• The Plant Pathology Journal
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• v.27 no.2
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• pp.116-119
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• 2011

Pyrenophora graminea, the causal agent of leaf stripe disease, is an economically important pathogen of barley found worldwide. Forty-four isolates of diverse geographical origin within Syria were grouped into vegetative compatibility groups (VCGs) by demonstrating heterokaryosis by complementation tests using nitrate nonutilizing (nit) mutants. All isolates were grouped into three VCGs-1-A, 1-B and 1-C. No self-incompatibility was observed in any of the isolates tested. VCG 1-A was the most common group within growing regions in Syria and proved to be the most virulent of the VCGs identified. These data indicate that the level of virulence in P. graminea is related to VCG.

• The Plant Pathology Journal
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• v.27 no.3
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• pp.280-284
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• 2011

Fusarium wilt of banana caused by Fusarium oxysporum f. sp. cubense is widespread in Indonesia. However, the distribution of tropical race 4 strains has not been well studied. Thirty nine isolates of F. oxysporum f. sp. cubense were collected from Java and 7 isolates were from Sumatera, Bangka, and Kalimantan. All isolates produced volatile odor when grown on steamed rice. These isolates were further tested for their vegetative compatibility with nitM testers of 20 reported vegetative compatibility groups representing strains that belong to race 1, 2, and 4. Three isolates formed heterokaryons with nitM testers belong to race 1, 11 isolates with race 4, and the rest did not form heterokaryons with all nitM testers used. F. oxysporum f. sp. cubense tropical race 4 specific primer pair was used to amplify a 1400 bp fragment of tropical race 4 DNA. Seven isolates (Bnt2, Mln1, Srg1, Bgl3, Bgl6, Lmp1, and Kjg1) produced the 1400 bp amplification product were therefore tropical race 4.

• The Plant Pathology Journal
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• v.17 no.5
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• pp.276-280
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• 2001

Fusarium isolates of Gibberella fujikuroi species complex were obtained from sorghum grown in five provinces of Korea in 1996 and 1997. These isolates were characterized based on their mating behavior, mycotoxin production, and vegetative compatibility. Only three mating populations (A, D, and F) were recovered from a total of 155 isolates examined. The relative frequency of the mating populations was significantly different: F was predominant (80%), while D and A were observed at low frequencies of 9% and 3%, respectively. Female fertile isolates were more common within F (44 our of 124) than D (2 out of 14), while none of the five A isolates were female fertile. The inbreeding effective population sizes ($\textrm{N}_e$)for mating type and male/hermaphrodite ratios in mating populations A and D produced significant amounts of fumonisins, while F isolates produced none or only traces of fumonisin B$_1$. In contrast. F isolates produced higher amounts of moniliformin (average of 3,820 ppm) than A and D isolates (averages of 77 and 1,819 ppm, respectively). Fifty-one isolates were tested for vegetative compatibility using nitrogen non-utilization mutants of each isolate, and 44 vegetative compatibility groups (VCGs) were identified. A single VC type (VC1) was found in all of the five A isolates examined. Six of the D isolates examined consisted of three VC types: two for VC2, two for VC3, and the rest for VC4. All of the F isolates tested were incompatible in every combination and , thus, each constituted a unique VCG.

• The Plant Pathology Journal
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• v.26 no.3
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• pp.216-222
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• 2010

Fusarium proliferatum is the causal agent of stalk and root rot disease of maize, foot rot disease of rice, basal and root rot disease of onion and knife cut disease of sugarcane in Iran. In recent years, incidence and severity of these diseases have been increased in Iran. Fifty seven F. proliferatum single-spore isolates collected from diseased maize, rice, onion and sugarcane plants at different areas were used to study genetic diversity by determination of vegetative compatibility groups (VCGs). Chlorate-resistant nitrate non-utilizing (nit) mutants were recovered from selected isolates of F. proliferatum and used in complementation tests. All isolates in which both nit1 and NitM (or nit3) mutants were recovered, demonstrated self-compatibility. Vegetative compatibility tests by pairing nit mutants identified 30 VCGs among 57 isolates. Twenty-three isolates belonged to singlemember VCGs and the remaining 34 isolates, belonged to other seven multimember VCGs. Segregation of F. proliferatum isolates obtained from various area and host plants into different VCGs in Iran is reported for the first time. In this study, none of isolates obtained from rice complemented with any other isolates from onion and sugarcane and, non complementation occurred between onion and sugarcane isolates. Also, only one complementation occurred between one isolate of maize and one isolate of sugarcane and rice. Thus, a correlation between VCGs grouping and host preferences was founded. It is concluded that natural populations of F. proliferatum in Iran are probably genetically divergent and include isolates representing a potential risk for disease development.

• Korean Journal Plant Pathology
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• v.11 no.4
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• pp.330-337
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• 1995

Forty-six isolates of Fusarium oxysporum collected from infected tomato plants and soils in greenhouses in Sedo, Chungnam and Angang, Kyeongbuk and 8 isolates of F. oxysporum f. sp. lycopersici from Japan and USA were used to determine vegetative compatibility groups (VCGs). Vegetative comaptibility was assessed on the basis of heterokaryon formation among nitrate nonutilizing mutants. All Korean isolates of F. oxysporum f. sp. lycopersici used in this study belonged to the same type of VCG (003) regardless of their geographic origin, cultivar and race, but they were incompatible with the foreign isolates of VCG 0030, 0031, 0032 and 0033. Based on the results, the Korean isolates of F. oxysporum f. sp. lycopersici were classified as a new VCG 003.

• The Plant Pathology Journal
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• v.21 no.3
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• pp.214-220
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• 2005

Vegetative compatibility groups (VCGs) of Fusarium oxysporum f. sp. radicis-lycopersici isolates collected from tomatoes in Korea were analyzed to determine the genetic characteristics and compared to those of foreign isolates. In comparison of VCG specificity with foreign VCG subgroup testers, Korean isolates were revealed to be VCG 0094 and to be similar to those of Israel and Florida, USA having a 'Universal' property. Results of this study will contribute the effective control of disease through precise estimation of fungal damage, the prediction of new pathogenic isolates appearance, and the movement of foreign pathogens.

• The Korean Journal of Mycology
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• v.22 no.4
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• pp.343-349
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• 1994

One hundred and two virulent(V) strains of Cryphonectria parasitica were isolated from the cankers of American chestnut (Castanea dentata) trees in western Massachusetts, USA. The diversity of vegetative compatibility groups (VCGs) of C. parasitica was investigated. One hundred and two strains represented 54 VCGs; 38 VCGs had only one strain each, 6 VCGs had 2 strains each, and 10 most common VCGs had 52 strains. Great diversity in VCGs may due to the increasing numbers of VCGs with time since the pathogen has been in Massachusetts for 80 years. Ten vegetative compatibility representative strains were selected from the 10 most common VCGs and converted to hypovirulent (H) strains through the pairing and hyphal anastomosis of H strains (4 strains with French dsRNA elements and 17 strains with Italian dsRNA elements). All of the 10 representative strains were converted to H strains by at least more than one of the H strains.

• The Plant Pathology Journal
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• v.17 no.6
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• pp.377.3-377
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• 2001

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2000.10a
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• pp.30.2-30
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• 2000

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1999.10a
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• pp.47.2-47
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• 1999