirely asexual.


Plant Disease ◽  
2018 ◽  
Vol 102 (5) ◽  
pp. 955-963
Author(s):  
Brijesh B. Karakkat ◽  
Vonte L. Jackson ◽  
Paul L. Koch

Crown rust (caused by Puccinia coronata) and stem rust (caused by P. graminis) are two common and destructive diseases of turfgrass in the United States. Crown rust has been associated with perennial ryegrass and stem rust with Kentucky bluegrass when identified based solely on fungal morphology. However, recent studies using molecular identification methods have indicated the host–pathogen relationship of rusts on turf to be more complex. Our primary objective was to quickly and accurately identify P. coronata and P. graminis in symptomatic turfgrass leaves over 3 years on turfgrass samples from across the Midwestern United States. Between 2013 and 2015, 413 samples of symptomatic cool-season turfgrass from Wisconsin and surrounding states were screened using real-time polymerase chain reaction. Of these samples, 396 were Kentucky bluegrass and 17% of them contained P. coronata, 69% contained P. graminis, and 13% contained both P. coronata and P. graminis. In addition, both year and location effects were observed on the distribution of Puccinia spp. collected annually from two locations in southern Wisconsin. This research supports previous conclusions that have identified variability among P. graminis and P. coronata host relationships on turfgrass, and further demonstrates that rust fungal populations on Kentucky bluegrass may not be consistent between locations in the same year or over multiple years at the same location. The increasing evidence of variation in the turfgrass rust populations will likely affect future rust management and turfgrass breeding efforts.


Author(s):  
H.S. Easton ◽  
B.M. Cooper ◽  
T.J. Frasers ◽  
K.H. Widdup

Crown rust infection of 11 perennial ryegrass cultivars vaned significantly and consistently over 6 sites. 'Grasslands Ariki,' the new cultivar 'Yatsyn' and Grasslands selections G26 and G33 were less infected than 'Grasslands Nui', 'Ellett' or 'Grasslands Ruanui'. 'Droughtmaster' and 'Marathon' proved more susceptible than most. Keywords: Crown rust, Puccinia coronata. perenmal ryegrass


Author(s):  
Peter Dracatos ◽  
Jeremy Dumsday ◽  
Alan Stewart ◽  
Mark Dobrowolski ◽  
Noel Cogan ◽  
...  

Author(s):  
Peter Dracatos ◽  
Jeremy Dumsday ◽  
Alan Stewart ◽  
Mark Dobrowolski ◽  
Noel Cogan ◽  
...  

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