An interpretation of the frequencies of host specific phenotypes of <i>Phytophthora infestans</i> in North Wales

Shattock, R. C.; Janßen, Benedikt; Whitbread, R.; Shaw, David

doi:10.1111/j.1744-7348.1977.tb01838.x

Cited by 41 publications

(19 citation statements)

References 17 publications

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“…Up to this point P. infestans populations of the A1 mating type in Europe showed little variation and isolates overcoming R1, R2 and R3 had not been identified. Importantly, it appears that selection pressure imposed upon the pathogen population by the widespread use of Pentland Dell increased the frequency of more complex isolates (Shattock et al 1977). Alongside other studies, Pentland Dell has illustrated the risks of relying on host resistance for disease control without due consideration of how the pathogen population may respond to its deployment, and has also sparked intensive searches for potentially more durable forms of resistance that focus on R genes and quantitative sources of resistance from other wild, P. infestans resistant, Solanum species (Bradshaw et al 2004a;Bradshaw and Birch 2006).…”

Section: Previous P Infestans Resistance Breedingmentioning

confidence: 99%

Progress in Mapping and Cloning Qualitative and Quantitative Resistance Against Phytophthora infestans in Potato and Its Wild Relatives

Hein¹,

Birch²,

Danan

et al. 2009

Potato Res.

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Cultivated potato is susceptible to many pests and pathogens, none of which is more of a threat to potato agriculture than the late blight disease, caused by the oomycete Phytophthora infestans (Mont.) de Bary. To date all efforts to thwart this most adaptive of pathogens have failed, and early attempts to deploy 'R genes' introgressed from the wild Mexican hexaploid Solanum demissum ended in abject failure. With the advent of facile gene mapping and cloning, allied to knowledge of plant resistance gene structure, renewed efforts are leading to mapping and isolation of new sources of late blight resistance in potato wild species, many of which are being performed under the auspices of the BIOEXPLOIT project (Sub-project 2). We document recent advances in late blight resistance gene mapping and isolation, and postulate how these genes, allied to knowledge of pathogen effectors and their recognition specificity, may greatly enhance our chances of halting the progress of late blight disease in potato crops worldwide.

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Section: Previous P Infestans Resistance Breedingmentioning

confidence: 99%

Progress in Mapping and Cloning Qualitative and Quantitative Resistance Against Phytophthora infestans in Potato and Its Wild Relatives

Hein¹,

Birch²,

Danan

et al. 2009

Potato Res.

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“…Early examples of unsuccessful use of genetic resistance were the potato cultivars Pentland Dell and Maris Peer, with resistance to late blight based on simple combinations of R genes, which were overcome as the frequency of matching virulence genes in the P. infestans population increased (Malcolmson, 1969). This increase is a direct result of the selection pressure imposed upon the pathogen population by the cultivation of these cultivars (Shattock et al, 1977) and illustrates the potential problems of relying on host resistance for disease control without proper consideration of how the pathogen population may respond to its deployment.…”

Section: Resultsmentioning

confidence: 99%

Mating type, mefenoxam sensitivity, and pathotype diversity in Phytophthora infestans isolates from tomato in Brazil

Miranda

Suassuna

Reis

2010

Pesq. agropec. bras.

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− The objective of this work was to characterize 79 Phytophthora infestans isolates collected in tomato (Solanum lycopersicum) fields, as to mating type, mefenoxam sensitivity, and pathotype composition. The isolates were sampled in 2006 and 2007 in seven Brazilian states as well as in the Distrito Federal. They were characterised as to mating type (n=79), sensitivity to fungicide mefenoxam (n=79), and virulence to three major resistance genes Ph-1, Ph-2, and Ph-3/Ph-4 (n=62). All isolates were of the mating type A1. Resistant isolates were detected in all sampled states, and its average frequency was superior to 50%. No difference was detected in pathotype diversity, neither between subpopulations collected in 2006 and 2007 nor between isolates grouped as resistant or intermediately sensitive to mefenoxam. All major resistance genes were overcome at different frequencies: 88.7%; 64.5%; 25.8%. Isolates with virulence genes able to overcome all major resistance genes were detected at low frequencies. Tomato breeding programs in Brazil must avoid the development of cultivars with resistance based exclusively on major genes.

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“…The presence of these improved cultivars is probably important for the development of new races, ultimately contributing to a high level of racial diversity in these regions. The association between commercial potato cultivars possessing R genes from Solanum demissum and complex races of P. h~festans have previously been documented (Shattock et al, 1977). The traditional seed potatoes supply system allowing unidirectional flow (high hills to hills and terai only) of seed material in Nepal may have limited the movement of new races from the terai and hills to the high hills.…”

Section: Potato Research 44 (2001)mentioning

confidence: 96%

“…Race structure data are now available for many countries (Andrivon, 1994a;Deahl et al, 1993;Dorrance et al, 1999;Dowley et al, 2000;Forbes et al, 1997;Hermansen et al, 2000;Malcolmson, 1969;O'Sullivan & Dowley, 1983;Rivera-Pefia, 1990, 1996SchOber & Turkensteen, 1992;Shattock et al, 1977;Tooley et al, 1986Tooley et al, , 1989. Besides the few early studies conducted in China (Huang et al, 1981;Li, 1988) and India Phadtare et al, 1971Phadtare et al, , 1973Phukan & Barua, 1991) and a single study conducted in Nepal (Shrestha, 1977), there is a lack of race structure data from this region.…”

Section: Introductionmentioning

confidence: 98%

Race diversity and virulence complexity ofPhytophthora infestans in Nepal

et al. 2001

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SummaryA total of 251 Phytophthora infestans isolates collected during 1999-2000 potato growing seasons from nine potato growing areas of Nepal were tested for virulence using a set of eleven potato differentials. The virulence test revealed the presence of 30 races with the most frequent being 4.11, 4 and 11. Twenty-nine percent of isolates belonged to simple races having none to one virulence factor, whereas 71% had complex virulence factors governed by 2 to 7 genes. Gleason and Shannon indices of 5.24 and 2.59, respectively, showed a moderate level of diversity in Nepalese P. infestans populations. Shannon indices comparison among regional populations revealed significant differences (t-test, P<0.001) in the diversity. The population from hills were the most diverse followed by terai and the high hill populations. The virulence complexities were minimal in Nepalese populations. The implications of these findings in association with the potato cultivation system in Nepal are discussed.

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An interpretation of the frequencies of host specific phenotypes of Phytophthora infestans in North Wales

Cited by 41 publications

References 17 publications

Progress in Mapping and Cloning Qualitative and Quantitative Resistance Against Phytophthora infestans in Potato and Its Wild Relatives

Progress in Mapping and Cloning Qualitative and Quantitative Resistance Against Phytophthora infestans in Potato and Its Wild Relatives

Mating type, mefenoxam sensitivity, and pathotype diversity in Phytophthora infestans isolates from tomato in Brazil

Race diversity and virulence complexity ofPhytophthora infestans in Nepal

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