Pathogenicity, Host Range and Influence of Temperature, Humidity and pH Levels on the Growth of Fusarium oxysporum f.sp. lentis

2021 ◽  
Author(s):  
Manju Kumari ◽  
Om Prakash Sharma ◽  
B.D.S. Nathawat
Keyword(s):  
Relative Humidity ◽  
Fusarium Oxysporum ◽  
Host Range ◽  
Disease Incidence ◽  
Pathogenicity Test ◽  
Potential Threat ◽  
Influence Of Temperature ◽  
Soil Inoculation ◽  
Inoculation Techniques

Background: Lentil is a vital nutritional source of protein in several parts of the world including India. The crop is susceptible to wilt which is a devastating soil-borne disease induced by the fungus Fusarium oxysporum f. sp. lentis. Insight of the potential threat Fusarium wilt can pose to lentils, a present study done on pathogenicity, host range and influence of temperature, humidity and pH levels on the growth of F. oxysporum f. sp. lentis.Methods: Ten isolates FOL-01 to FOL-10 of F. oxysporum f. sp. lentis (Fol) were isolated from wilted lentil plants that collected from different major lentil growing parts of Rajasthan. During 2017-18 a pathogenicity test was tested in pot house condition by seed and soil inoculation techniques for all isolates and epidomological factors evaluated in vitro conditions.Result: Results indicated that the Fol isolates represent a single race but differ in their aggressiveness on the susceptible cultivar L9-12. Pathogenicity test revealed clearly that Fol was associated with wilt symptoms and were pathogenic to lentil plants. A maximum percent disease incidence of 70.00 was showed by isolate FOL-02 in soil inoculation technique. In the morphological and cultural characterization, all the ten isolates showed various character in conidial frequency, colony color and growth pattern. Twenty plant species were tested to know the host range of Fol, out of these lentil, chickpea and pea show positive reaction with the pathogen. The influence of temperature, relative humidity and pH on the growth and sporulation of Fol was studied under in vitro conditions. Maximum mycelial growth and sporulation of the Fol were observed at 30°C, 6.0 pH and 60% relative humidity.

scholarly journals Role of Biocontrol Agents in Management of Corm Rot of Saffron Caused by Fusarium oxysporum

Agronomy ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1398
Author(s):  
Vishal Gupta ◽  
Krishna Kumar ◽  
Kausar Fatima ◽  
Vijay Kumar Razdan ◽  
Bhagwati Charan Sharma ◽  
...  
Keyword(s):  
Fusarium Oxysporum ◽  
Growth Promotion ◽  
Disease Incidence ◽  
Biocontrol Agents ◽  
Crocus Sativus ◽  
First Year ◽  
Dual Culture ◽  
Maximum Reduction

Saffron (Crocus sativus L.) is considered as one of the most expensive spices. Fusarium corm rot of saffron, caused by Fusarium oxysporum, is known to cause severe yield losses worldwide. In the present study, efficacy of biocontrol agents (Trichoderma asperellum, Pseudomonas fluorescens, Pseudomonas aeruginosa, Pseudomonas putida, Bacillus stratosphericus, Bacillus pumilus, and Bacillus subtilis) along with a chemical fungicide, carbendazim, was evaluated for managing the corm rot of saffron. Under in vitro conditions, using dual culture and poison food techniques on potato dextrose agar, T. asperellum and carbendazim significantly reduced the mycelial growth of the pathogen F. oxysporum, with the inhibition of 62.76 and 60.27%, respectively, compared with control. Under field conditions, dipping of saffron corms in carbendazim and T. asperellum exhibited maximum reduction of 82.77 and 77.84%, respectively, in the disease incidence, during the first year of experiment. However, during the second year, maximum reduction in the incidence of corm rot (68.63%) was recorded with the T. asperellum. Moreover, the population density of F. oxysporum was also significantly reduced by 60 and 80.19% while using T. asperellum after 75 and 260 days of sowing of saffron corms, compared to its population before planting of corms. In case of growth promotion traits, such as sprouting and flowering, biocontrol treatments reduced the number of days (average) of sprouting and flower emergence after sowing, compared to control.

scholarly journals Cultural Characteristics, Virulence and In-vitro Chemical Control of Fusarium oxysporum f. sp. phaseoli of Bush bean (Phaseolus vulgaris L.)

2014 ◽  
Vol 12 (1) ◽  
pp. 103-110 ◽  
Author(s):  
SS Siddique ◽  
MKA Bhuiyan ◽  
R Momotaz ◽  
GMM Bari ◽  
MH Rahman
Keyword(s):  
Fusarium Oxysporum ◽  
Root Rot ◽  
Growth Stages ◽  
Pathogenicity Test ◽  
Flowering Stage ◽  
Pathology Laboratory ◽  
Leaf Yellowing ◽  
Bush Bean ◽  
Different Growth Stages

An experiment was conducted at Microbiology Laboratory of Plant Pathology Department, Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU) during 2007 to determine the virulence and variation in symptom development by Fusarium oxysporum f. sp. phaseoli isolates at different growth stages such as emergence and early vegetative stage, branching and rapid vegetative growth stage and early flowering stage of Bush bean, and in-vitro control of the pathogen with the selected fungicides. Eight isolates of this pathogen were collected from different pathology laboratory of BARI, BAU and BSMRAU. IS3 isolate collected from Bushbean seeds were found most virulent in pathogenicity test such as pre-emergence mortality, root rot, root lesion, leaf yellowing and wilting when this isolate was inoculated at different growth stages of bush bean. Four fungicides such as Vitavax, Rovral, Cupravit and Aimcozim were evaluated invitro to test the efficacy against isolate IS3. Aimcozim at different concentration (50-400 ppm) was found most effective in in-vitro evaluation. DOI: http://dx.doi.org/10.3329/agric.v12i1.19865 The Agriculturists 2014; 12(1) 103-110

Effects of Streptomyces corchorusii, Streptomyces mutabilis, pendimethalin, and metribuzin on the control of bacterial and Fusarium wilt of tomato

1996 ◽  
Vol 74 (7) ◽  
pp. 1016-1022 ◽  
Author(s):  
Abd El-Raheem R. El-Shanshoury ◽  
Soad M. Abu El-Sououd ◽  
Omima A. Awadalla ◽  
Nabila B. El-Bandy
Keyword(s):  
Fusarium Oxysporum ◽  
Culture Media ◽  
Disease Incidence ◽  
Inhibitory Effects ◽  
Pseudomonas Solanacearum ◽  
Negative Effects ◽  
Streptomyces Spp ◽  
Antagonistic Streptomyces

Two Streptomyces spp. and two herbicides were used to control the pathogens of tomato wilt disease in vitro and in vivo. In vitro studies showed inhibitory effects of Streptomyces corchorusii against Fusarium oxysporum f.sp. lycopersici (Sacc.) and inhibitory effects of Streptomyces mutabilis against Pseudomonas solanacearum. In cultures amended with pendimethalin or metribuzin, the growths of P. solanacearum and F. oxysporum were inhibited. The degree of growth inhibition was proportional to the herbicide concentration, with pendimethalin being more effective than metribuzin, and maximum inhibition was at 2.0 × 10−3 M. The growth of S. corchorusii and S. mutabilis was slightly inhibited or enhanced by the herbicides. Supplementation of the herbicides to culture media of the antagonistic Streptomyces spp. increased their inhibitory effects against P. solanacearum and F. oxysporum that were proportional to the herbicide concentrations. Soaking seeds of tomato in the herbicides prior to sowing in sterilized and raw soils and applying S. corchorusii and (or) S. mutabilis to the soils artificially infested with P. solanacearum and (or) F. oxysporum f.sp. lycopersici (Sacc.) 40 days after transplanting revealed significant interactions that gave better control of wilt than either applied alone. The combination of antagonistic Streptomyces spp. was more effective with pendimethalin than with metribuzin and in nonsterilized soil than in sterilized soil. The combination of pendimethalin with S. corchorusii, S. mutabilis, or S. corchorusii plus S. mutabilis was more effective than the single treatment with microbial antagonists or the herbicide against F. oxysporum, P. solanacearum, and Pseudomonas plus Fusarium, respectively. In both soils, the combination of microbial antagonists with pendimethalin was most effective at 2.0 × 10−3 M, disease incidence being reduced to zero and the percent colonization of either pathogen being the lowest. The results also revealed that these combinations minimized the negative effects of the pathogens on tomato growth. This work demonstrates that two compatible control agents, biological and chemical, can be combined to give additional control of a plant pathogen. Keywords: Streptomyces spp., herbicides, Pseudomonas solanacearum, Fusarium oxysporum f.sp. lycopersici (Sacc.), wilt, Lycopersicon esculentum Mill.

scholarly journals POTENTIAL OF PLANT EXTRACTS AND FUNGICIDES FOR MANAGING FUSARIUM OXYSPORUM F. SPLYCOPERSICI

2018 ◽  
Vol 30 (1) ◽  
pp. 75 ◽  
Author(s):  
Gul B. Poussio ◽  
Manzoor A. Abro ◽  
Jamal U. D. Hajano ◽  
Muhammad I. Khaskheli ◽  
Khalid I. Rajput ◽  
...  
Keyword(s):  
Fusarium Oxysporum ◽  
Mycelial Growth ◽  
Disease Incidence ◽  
Block Design ◽  
Fungal Growth ◽  
Tomato Crop ◽  
Randomized Block Design ◽  
Sindh Province ◽  
Causal Fungus

Fusarium oxysporum f.sp. lycopersici (FOL) is a highly destructive fungal pathogen of tomato crop causing wilt disease which may reduce 10 to 90% yield. In Pakistan, tomato is widely grown in Sindh province, major territories are district Hyderabad, Tando Allahyar and Mirpurkhas. Thus, surveys of these territories were conducted to record intensity of the disease and confirm etiology. Furthermore, potential of different botanical pesticides and commercially available fungicides were tested to inhibit mycelial growth of the causal fungus. The experiment was laid down with complete randomized block design with three replications. The results showed that the disease was occurring in all locations with the range of 8-47 % incidence. F. oxysporum f.sp. lycopersici was predominantly isolated from the collected disease sample during survey and pathogenic nature of the fungus was tested on the tomato Golo variety through soil drenching method. The disease incidence of 30 and 42 % (72 % as total) was recorded in inoculated tomato plants at 20 and 40 DAI, respectively. Maximum (67 %) inhibition of the fungal growth was found by neem seed extracts at higher dose of 8 % concentration followed by 63 % with neem seeds and Eucalyptus at 6 and 8 %, respectively. Alternatively, the Nativo 75 WG fungicide was found most effective in reducing the redial mycelial growth of target fungus followed by Topsin-M at 1000 ppm where as Aliette and Melodedue fungicides were found least effective under in-vitro conditions.

scholarly journals First Report of Fusarium Wilt of Lavandula pubescens Caused by Fusarium oxysporum in Saudi Arabia

Plant Disease ◽  
2010 ◽  
Vol 94 (9) ◽  
pp. 1163-1163 ◽  
Author(s):  
K. Perveen ◽  
N. Bokhari
Keyword(s):  
Saudi Arabia ◽  
Fusarium Oxysporum ◽  
Vascular Tissue ◽  
Agricultural Research ◽  
Indian Agricultural Research Institute ◽  
Pathogenicity Test ◽  
Conidial Suspension ◽  
Potential Threat ◽  
King Saud University ◽  
First Report

In November 2008, a wilt of lavender (Lavandula pubescens) seedlings was observed in the greenhouse at King Saud University, Riyadh, Saudi Arabia. Affected seedlings were wilted and the root system was poorly developed. Diseased stems developed a dark coloration that extended down to the roots. Vascular tissue of the affected seedlings appeared red or brown. Isolations consistently yielded a fungus growing from the discolored stem tissue when placed on potato dextrose agar. The macroscopic characteristics of the colony, as well as microscopic structures, were used to identify the fungus as Fusarium oxysporum (2). Oval to elliptical microconidia without septa and originating from short phialides were used to distinguish the species from F. solani (1). The fungus was authenticated by the ITCC (Indian Type Collection Centre), Indian Agricultural Research Institute, New Delhi, India, and given I.D. No. 7532.09. For conducting further experiments, healthy seedlings of L. pubescens were obtained from the botanical garden of the King Saud University and grown in steam-sterilized soil. Healthy seedlings of lavender were inoculated using a root-dip method with a conidial suspension (1 × 107 CFU/ml) of one strain of F. oxysporum obtained from infected plants. Inoculated seedlings were then transplanted into steam-sterilized soil. Plants inoculated with sterilized water (1 ml per plant) served as control treatments. Wilt symptoms and vascular discoloration in the roots and crown developed within 20 days on all plants inoculated with the pathogen, while control plants remained asymptomatic. F. oxysporum was consistently reisolated from symptomatic plants. The pathogenicity test was conducted twice. To our knowledge, this is the first report of F. oxysporum on L. pubescens in Saudi Arabia or elsewhere in the world, and this newly identified disease may be a potential threat to commercial production of lavender. References: (1) J. F. Leslie and B. A. Summerell. Page 212 in: The Fusarium Laboratory Manual. Blackwell Publishing Professional, Hoboken, NJ, 2006. (2) P. C. Nelson et al. Clin. Microbiol. Rev. 7:479, 1994.

scholarly journals Fusarium oxysporum (F221-B) as biocontrol agent against plant pathogenic fungi in vitro and in hydroponics

2017 ◽  
Vol 53 (No. 2) ◽  
pp. 85-95 ◽  
Author(s):  
Thongkamngam Titi ◽  
Jaenaksorn Tanimnun
Keyword(s):  
Fusarium Oxysporum ◽  
Fungal Pathogens ◽  
Biocontrol Agent ◽  
Disease Incidence ◽  
Pathogenic Fungi ◽  
Curvularia Lunata ◽  
Plant Growth Promoting ◽  
Healthy Control ◽  
Further Development

Efficacy of non-pathogenic Fusarium oxysporum (F221-B) was assessed as a possible biocontrol agent against fungal pathogens, namely Curvularia lunata (C11, C12), F. semitectum (F113), F. oxysporum f.sp. lactucae (F221-R, F442-G), Rhizoctonia solani (R11, R12), Rhizoctonia sp. (R111, R112, R113) in vitro, while F221-B showed a moderate ability to inhibit the mycelial growth of tested fungi about 36–56%. Then, F221-B was further evaluated for its ability of controlling lettuce root rot and wilt caused by F442-G in hydroponics. It was revealed that F221-B reduced disease incidence and severity about 60–80% compared to the inoculated control and significantly promoted the growth of 3 lettuce varieties. Interestingly, using only F221-B gave the significantly highest fresh weight (twice over the healthy control). Conclusively, this study provides an important suggestion for further development of F221-B since it showed the ability of biocontrol agent and plant growth promoting fungus.

scholarly journals Integrated management of the Fusarium vascular wilt disease of Cucurbita pepo in Iraq

2019 ◽  
Vol 23 (1) ◽  
pp. 40
Author(s):  
Safaa N. Hussein
Keyword(s):  
Cucurbita Pepo ◽  
Disease Incidence ◽  
Dry Weight ◽  
Negative Control ◽  
Wilt Disease ◽  
Pathogenicity Test ◽  
Vascular Wilt ◽  
Universal Primer ◽  
Vascular Wilt Disease

Fusarium vascular wilt disease is one of the most harmful disease that affected broad range of plant species including zucchini (Cucurbita pepo). The objective of the research was to investigate the presence of the phytopathogenic gungus Fusarium oxysporum the causal agent of the disease in zucchini fields. Forty five isolates of F. oxysporum were isolated from four locations in province of Dyala during 2014-2015. Isolate Foq9 was most virulent in the pathogenicity test in vitro. Twenty nine isolates of them amplified their DNA positively with the universal primer of F. oxysporum in the polymerase chain reaction technique (PCR). In vitro significant suppression efficiency were observed of the fungicides Topsin M 70 WP (Tm) and Tecto 500 SC (Tc) and two botanical extract solution extracted from Garlic (Gr) and Ginger (Gn) against the pathogen on the potato sucrose agar (PSA). In greenhouse experiments all of the agents decreased the percentage of disease incidence and severity significantly, while the tetra-inoculum (Tm+Tc+Gr+Gn) was superior which exhibited 0% disease incidence and severity compared to the negative control which was 95%, 79% respectively, also the combined application of the botanical extracts (Gr+Gn) reduced the disease incidence and severity significantly. All of the treatment increased plant growth criteria represented by dry weight of the plant compared to the control.

scholarly journals Prevalence of Fusarium Wilt Disease of Cucumber (Cucumis sativus Linn) in Peninsular Malaysia Caused by Fusarium oxysporum and F. solani

2020 ◽  
Vol 31 (3) ◽  
pp. 29-45
Author(s):  
Hazirah Mohd Din ◽  
Osamah Rashed ◽  
Khairulmazmi Ahmad
Keyword(s):  
Fusarium Oxysporum ◽  
Fusarium Wilt ◽  
Disease Incidence ◽  
Infected Plant ◽  
Peninsular Malaysia ◽  
Disease Prevalence ◽  
Wilt Disease ◽  
Infested Soil ◽  
Pathogenicity Test ◽  
Fusarium Wilt Disease

Fusarium wilt disease is one of the most problematic and destructive disease in cucumber production. The causative agents are Fusarium oxysporum and F. solani. These pathogens are soil borne and transmitted through infested soil and water. A field survey was conducted to study the disease prevalence in the major growing areas of cucumber in Peninsular Malaysia. Field study revealed that the disease was highly prevalence in the field with the disease incidence was in the range of 10%–60%. The morphological properties of F. oxysporum are microconidia (3.8–15.7 μm × 2.9–4.9 μm), macroconidia (14.8–38.5 μm × 2.4–5.7 μm) and number of septate was 1–4. While for F. solani are microconidia (3.39–14.63 μm × 2.36–4.44 μm), macroconidia (7.22–50.46 μm × 2.43–6.14 μm) and number of septate was 1–5. Based on molecular identification had confirmed that the disease is caused by F. oxysporum and F. solani with similarity index of 99%–100% based on internal transcribed spacer (ITS) gene sequences. The pathogenicity test showed that the symptoms of Fusarium wilt disease was firstly appeared as yellowing of old leaves. Progressively, the infected plant will be wilted and finally died. The outputs of this study are highly important to establish an effective disease management programme to reduce disease prevalence and yield loss in the field.

scholarly journals First Report of Fusarium Wilt of Paper Flower (Bougainvillea glabra) Caused by Fusarium oxysporum in Italy

Plant Disease ◽  
2010 ◽  
Vol 94 (4) ◽  
pp. 483-483 ◽  
Author(s):  
G. Polizzi ◽  
D. Aiello ◽  
V. Guarnaccia ◽  
A. Vitale ◽  
G. Perrone ◽  
...  
Keyword(s):  
Fusarium Oxysporum ◽  
Fusarium Wilt ◽  
Disease Incidence ◽  
Elongation Factor ◽  
Gene Sequences ◽  
Single Spore ◽  
Potential Threat ◽  
First Report ◽  
Potted Plants ◽  
Bougainvillea Glabra

Paper flower (Bougainvillea glabra Choisy), native to Brazil, is the most widely and intensively cultivated species of bougainvillea as a potted plant in Sicily (Italy). During 2008 and 2009, a wilting of vegetatively produced B. glabra cv. Sanderiana was observed in several nurseries in eastern Sicily (Catania and Messina provinces). Disease incidence was higher (~10 to 30%) in the tree-shaped potted plants (standards). Occasionally, wilting was detected on plants that were not tree shaped. Internally, symptomatic plants showed conspicuous vascular orange discoloration from the crown to the canopy. Diseased crown and stem tissues were surface disinfested for 30 s in 1% NaOCl, rinsed in sterile water, plated on potato dextrose agar (PDA) amended with 100 mg/liter of streptomycin sulfate, and incubated at 25°C. A Fusarium sp. was consistently isolated from affected plant tissue. Colonies with light purple or purple mycelia and violet reverse colony colors developed after 10 days. On carnation leaf agar, single-spore isolates produced microconidia in false heads on short monophialides, macroconidia that were 3-septate with a pedicellate base, and solitary and double-celled or aggregate chlamydospores. A PCR assay was conducted on two representative strains (DISTEF-BGS1 and DISTEF-BGS2) by analyzing sequences of the parzial translation elongation factor alpha gene (TEF-1α) and CaM gene (coding calmodulin protein). The primers used are previously used by O'Donnell et al. (1,2). Calmodulin sequences of BGS1 and BGS2 strains (GenBank Nos. FN645740 and FN645741, respectively) exhibited 99% homology with Fusarium oxysporum strain ITEM 2367 (GenBank No. AJ560774), and have homology of 99.6% between them. TEF-1 gene sequences of BGS1 (GenBank No. FN645739) exhibited an identity of 100% to F. oxysporum f. sp. lycopersici MUCL 22544 GenBank No. EF056785.1) and TEF-1α gene sequences of BGS2 (GenBank No. FN655742) exhibited an identity of 100% to F. oxysporum strain NRRL 45954 (GenBank No. FJ985431.1), whereas the homology between the two strains is 98.5%. Both PCR approaches established the identity of the isolates to the F. oxysporum Schlechtend:Fr (1,2). Pathogenicity tests were performed by placing 1-cm2 plugs of PDA from 10-day-old mycelial cultures near the crown on 40 potted, healthy, 6-month-old cuttings of paper flower. Twenty plants for each isolate were used. The same number of plants served as noninoculated controls. All plants were enclosed for 5 days in plastic bags and placed in a growth chamber at 24 ± 1°C. Plants were then moved to a greenhouse where temperatures ranged from 24 to 26°C. Symptoms identical to those observed in nurseries developed 1 month after inoculation with both strains. Crown and stem orange discoloration was detected in all inoculated plants after 2 months. Control plants remained symptomless. F. oxysporum was consistently reisolated from symptomatic tissues and identified as previously described. To our knowledge, F. oxysporum was previously reported on paper flower in Ghana (3). However, this is the first demonstration of the pathogenicity of F. oxysporum on paper flower and it is the first report in Europe of the disease. The presence of Fusarium wilt in Sicily is a potential threat to paper flower production in nurseries. References: (1) K. O'Donnell et al. Proc. Natl. Acad. Sci. USA 95:2044, 1998. (2) K. O'Donnell et al. Mycoscience 41:61, 2000. (3) P. Spaulding. USDA Agric. Handb. 197:1, 1961.

scholarly journals First Report of Powdery Mildew Caused by Erysiphe buhrii on Gypsophila paniculata in Korea

Plant Disease ◽  
2014 ◽  
Vol 98 (7) ◽  
pp. 1013-1013 ◽  
Author(s):  
I. Y. Choi ◽  
B. S. Kim ◽  
S. E. Cho ◽  
J. H. Park ◽  
H. D. Shin
Keyword(s):  
Powdery Mildew ◽  
Host Range ◽  
Disease Incidence ◽  
Width Ratio ◽  
Korean Isolate ◽  
Pathogenicity Test ◽  
Cut Flower ◽  
Voucher Specimen ◽  
First Report ◽  
Gypsophila Paniculata

Gypsophila paniculata L. (baby's breath, family Caryophyllaceae), native to Central and Eastern Europe, is commonly cultivated as a commercial cut flower crop in greenhouses in Korea. Since 2011, baby's breath cv. Cassiopeia has been observed affected by a powdery mildew with nearly 100% disease incidence at the stage of harvesting in Iksan City. Powdery mildew colonies first appeared as thin white patches on stems and both sides of the leaves. As disease progressed, plants were covered with dense masses of spores, followed by senescence and reduction of quality of cut flowers. A voucher specimen was deposited in the Korea University Herbarium (Accession KUS-F27313). Appressoria were well-developed, multilobed or moderately lobed, and single or opposite in pairs. Conidiophores were straight, 95 to 150 × 7 to 10 μm, and composed of 3 to 4 cells. Foot-cells were cylindric or slightly sinuous at the base and 37 to 53 μm long. Singly produced conidia were cylindrical to oblong-elliptical, 35 to 56 × 12.5 to 18 μm with a length/width ratio of 2.1 to 3.6, devoid of fibrosin bodies, and with angular/rectangular wrinkling of outer walls. Germ tubes were in the perihilar position on conidia, and ended with lobed appressoria. No chasmothecia were found. These structures are typical of the Pseudoidium anamorph of the genus Erysiphe. Specific measurements and host range were consistent with those of E. buhrii U. Braun (2). To confirm identification, the complete internal transcribed spacer (ITS) region of rDNA of isolate KUS-F27313 was amplified with primers ITS1/ITS4, and sequenced directly. The resulting 725-bp sequence was deposited in GenBank (KJ530705). A GenBank BLAST search of the Korean isolate showed 99% similarity with E. buhrii on Acanthophyllum sp. (Caryophyllaceae) from Iran (AB128924). Pathogenicity was confirmed through inoculation by gently dusting conidia onto leaves of five healthy, potted baby's breath cv. Cassiopeia. Five non-inoculated plants served as controls. Inoculated plants were isolated from non-inoculated plants in separate rooms in a greenhouse at 25 ± 2°C. Inoculated plants developed signs and symptoms after 7 days, whereas the control plants remained symptomless. The fungus present on the inoculated plants was identical morphologically to that originally observed on diseased plants. Pathogenicity test was repeated twice. The powdery mildew disease caused by E. buhrii on baby's breath has been recorded in the former Soviet Union (Armenia, Kazakhstan, Ukraine), Romania, Turkey, Iran, Mongolia, and Argentina (1,3). Also, a fungus occurring on baby's breath was recorded as Oidium sp. from Japan (4). To our knowledge, this is the first report of powdery mildew caused by E. buhrii on baby's breath in Korea. Powdery mildew infections pose a serious threat to production of this cut flower crop. References: (1) K. Amano. Host Range and Geographical Distribution of the Powdery Mildew Fungi. Japan Scientific Societies Press, Tokyo, 1986. (2) U. Braun and R. T. A. Cook. Taxonomic Manual of the Erysiphales (Powdery Mildews), CBS Biodiversity Series No. 11. CBS, Utrecht, 2012. (3) D. F. Farr and A. Y. Rossman. Fungal Databases. Syst. Mycol. Microbiol. Lab., Online publication, ARS, USDA, Retrieved February 18, 2014. (4) M. Satou et al. Ann. Phytopathol. Soc. Jpn. 62:541, 1996.

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