scholarly journals Genetic Diversity of Phytophthora infestans sensu lato in Ecuador Provides New Insight Into the Origin of This Important Plant Pathogen

2004 ◽  
Vol 94 (2) ◽  
pp. 154-162 ◽  
Author(s):  
N. E. Adler ◽  
L. J. Erselius ◽  
M. G. Chacón ◽  
W. G. Flier ◽  
M. E. Ordoñez ◽  
...  
Keyword(s):  
Phytophthora Infestans ◽  
Length Polymorphism ◽  
Fragment Length ◽  
Fragment Length Polymorphism ◽  
Geographic Origin ◽  
Current Theory ◽  
Clonal Lineage ◽  
Complete Collection ◽  
Pathogen Populations ◽  
Andean Highlands

The metapopulation structure of Phytophthora infestans sensu lato is genetically diverse in the highlands of Ecuador. Previous reports documented the diversity associated with four putative clonal lineages of the pathogen collected from various hosts in the genus Solanum. This paper simultaneously analyzes diversity of the complete collection of isolates, including a large number that had not yet been reported. This analysis confirmed the existence of three pathogen populations, which all appear to be clonal lineages, and that correspond to those previously reported as US-1, EC-1, and EC-3. No evidence was found from the analyses of recently collected isolates that would contradict earlier reports about these three lineages. In contrast, new data from a group of isolates from several similar hosts caused us to modify the previous description of clonal lineage EC-2 and its previously proposed hosts, S. brevifolium and S. tetrapetalum. Given the uncertainty associated with the identification of these hosts, which all belong to the section Anarrhichomenum, we refer to them as the Anarrhichomenum complex, pending further taxonomic clarification. New pathogen genotypes associated with the Anarrhichomenum complex were isolated recently that are A1 mating type and Ia mitochondrial DNA (mtDNA) haplotype, and therefore differ from the previously described EC-2 lineage, which is A2 and Ic, respectively. Because of uncertainty on host identification, we do not know if the new genotypes are limited to one host species and therefore represent yet another host-adapted clonal lineage. For now, we refer to the new genotypes and previously described EC-2 genotypes, together, as the pathogen group attacking the Anarrhichomenum complex. Two A2 isolates identical to the previously described EC-2 archetype were collected from severely infected plants of pear melon (S. muricatum). Pear melon is generally attacked by US-1, and this is the first clear case we have documented in which two distinct pathogen genotypes have caused severe epidemics on the same host. Based on presence of unique marker alleles (restriction fragment length polymorphism [RFLP] and mtDNA) and genetic similarity analysis using RFLP and amplified fragment length polymorphism data, EC-3 and isolates from the Anarrhichomenum complex are genetically distinct from all genotypes of P. infestans that have been reported previously. No current theory of historical migrations for this pathogen can adequately support a Mexican origin for EC-3 and genotypes of the Anarrhichomenum complex and they may, therefore, be palaeoendemic to the Andean highlands. To date, we have identified 15 hosts in the genus Solanum, in addition to the Anarrhichomenum complex, and some unidentified species of P. infestans sensu lato in Ecuador. Five of the Solanum hosts are cultivated. One isolate was collected from Brugmansia sanguinea, which represents the first report from Ecuador of a host of this pathogen that is not in the genus Solanum. However, P. infestans sensu lato was only found on flower petals of B. sanguinea. This study provides new insights into the population structure of highly specialized genotypes of P. infestans sensu lato in the Andean highlands. The results are discussed in light of previous hypotheses regarding the geographic origin of the pathogen.

scholarly journals High-Resolution Genotyping of Streptococcus pyogenesSerotype M1 Isolates by Fluorescent Amplified-Fragment Length Polymorphism Analysis

1999 ◽  
Vol 37 (6) ◽  
pp. 1948-1952 ◽  
Author(s):  
Meeta Desai ◽  
Androulla Efstratiou ◽  
Robert George ◽  
John Stanley
Keyword(s):  
Length Polymorphism ◽  
Fragment Length ◽  
Fragment Length Polymorphism ◽  
Geographic Origin ◽  
Amplified Fragment Length Polymorphism ◽  
Discriminatory Power ◽  
Polymorphism Analysis ◽  
Worldwide Distribution ◽  
High Discriminatory Power ◽  
Typing Methods

We have used fluorescent amplified-fragment length polymorphism (FAFLP) analysis to subtype clinical isolates of Streptococcus pyogenes serotype M1. Established typing methods define most M1 isolates as members of a clone that has a worldwide distribution and that is strongly associated with invasive diseases. FAFLP analysis simultaneously sampled 90 to 120 loci throughout the M1 genome. Its discriminatory power, precision, and reproducibility were compared with those of other molecular typing methods. Irrespective of disease symptomatology or geographic origin, the majority of the clinical M1 isolates shared a single ribotype, pulsed-field gel electrophoresis macrorestriction profile, and emm1 gene sequence. Nonetheless, among these isolates, FAFLP analysis could differentiate 17 distinct profiles, including seven multi-isolate groups. The FAFLP profiles of M1 isolates reproducibly exhibited between 1 and more than 20 amplified fragment differences. The high discriminatory power of genotyping by FAFLP analysis revealed genetic microheterogeneity and differentiated otherwise “identical” M1 isolates as members of a clone complex.

scholarly journals Genetic Structure of Peruvian Populations of Phytophthora infestans

2001 ◽  
Vol 91 (10) ◽  
pp. 956-965 ◽  
Author(s):  
Willmer G. Perez ◽  
J. Soledad Gamboa ◽  
Yesenia V. Falcon ◽  
Mario Coca ◽  
Rubi M. Raymundo ◽  
...  
Keyword(s):  
Phytophthora Infestans ◽  
Length Polymorphism ◽  
Fragment Length ◽  
Fragment Length Polymorphism ◽  
Peruvian Andes ◽  
The North ◽  
Metalaxyl Sensitivity ◽  
Andean Countries ◽  
Key Sites ◽  
Late Blight Pathogen

Isolates of the late blight pathogen Phytophthora infestans (n = 327) from the central to southern Peruvian Andes were systematically collected in 1997 to 1999 and analyzed to determine the pathogen's population structure at its host's center of diversity. No isolates of the A2 mating type were detected. Cluster analysis of DNA fingerprinting data indicated that the collection consisted of five major groups that were interpreted to be clonal lineages. Two of the lineages (US-1 and EC-1) have been previously described, and three (PE-3, 5, and 6) are described here for the first time. Collections from three areas in the central Peruvian Andes, including two key sites used in an international potato breeding program, consisted of isolates of the EC-1 lineage, which has been reported to dominate the pathogen population in Andean countries to the north of Peru. The collections from Cusco and Puno were more diverse. More than one lineage was detected in 10 of the 20 fields sampled in Cusco. Data on virulence, metalaxyl sensitivity, and band data for allozymes, mitochondrial DNA, and ipiB1 suggested that PE-3 may have been produced through recombination events between US-1 and EC-1. Restriction fragment length polymorphism and amplified fragment length polymorphism marker data were not consistent with this hypothesis.

Structure of worldwide populations of Lasioderma serricorne (Coleoptera: Anobiidae) as revealed by amplified fragment length polymorphism profiles

2006 ◽  
Vol 96 (2) ◽  
pp. 111-116 ◽  
Author(s):  
M.P. Blanc ◽  
N. Lugon-Moulin ◽  
C. Panighini ◽  
H. Pijnenburg ◽  
L. Rossi
Keyword(s):  
Population Study ◽  
Length Polymorphism ◽  
Fragment Length ◽  
Fragment Length Polymorphism ◽  
Geographic Origin ◽  
Amplified Fragment Length Polymorphism ◽  
Dna Polymorphisms ◽  
Lasioderma Serricorne ◽  
Insect Dispersal ◽  
Geographical Regions

AbstractThe cigarette beetle Lasioderma serricorne through transportation affects the infestation of stored tobacco. Using amplified fragment length polymorphism (AFLP), DNA polymorphisms were assessed in 16 populations of L. serricorne collected from 15 countries. The dendrograms constructed from profile distance matrices revealed well-supported colony clusters. There was no clear clustering as a function of the geographic origin of the samples. The results suggest extensive insect dispersal among geographical regions due to movement of infested commodities worldwide. This first AFLP population study of a stored-product insect demonstrates the potential of AFLP for distinguishing L. serricorne populations.

scholarly journals Genetic Mapping of Ph-2, a Single Locus Controlling Partial Resistance to Phytophthora infestans in Tomato

1998 ◽  
Vol 11 (4) ◽  
pp. 259-269 ◽  
Author(s):  
Philippe Moreau ◽  
Philippe Thoquet ◽  
Jocelyne Olivier ◽  
Henri Laterrot ◽  
Nigel Grimsley
Keyword(s):  
Genetic Analysis ◽  
Late Blight ◽  
Phytophthora Infestans ◽  
Length Polymorphism ◽  
Fragment Length ◽  
Distal Part ◽  
Fragment Length Polymorphism ◽  
Bulked Segregant Analysis ◽  
Introgression Line ◽  
Chromosome 10

Late blight caused by the fungal pathogen Phytophthora infestans is one of the most important diseases of potato (Solanum tuberosum) and tomato (Lycopersicon esculentum). Genetic analysis of the resistance to this pathogen was performed on an F2 progeny of 322 plants derived from a cross between the tomato line L. esculentum var. Hawaii7996 susceptible to late blight and the resistant wild relative L. pimpinellifolium WVa700. Qualitative and quantitative analyses of the resistance with restriction fragment length polymorphism markers spanning the genome showed that this resistance was controlled by a single, incompletely dominant allele, Ph-2, present on the distal part of the long arm of chromosome 10 in an interval of 8.4 cM flanked by markers CP105 and TG233. Genetic analysis of F2 progeny from a second cross between an L. esculentum introgression line IL10-3 carrying a homozygous L. pennellii segment spanning the distal part of the long arm of chromosome 10 and WVa700 confirmed the map location, but high suppression of recombination was observed in this cross in the introgressed fragment. A high-resolution genetic linkage map of the chromosomal region surrounding Ph-2 was initiated to permit future map-based cloning of this gene. Amplified fragment length polymorphism markers closely linked to Ph-2 were screened by bulked segregant analysis.

scholarly journals Diversidad genética de aislados de Phytophthora infestans colectados en zonas productoras de papa y tomate de Guatemala

2018 ◽  
Vol 5 (2) ◽  
pp. 151-161
Author(s):  
Jose Alejandro Ruiz-Chutan ◽  
Julio E. Berdúo-Sandoval ◽  
Amilcar Sánchez-Pérez
Keyword(s):  
Phytophthora Infestans ◽  
Length Polymorphism ◽  
Fragment Length ◽  
Fragment Length Polymorphism ◽  
Amplified Fragment Length Polymorphism ◽  
Arithmetic Mean ◽  
Group Method ◽  
Pair Group ◽  
Unweighted Pair Group Method

Phytophthora infestans (Mont) DeBary es el agente causal de la enfermedad conocida como tizón tardío, la cual ha sido catalogada como la enfermedad de plantas más devastadora reportada en la historia de la humanidad. Este patógeno afecta plantas de importancia económica de la familia Solanaceae, como el tomate y la papa. P. infestans es un oomicete heterotálico y necesita de dos tipos de apareamiento, A1 y A2, para presentar una reproducción sexual, la cual es la principal vía por la que este patógeno incrementa su grado de diversidad, a través de una recombinación de su material genético, que representa el mayor desafío para el manejo de la enfermedad. Este estudio determinó el nivel de variabilidad genética, a través del marcador molecular amplified fragment length polymorphism (AFLP), de 22 aislados de P. infestans colectados en diferentes zonas productoras de papa y tomate. Con el perfil de bandas generado por el marcador molecular, se realizó un análisis cluster creando un dendograma de tipo unweighted pair group method with arithmetic mean (UPGMA), con el índice de Dice, mediante una matriz de distancias genéticas. Los aislados fueron situados en tres grupos principales, los cuales responden al lugar de procedencia y al tipo de planta hospedera. 

scholarly journals Distribution of Rose Black Spot (Diplocarpon rosae) Genetic Diversity in Eastern North America Using Amplified Fragment Length Polymorphism and Implications for Resistance Screening

2007 ◽  
Vol 132 (4) ◽  
pp. 534-540 ◽  
Author(s):  
Vance M. Whitaker ◽  
Stan C. Hokanson ◽  
James Bradeen
Keyword(s):  
Genetic Diversity ◽  
North America ◽  
Length Polymorphism ◽  
Fragment Length ◽  
Fragment Length Polymorphism ◽  
Geographic Origin ◽  
Black Spot ◽  
Eastern North America ◽  
Single Spore ◽  
Diplocarpon Rosae

Black spot, incited by the fungus Diplocarpon rosae Wolf, is the most significant disease problem of landscape roses (Rosa hybrida L.) worldwide. The documented presence of pathogenic races necessitates that rose breeders screen germplasm with isolates that represent the range of D. rosae diversity for their target region. The objectives of this study were to characterize the genetic diversity of single-spore isolates from eastern North America and to examine their distribution according to geographic origin, host of origin, and race. Fifty isolates of D. rosae were collected from roses representing multiple horticultural classes in disparate locations across eastern North America and analyzed by amplified fragment length polymorphism. Considerable marker diversity among isolates was discovered, although phenetic and cladistic analyses revealed no significant clustering according to host of origin or race. Some clustering within collection locations suggested short-distance dispersal through asexual conidia. Lack of clustering resulting from geographic origin was consistent with movement of D. rosae on vegetatively propagated roses. Results suggest that field screening for black spot resistance in multiple locations may not be necessary; however, controlled inoculations with single-spore isolates representing known races is desirable as a result of the inherent limitations of field screening.

scholarly journals Genetic variation between Colletotrichum lindemuthianum isolates

2017 ◽  
Vol 38 (SI 2 - 6th Conf EFPP 2002) ◽  
pp. 378-380
Author(s):  
K.I. Ansari ◽  
N. Palacios ◽  
C. Araya ◽  
T. Langin ◽  
D. Egan ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Length Polymorphism ◽  
Fragment Length ◽  
Fragment Length Polymorphism ◽  
Geographic Origin ◽  
Colletotrichum Lindemuthianum ◽  
Molecular Profile ◽  
Aflp Analysis ◽  
Huge Variation

We characterized the genetic diversity of seventy-three C. lindemuthianum isolates collected from 10 different countries by Amplified Fragment Length Polymorphism (AFLP) analysis. The results of this research highlighted the fact that there is huge variation in the genetic diversity between isolates from different countries. The molecular profile of the isolates showed correlation with geographic origin of the isolates.

Sign in / Sign up

Export Citation Format

Share Document