Phylogenetic Analysis, Vegetative Compatibility, Virulence, and Fungal Filtrates of Leaf Curl Pathogen Colletotrichum fioriniae From Celery

Leaf curl of celery, caused by Colletotrichum acutatum sensu lato, has been reported in the U.S. A multi-locus phylogenetic analysis with three genes was conducted with a collection of isolates from celery (23) and non-celery (29) hosts to evaluate their taxonomic position within C. acutatum sensu lato. The three DNA regions used for phylogenetic analysis included the introns of glutamine synthase (GS) and glyceraldehyde-3-phosphate dehydrogenase (GPDH), and the partial sequence of the histone3 (his3) gene. Moreover, celery and non-celery isolates were evaluated for vegetative compatibility and pathogenicity on celery. Culture filtrates from celery and non-celery isolates were also evaluated for their ability to reproduce leaf curl symptoms. A total of 23 celery isolates were evaluated based on phylogenetic analysis, which showed that all celery isolates were closely related and belonged to the newly described species C. fioriniae. The celery isolates were grouped into six vegetative compatibility groups indicating the population was not clonal. Twenty two of 23 isolates of C. fioriniae from celery and other hosts (26 of 29) caused leaf curl symptoms. Isolates of C. acutatum, C. nymphaeae, and C. godetiae were pathogenic but did not cause leaf curl symptoms. Isolates of C. lupini, C. johnstonii, and C. gloeosporioides were not pathogenic on celery. In addition, cell-free fungal culture filtrates caused leaf curl symptoms on celery indicating that certain isolates produce a metabolite that can cause leaf curl symptoms on celery, possibly indole acetic acid (IAA).

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Characterization of Colletotrichum acutatum Causing Anthracnose of Anemone (Anemone coronaria L.)

Applied and Environmental Microbiology ◽

10.1128/aem.66.12.5267-5272.2000 ◽

2000 ◽

Vol 66 (12) ◽

pp. 5267-5272 ◽

Cited By ~ 31

Author(s):

Stanley Freeman ◽

Ezra Shabi ◽

Talma Katan

Keyword(s):

Western Europe ◽

Pcr Amplification ◽

Vegetative Compatibility ◽

Colletotrichum Acutatum ◽

Vegetative Compatibility Groups ◽

The Third ◽

Artificial Inoculations ◽

Species Specific ◽

Arbitrarily Primed Pcr

ABSTRACT Anthracnose, or leaf-curl disease of anemone, caused byColletotrichum sp., has been reported to occur in Australia, western Europe, and Japan. Symptoms include tissue necrosis, corm rot, leaf crinkles, and characteristic spiral twisting of floral peduncles. Three epidemics of the disease have been recorded in Israel: in 1978, in 1990 to 1993, and in 1996 to 1998. We characterized 92Colletotrichum isolates associated with anthracnose of anemone (Anemone coronaria L.) for vegetative compatibility (72 isolates) and for molecular genotype (92 isolates) and virulence (4 isolates). Eighty-six of the isolates represented the three epidemics in Israel, one isolate was from Australia, and five isolates originated from western Europe. We divided these isolates into three vegetative-compatibility groups (VCGs). One VCG (ANE-A) included all 10 isolates from the first and second epidemics, and 13 of 62 examined isolates from the third epidemic in Israel, along with the isolate from Australia and 4 of 5 isolates from Europe. Another VCG (ANE-F) included most of the examined isolates (49 of the 62) from the third epidemic, as well as Colletotrichum acutatum from strawberry, in Israel. Based on PCR amplification with species-specific primers, all of the anemone isolates were identified as C. acutatum. Anemone and strawberry isolates of the two VCGs were genotypically similar and indistinguishable when compared by arbitrarily primed PCR of genomic DNA. Only isolate NL-12 from The Netherlands, confirmed as C. acutatum but not compatible with either VCG, had a distinct genotype; this isolate represents a third VCG of C. acutatum. Isolates from anemone and strawberry could infect both plant species in artificial inoculations. VCG ANE-F was recovered from natural infections of both anemone and strawberry, but VCG ANE-A was recovered only from anemone. This study of C. acutatum from anemone illustrates the potential of VCG analysis to reveal distinct subspecific groups within a pathogen population which appears to be genotypically homogeneous by molecular assays.

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Vegetative Compatibility Groups and Parasexual Segregation in Colletotrichum acutatum Isolates Infecting Different Hosts

Phytopathology ◽

10.1094/phyto-12-10-0327 ◽

2011 ◽

Vol 101 (8) ◽

pp. 923-928 ◽

Cited By ~ 11

Author(s):

Claudinéia Conationi da Silva Franco ◽

Juliane Rocha de Sant' Anna ◽

Lúcia Jacovozzi Rosada ◽

Edilson Nobuyoshi Kaneshima ◽

José Renato Stangarlin ◽

...

Keyword(s):

Genetic Variability ◽

Vegetative Compatibility ◽

Colletotrichum Acutatum ◽

Diploid Strain ◽

Alternative Source ◽

Parasexual Cycle ◽

Wild Isolate ◽

Vegetative Compatibility Groups ◽

Nit Mutants ◽

First Time

Heterokaryosis is an important mechanism which provides genetic variability increase in filamentous fungi. In order to assess the diversity of vegetative compatibility reactions existing among Colletotrichum acutatum isolates derived from different hosts, complementary nit mutants of each isolate were obtained and paired in all possible combinations. Vegetative compatibility groups (VCG) were identified among the isolates according to their ability to form viable heterokaryons. Seven VCGs were identified among the isolates, one of which contained isolates from different hosts. VCGs 2 and 6 contained two and three members, respectively; VCG-3 contained four members, and four VCGs (1, 4, 5, and 7) contained a single one. This study shows, for the first time, the isolation and the parasexual segregation of a heterozygous diploid sector derived from the heterokaryon formed with nit mutants from VCG-6. Diploid, named DE-3, showed nit+ phenotype and growth rate similar to the parental wild isolate. When inoculated in the presence of the haploidizing agent benomyl, the diploid strain produced parasexual haploid segregants exhibiting the nit phenotypes of the crossed mutants. Since viable heterokaryons and diploid may be formed among vegetative compatible isolates of C. acutatum, this study suggests that the parasexual cycle may be an alternative source of genetic variability in C. acutatum isolates.

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Genetic Variability of Cercospora coffeicola from Organic and Conventional Coffee Plantings, Characterized by Vegetative Compatibility

Phytopathology ◽

10.1094/phyto-98-11-1205 ◽

2008 ◽

Vol 98 (11) ◽

pp. 1205-1211 ◽

Cited By ~ 6

Author(s):

R. B. Martins ◽

L. A. Maffia ◽

E. S. G. Mizubuti

Keyword(s):

Genetic Variability ◽

Production Systems ◽

Diversity Index ◽

Vegetative Compatibility ◽

Cercospora Leaf Spot ◽

Vegetative Compatibility Groups ◽

Nit Mutants ◽

Geographical Regions ◽

Minas Gerais State ◽

Cercospora Coffeicola

Cercospora leaf spot is a destructive fungal disease that has become a threat to the coffee industry in Brazil. Nevertheless, little is known about populations of its causal agent, Cercospora coffeicola. We evaluated the potential of using nitrogen-nonutilizing (nit) mutants and vegetative compatibility groups (VCGs) to characterize the genetic variability of the C. coffeicola population associated with coffee plantings in Minas Gerais state (MG), Brazil. A total of 90 monosporic isolates were obtained from samples collected according to a hierarchical sampling scheme: (i) state geographical regions (Sul, Mata, and Triângulo), and (ii) production systems (conventional and organic). Nit mutants were obtained and 28 VCGs were identified. The 10 largest VCGs included 72.31% of all isolates, whereas each of the remaining 18 VCGs included 1.54% of the isolates. Isolates of the largest VCGs were found in the three regions sampled. Based on the frequencies of VCGs at each sampled level, we estimated the Shannon diversity index, as well as its richness and evenness components. Genetic variability was high at all hierarchical levels, and a high number of VCGs was found in populations of C. coffeicola associated with both conventional and organic coffee plantings.

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Vegetative Compatibility Groups of Fusarium oxysporum f. sp. lactucae from Lettuce

Plant Disease ◽

10.1094/pd-89-0237 ◽

2005 ◽

Vol 89 (3) ◽

pp. 237-240 ◽

Cited By ~ 23

Author(s):

Matias Pasquali ◽

Flavia Dematheis ◽

Giovanna Gilardi ◽

Maria Lodovica Gullino ◽

Angelo Garibaldi

Keyword(s):

Fusarium Oxysporum ◽

Genetic Relatedness ◽

The United States ◽

Vegetative Compatibility ◽

Vegetative Compatibility Group ◽

Vegetative Compatibility Groups ◽

Compatibility Group ◽

Race 1

Fusarium oxysporum f. sp. lactucae, the causal agent of Fusarium wilt of lettuce, has been reported in three continents in the last 10 years. Forty-seven isolates obtained from infected plants and seed in Italy, the United States, Japan, and Taiwan were evaluated for pathogenicity and vegetative compatibility. Chlorate-resistant, nitrate-nonutilizing mutants were used to determine genetic relatedness among isolates from different locations. Using the vegetative compatibility group (VCG) approach, all Italian and American isolates, type 2 Taiwanese isolates, and a Japanese race 1 were assigned to the major VCG 0300. Taiwanese isolates type 1 were assigned to VCG 0301. The hypothesis that propagules of Fusarium oxysporum f. sp. lactucae that caused epidemics on lettuce in 2001-02 in Italian fields might have spread via import and use of contaminated seeds is discussed.

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