scholarly journals Characterization of Isolates of Phytophthora infestans from Tomato and Potato in North Carolina from 1993 to 1995

Plant Disease ◽  
1999 ◽  
Vol 83 (7) ◽  
pp. 633-638 ◽  
Author(s):  
Dawn E. Fraser ◽  
Paul B. Shoemaker ◽  
Jean B. Ristaino
Keyword(s):  
North Carolina ◽  
South Carolina ◽  
Phytophthora Infestans ◽  
Mating Type ◽  
The United States ◽  
Western North Carolina ◽  
New Genotype ◽  
The Us ◽  
Eastern North Carolina ◽  
Allozyme Genotype

Eighty-five isolates of Phytophthora infestans from 33 tomato and 8 potato fields in North Carolina, South Carolina, and Tennessee were collected from 1993 to 1995 and tested for mating type, sensitivity to metalaxyl, and allozyme genotype at glucose-6-phosphate isomerase (Gpi) and peptidase (Pep) loci. One isolate collected from potato in eastern North Carolina in 1994 was the A1 mating type, whereas all other isolates from potato and tomato were the A2 mating type. Six isolates were sensitive to metalaxyl (<40% growth at 1.0 μg of metalaxyl per ml), nineteen isolates were intermediate in sensitivity to metalaxyl (>40% growth at 1.0 μg of metalaxyl per ml and <40% growth at 100 μg of metalaxyl per ml), and sixty isolates were resistant to metalaxyl (<40% growth at 1.0 and 100 μg of metalaxyl per ml). Four different allozyme genotypes at the Gpi and Pep loci were identified. The single A1 isolate found on potato in eastern North Carolina had the dilocus allozyme genotype Gpi 86/100, Pep 92/100 and was identified as the US-1 genotype. Fifty-five isolates had the dilocus allozyme genotype Gpi 100/111, Pep 100/100 and were classified as the US-7 genotype, whereas twenty-four isolates were Gpi 100/111/122, Pep 100/100 and were classified as the US-8 genotype. Two isolates that were sensitive to meta-laxyl and seventeen isolates that were intermediate in sensitivity to metalaxyl were found among the US-7 and US-8 genotypes. In addition, five isolates had the allozyme genotype Gpi 100/100, Pep 92/100 (similar to the previously reported US-6 genotype), but they were the A2 mating type and either sensitive or intermediate in response to metalaxyl. These isolates composed a new genotype not previously reported in the United States and were designated as US-18. The US-7 genotype was more frequent on tomato in western North Carolina and the US-8 genotype was present on potato in eastern North Carolina, indicating that different inoculum sources are responsible for epidemics on the two crops in different regions of the state.

scholarly journals Phytophthora infestans Populations from Tomato and Potato in North Carolina Differ in Genetic Diversity and Structure

2002 ◽  
Vol 92 (11) ◽  
pp. 1189-1195 ◽  
Author(s):  
T. Wangsomboondee ◽  
C. Trout Groves ◽  
P. B. Shoemaker ◽  
M. A. Cubeta ◽  
J. B. Ristaino
Keyword(s):  
North Carolina ◽  
Phytophthora Infestans ◽  
Mitochondrial Haplotype ◽  
Banding Patterns ◽  
Tuber Blight ◽  
Genetic Diversity And Structure ◽  
The Us ◽  
Unique Restriction ◽  
Single Field ◽  
Allozyme Genotype

Phytophthora infestans causes a destructive disease on tomato and potato. In North Carolina (NC) potatoes are mostly grown in the east, whereas tomatoes are grown in the mountainous areas in the western part of the state. Five genotypes of P. infestans were identified from 93 and 157 isolates collected from tomato and potato over a 5 year period between 1993 and 1998. All isolates collected from potato in eastern NC were the US-8 genotype, whereas only a single isolate was the US-1 genotype. Tuber blight was found on immature daughter tubers in a single field in 1997, however infection on mature tubers was not observed. Within potato fields, a range of sensitivity to metalaxyl was observed among isolates but all were either intermediate or highly resistant to the fungicide. In contrast, isolates from tomatoes included previously reported US-7 and US-8 genotypes and two new genotypes called US-18 and US-19 (A2 mating type, allozyme genotype Gpi 100/100 and Pep 92/100). These genotypes had unique restriction fragment length polymorphism banding patterns, were sensitive to metalaxyl, and have not been reported elsewhere. All genotypes, with the exception of the US-1, were the Ia mitochondrial haplotype. Thus, isolates of P. infestans from tomato were more genetically diverse over time in NC than those from potato and include two new genotypes that are sensitive to metalaxyl.

scholarly journals Genetic Change Within Populations of Phytophthora infestans in the United States and Canada During 1994 to 1996: Role of Migration and Recombination

1998 ◽  
Vol 88 (9) ◽  
pp. 939-949 ◽  
Author(s):  
Stephen B. Goodwin ◽  
Christine D. Smart ◽  
Robert W. Sandrock ◽  
Kenneth L. Deahl ◽  
Zamir K. Punja ◽  
...  
Keyword(s):  
United States ◽  
Sexual Reproduction ◽  
Phytophthora Infestans ◽  
High Sensitivity ◽  
The United States ◽  
Rapid Identification ◽  
Mating Types ◽  
Long Distance ◽  
New Genotype ◽  
The Us

Dramatic changes occurred within populations of Phytophthora infestans in the United States and Canada from 1994 through 1996. Occurrence of the US-8 genotype, detected rarely during 1992 and 1993, increased rapidly and predominated in most regions during 1994 through 1996. US-7, which infected both potato and tomato and made up almost 50% of the sample during 1993, was detected only rarely among 330 isolates from the United States analyzed during 1994. It was not detected at all in more limited samples from 1996. Thus, ability to infect both potato and tomato apparently did not increase the fitness of this genotype relative to US-8, as predicted previously. US-1, the previously dominant genotype throughout the United States and Canada, made up 8% or less of the samples analyzed during 1994 through 1996. A few additional genotypes were detected, which could indicate the beginnings of sexual reproduction of P. infestans within the United States and Canada. However, clonal reproduction still predominated in all locations sampled; opportunities for sexual reproduction probably were limited, because the A1 and A2 mating types usually were separated geographically. The high sensitivity of the US-1 genotype to the fungicide metalaxyl also could have reduced opportunities for contact between the mating types in fields where this compound was applied. The previous correlation between metalaxyl sensitivity and genotype was confirmed and extended to a new genotype, US-17: all US-1 isolates tested were sensitive; all isolates of the US-7, US-8, and US-17 genotypes tested to date have been resistant. Isolates of P. capsici and P. erythroseptica, two other species often found on tomato and potato, could be easily distinguished from each other and from P. infestans using a simple allozyme assay for the enzyme glucose-6-phosphate isomerase. This technique could be useful for rapid identification of species, in addition to genotype of P. infestans. It generally was not possible to predict which genotypes would be present in a location from 1 year to the next. Long-distance movement of US-8 in seed tubers was documented, and this was probably the primary means for the rapid spread of this genotype from 1993 through 1996.

scholarly journals Characterization of Phytophthora infestans Populations in Western Washington

Plant Disease ◽  
1999 ◽  
Vol 83 (5) ◽  
pp. 423-428 ◽  
Author(s):  
A. E. Dorrance ◽  
D. A. Inglis ◽  
M. L. Derie ◽  
C. R. Brown ◽  
S. B. Goodwin ◽  
...  
Keyword(s):  
Phytophthora Infestans ◽  
Mating Type ◽  
The United States ◽  
Dna Fingerprint ◽  
Multilocus Genotype ◽  
Sexual Recombination ◽  
The Us ◽  
Western Washington ◽  
Single Field

The first detection in the United States of isolates of Phytophthora infestans having metalaxyl insensitivity and complex pathotypes occurred in western Washington during the early 1990s. To determine the genetic structure of the current population in western Washington, a total of 115 isolates of P. infestans were obtained during 1996 from infected tubers or foliage of potato, tomato, nightshade, and bittersweet throughout the region. An additional 45 isolates were collected from a single field. Based on mating type, metalaxyl-insensitivity, and molecular markers (allozymes of glucose-6-phosphate isomerase, peptidase, and RG57 DNA fingerprint), all of the isolates were A1 mating type and had the US-11 multilocus genotype. Analyses of an additional 120 isolates collected during 1997 from potato, tomato, and nightshade were performed. As in 1996, US-11 was the predominant genotype detected on all three hosts. However, three additional A2 mating type genotypes were also detected: US-7, US-8, and US-14. These three genotypes represent the first A2 mating type isolates detected in western Washington. Most of a subset of 60 isolates infected 4 to 7 of the 10 potato differentials tested. This included 90% of the isolates collected in 1996 (all US-11), plus 72% of the US-11 and 100% of the US-8 and US-14 isolates collected during 1997. Virulence phenotypes in this region are complex even without the selection pressure of R-genes in the local commercial cultivars. The apparent increase in genetic variation observed in populations of P. infestans in western Washington from 1996 to 1997 most likely occurred by migration rather than by sexual recombination.

scholarly journals First Report of Late Blight Caused by Phytophthora infestans Clonal Lineage US-23 on Tomato and Potato in Atlantic Canada

Plant Disease ◽  
2014 ◽  
Vol 98 (3) ◽  
pp. 426-426 ◽  
Author(s):  
C. P. Wijekoon ◽  
R. D. Peters ◽  
K. I. Al-Mughrabi ◽  
L. M. Kawchuk
Keyword(s):  
United States ◽  
Late Blight ◽  
New Brunswick ◽  
Phytophthora Infestans ◽  
Mating Type ◽  
Prince Edward Island ◽  
The United States ◽  
Clonal Lineage ◽  
Eastern Canada ◽  
The Us

Phytophthora infestans (Mont.) de Bary has produced significant losses in potato and tomato yield and quality during recent late blight epidemics in North America. During the 1990s, more aggressive and genetically diverse P. infestans genotypes migrated to Canada and the United States (2). For example, US-8 became predominant and was found to be more aggressive in potato than previous clonal lineages of P. infestans. Recent P. infestans genotypes in potato and tomato plants from the United States and Canada include US-22, US-23, and US-24 representing clonal lineages with unique epidemiological characteristics (2,3,4). Characteristic phenotypic traits have been described for P. infestans clonal lineages US-8, US-22, US-23, and US-24 based on the mating type, mefenoxam sensitivity, pathogenicity, and rate of germination suggesting an association between phenotypic variations and the genotype (1,4). Analysis of P. infestans isolates collected in Canada during 2010 revealed the presence of the US-23 clonal lineage in four different areas of western Canada but not in eastern Canada (4). Isolates of P. infestans collected from eastern Canada for several years prior to 2011 were all US-8 A2 mating type. Isolation and analysis of 98 P. infestans isolates in 2011 from New Brunswick and Prince Edward Island followed standard procedures (2,3,4). Results confirmed the presence of the US-23 clonal lineage in Atlantic Canada on potato and tomato leaves with late blight symptoms, increasing the genetic complexity of P. infestans in eastern Canada. Allozyme banding patterns at the glucose-6-phosphate isomerase (Gpi) locus showed a 100/100 profile in 10 P. infestans isolates, consistent with the US-23 clonal lineage (2,3,4). Furthermore, in vitro mefenoxam sensitivity was observed in all 10 P. infestans US-23 isolates from New Brunswick and Prince Edward Island. Mating type assays confirmed the isolates were of the A1 mating type. RFLP analysis of EcoR1-digested genomic DNA using the multilocus RG57 sequence as a probe produced the DNA pattern 1, 2, 5, 6, 10, 13, 14, 17, 20, 21, 24, 24a, 25, indicative of US-23 (2,4). Microsatellite analysis using polymorphic markers on New Brunswick and Prince Edward Island P. infestans isolates produced the Pi4B 213/217 bp, D13 134 bp, and PiG11 140/155 bp profile of P. infestans US-23 (1). These results show the presence of the P. infestans A1 and A2 mating types in New Brunswick and Prince Edward Island, which increases the probability of sexual recombination. To our knowledge, this is the first report of P. infestans clonal lineage US-23 causing late blight in New Brunswick and Prince Edward Island, increasing the genetic diversity from previous years in eastern Canada and underscoring the annual fluctuation occurring in the population composition. References: (1) G. Danies et al. Plant Dis. 97:873, 2013. (2) S. B. Goodwin et al. Phytopathology 84:553, 1994. (3) C. H. Hu et al. Plant Dis. 96:1323, 2012. (4) M. L. Kalischuk et al. Plant Dis. 96:1729, 2012.

The Anti-Aryan Moment: Decolonization, Diplomacy, and Race in Late Pahlavi Iran

2021 ◽  
Vol 53 (4) ◽  
pp. 691-702
Author(s):  
Firoozeh Kashani-Sabet
Keyword(s):  
South Carolina ◽  
World War Ii ◽  
Cold War ◽  
Soviet Union ◽  
The United States ◽  
World War ◽  
The Soviet Union ◽  
The Us ◽  
Anglo American ◽  
The Cold War

In 1946, the entertainer and activist Paul Robeson pondered America's intentions in Iran. In what was to become one of the first major crises of the Cold War, Iran was fighting a Soviet aggressor that did not want to leave. Robeson posed the question, “Is our State Department concerned with protecting the rights of Iran and the welfare of the Iranian people, or is it concerned with protecting Anglo-American oil in that country and the Middle East in general?” This was a loaded question. The US was pressuring the Soviet Union to withdraw its troops after its occupation of the country during World War II. Robeson wondered why America cared so much about Soviet forces in Iranian territory, when it made no mention of Anglo-American troops “in countries far removed from the United States or Great Britain.” An editorial writer for a Black journal in St. Louis posed a different variant of the question: Why did the American secretary of state, James F. Byrnes, concern himself with elections in Iran, Arabia or Azerbaijan and yet not “interfere in his home state, South Carolina, which has not had a free election since Reconstruction?”

scholarly journals Fungicide Sensitivity of U.S. Genotypes of Phytophthora infestans to Six Oomycete-Targeted Compounds

Plant Disease ◽  
2015 ◽  
Vol 99 (5) ◽  
pp. 659-666 ◽  
Author(s):  
Amanda Saville ◽  
Kim Graham ◽  
Niklaus J. Grünwald ◽  
Kevin Myers ◽  
William E. Fry ◽  
...  
Keyword(s):  
United States ◽  
Phytophthora Infestans ◽  
The United States ◽  
Effective Concentration ◽  
Response Curves ◽  
Baseline Sensitivity ◽  
Fungicide Sensitivity ◽  
The Past ◽  
The Us

Phytophthora infestans causes potato late blight, an important and costly disease of potato and tomato crops. Seven clonal lineages of P. infestans identified recently in the United States were tested for baseline sensitivity to six oomycete-targeted fungicides. A subset of the dominant lineages (n = 45) collected between 2004 and 2012 was tested in vitro on media amended with a range of concentrations of either azoxystrobin, cyazofamid, cymoxanil, fluopicolide, mandipropamid, or mefenoxam. Dose-response curves and values for the effective concentration at which 50% of growth was suppressed were calculated for each isolate. The US-8 and US-11 clonal lineages were insensitive to mefenoxam while the US-20, US-21, US-22, US-23, and US-24 clonal lineages were sensitive to mefenoxam. Insensitivity to azoxystrobin, cyazofamid, cymoxanil, fluopicolide, or mandipropamid was not detected within any lineage. Thus, current U.S. populations of P. infestans remained sensitive to mefenoxam during the displacement of the US-22 lineage by US-23 over the past 5 years.

Phytophthora infestans mating type A2. [Distribution map].

1996 ◽  
Author(s):  
Keyword(s):  
North Carolina ◽  
Northern Ireland ◽  
Phytophthora Infestans ◽  
Mating Type ◽  
West Bengal ◽  
Russian Far East ◽  
Far East ◽  
Distribution Map ◽  
East Siberia ◽  
New Distribution

Abstract A new distribution map is provided for Phytophthora infestans (Mont.) de Bary mating type A2. Hosts: Potato (Solanum tuberosum), tomato (Lycopersicon esculentum) and others. Information is given on the geographical distribution in Canada, British Columbia, Egypt, Estonia, France, Mainland France, Germany, India, Himachal Pradesh, Meghalaya, West Bengal, Indonesia, Ireland, Israel, Japan, Korea Republic, Mexico, Netherlands, Poland, Russia, Russia (European), Russian Far East, Siberia, Switzerland, UK, England and Wales, Northern Ireland, Scotland, USA, Florida, North Carolina, Pennsylvania, Texas, Washington.

scholarly journals Consumer Drivers of Muscadine Wine Purchase Decisions

Beverages ◽  
2018 ◽  
Vol 4 (4) ◽  
pp. 98 ◽  
Author(s):  
Bonnie Canziani ◽  
Erick Byrd ◽  
James Boles
Keyword(s):  
North Carolina ◽  
Spillover Effects ◽  
The United States ◽  
Wine Industry ◽  
Us South ◽  
Consumer Panel ◽  
The Social ◽  
The Us ◽  
Quota Sampling ◽  
Muscadine Grapes

Muscadine wine, fresh muscadine grapes, and other derivatives have enjoyed a heritage niche for decades in the Southeast. Muscadine growers in North Carolina in the United States (US) have asked whether the purchase of muscadine wine is linked to consumption of the fruit itself or even familiarity with other muscadine-based products in terms of spillover effects. The authors explored the interdependency between the market for fresh muscadine grapes and muscadine wine purchase. Consumer panel data were obtained from a State of North Carolina agency with oversight of the grape and wine industry; the agency contracted quota sampling of online consumers from six states in the US South. A total of 543 cases were used in the present study. The Statistical Package for the Social Sciences (SPSS)® was employed in analysis. Results show that prior muscadine wine knowledge and knowledge of other muscadine products, e.g., jams, juices, smoothies, sauces, and health/beauty products were significant factors associated with buying muscadine wine. Beliefs about muscadine grapes as a healthy ingredient showed a slight influence, while direct experience with fresh muscadines and consumer attitudes towards buying local or US products were insignificant. Therefore, marketing efforts should focus on increasing consumer exposure to and knowledge of muscadine wine and other muscadine related products.

scholarly journals Classifying the Relative Host Reaction in Potato Cultivars and Breeding Lines to the US-8 Strain of Phytophthora infestans in Minnesota

Plant Disease ◽  
2003 ◽  
Vol 87 (8) ◽  
pp. 983-990 ◽  
Author(s):  
J. C. Jenkins ◽  
R. K. Jones
Keyword(s):  
Late Blight ◽  
Phytophthora Infestans ◽  
Rank Correlation ◽  
The United States ◽  
Spearman Rank Correlation ◽  
Breeding Lines ◽  
Spearman Rank ◽  
Progress Curve ◽  
Tuber Blight ◽  
The Us

A total of 32 commercial cultivars grown in the United States and 15 potato breeding lines and non-U.S. cultivars were evaluated at Rosemount, MN for their reaction to the US-8 strain of Phytophthora infestans. Commercial red-, russet-, and white-skinned cultivars tested in the commercial cultivar trial (COMC) in 1996 and 1997 were susceptible (S) to moderately susceptible (MS) to this organism, except for Elba, which ranked as moderately resistant (MR). Yellow-fleshed cvs. Hertha, Santé, and Agria were screened in the late blight nursery (LB1) in 1997 and 1998 and classified as S to MS while Island Sunshine, Brador, and Aziza were classified as MR. The Scottish breeding line G6582-3 and U.S. breeding lines A90586-11, AWN86514-2, AWN85624-5, B0692-4, B0718-3, and B0767-2 were classified as resistant (R). Comparison among entries was based on the area under the disease progress curve (AUDPC). Spearman rank correlation for AUDPC in the 1996 and 1997 COMC trials at 14 to 18 days after inoculation (r = 0.65, P < 0.01) was greater than any other interval tested. The Spearman rank correlation for AUDPC in the 1997 and 1998 LB1 trials at 14 to 18 days after inoculation was r = 0.87, P < 0.01 and increased only slightly in successive assessment dates, suggesting that, in Minnesota, effective evaluation of the foliar infection of late blight can occur at 18 days after inoculation or later. The average tuber blight incidence for the COMC trials at harvest was 10.0% in 1996 and 9.7% in 1997. The average tuber blight incidence for the LB1 trials at harvest was 4.3% in 1997 and 14.6% in 1998. Pearson correlations between tuber blight incidence and foliar disease for the COMC trials was very low; however, for the LBl trials, it was significant in both 1997 (r = 0.53, P < 0.01) and 1998 (r = 0.53, P < 0.01). Asymptomatic tubers harvested from the COMC trials developed additional tuber blight when stored 28 days at ambient temperatures and still more when stored for another 5 months at 5°C. Surviving tubers of nine entries were planted in field trials during 1997 and 1998 to determine if plants that develop from tubers exposed to P. infestans could manifest late blight in the subsequent season. Late blight failed to develop throughout the trials in either year.

scholarly journals Characterization of Phytophthora infestans in Wisconsin from 1993 to 1995

Plant Disease ◽  
1998 ◽  
Vol 82 (4) ◽  
pp. 434-436 ◽  
Author(s):  
K. D. Marshall-Farrar ◽  
M. McGrath ◽  
R. V. James ◽  
W. R. Stevenson
Keyword(s):  
Solanum Tuberosum ◽  
Late Blight ◽  
Phytophthora Infestans ◽  
Mating Type ◽  
Production Problem ◽  
Significant Production ◽  
Allozyme Genotype ◽  
Late Blight Of Potato

Late blight of potato (Solanum tuberosum), caused by Phytophthora infestans, recently reappeared in Wisconsin and was a significant production problem in 1994. P. infestans isolates collected in Wisconsin from 1993 to 1995 were characterized for the following traits: mating type, sensitivity to metalaxyl, and allozyme genotype for Glucose-6-phosphate isomerase (Gpi). Characterization of these isolates revealed that a new, more aggressive population (A2 mating type, metalaxyl resistant, and Gpi genotype 100/111/122) is displacing the old population (A1 mating type, metalaxyl sensitive, and Gpi genotype 86/100) in Wisconsin.

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