The studies on ash dying (Fraxinus excelsior L.) in the Włoszczowa Forest Unit stands

The studies were carried out in the Włoszczowa Forest Unit, in 9 ash stands differing in respect of age, origin (natural, artificial), site and in the nursery on 3 quarters differing due to a silvicultural method (transplanted and not transplanted) and seedlings age. In each stand an analysis of disease symptoms was carried out on 100 trees (2 - 20 years old stands) or 50 trees (21 - 80 years old stands) growing side by side in central part of the stand, while in the nursery in each block 200 seedlings were analyzed (4 sectors with 50 seedlings each). From the infected seedlings and trees 120 fragments of dead branches, living branches with cankers, and dead roots were taken. Identification of fungi was made on the basis of fructification and over 300 isolations of fungi on malt agar medium. The most frequent disease symptoms in ash stands were: the dead top (34.7% trees), the dying of whole branches (83.5%), the dying of the top of branches (20.1%), the occurrence of healed (36.0%) and unhealed cankers (18.9%) and the slime flux (23.7%) on the trunk, also the chlorosis of leaves (7.5%) and their atrophy (11.2%). Most of the types of disease symptoms appeared irrespectively of the tree age, origin and site, sometimes showing only a difference in the frequency of occurrence. On the seedlings in the nursery the shoot discolouration, healed and unhealed cankers on shoots and necrosis of a part of leaves were recorded most frequently. Disease symptoms occurred more frequently on 4-year-old seedlings in comparison with 3-year-old. In respect of transplanted seedlings the leaves dying was more frequent. Within cankers and on dead tops of shoots the most frequent were: Alternaria alternata, Chalara sp., Cytospora ambiens, Diplodia mutila, Fusarium lateritium, Gloeosporidiella turgida, Phomopsis controversa and Phomopsis scobina. In sparsely found dead roots of living trees appeared mostly: Cryptosporiopsis radicicola, Cylindrocarpon destructans and Phialocephala sp.

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First Report of Umbel Browning and Stem Necrosis Caused by Diaporthe angelicae on Carrot in France

Plant Disease ◽

10.1094/pdis-06-13-0673-pdn ◽

2014 ◽

Vol 98 (3) ◽

pp. 421-421 ◽

Cited By ~ 3

Author(s):

L. Ménard ◽

P. E. Brandeis ◽

P. Simoneau ◽

P. Poupard ◽

I. Sérandat ◽

...

Keyword(s):

Seed Production ◽

White Light ◽

Agar Medium ◽

Malt Agar ◽

Universal Primers ◽

Conidial Suspension ◽

First Report ◽

Daucus Carota L ◽

Cropping Seasons ◽

Production Areas

In 2011, carrot (Daucus carota L.) seed production occurred on 2,900 ha, which accounts for approximately 25% of the area devoted to the production of vegetable fine seeds. Since 2007, symptoms of umbel browning have been regularly observed in carrot production areas located in the central region. Initially, triangular necrotic lesions appeared on carrot umbels that later spread to the entire umbels and often progressed to the stems. Diseased umbels became dried prematurely, compromising seed development. The loss in seed production was estimated at approximately 8% of the harvested carrot umbels during the cropping seasons of spring and summer 2007 and 2008 in France. In collaboration with seed companies, diseased carrot stems were collected from seven fields of seed production (eight plants per field) and a fungus was isolated from the tissue. The cultures were grown on malt (2%) agar (1.5%) medium and incubated for 2 weeks at 22°C in darkness. Young fungal colonies were white and a brownish green pigmentation developed when the colonies became older. The same color was observed from the top and on the reverse of the colonies. To induce sporulation, isolates were grown on water agar (1.5%) medium in the presence of carrot stem fragments for 1 week at 22°C in darkness, followed by 1 week at 22°C in white light under a 16-h photoperiod. Pycnidia were produced on stem fragments and contained alpha and beta conidia typical of the genus Diaporthe (2). Alternatively, pycnidia were also obtained on malt agar medium after 2 weeks of culture at 25°C in white light under a 12-h photoperiod. The size of alpha and beta conidia was 6.3 ± 0.5 × 2.3 ± 0.4 μm and 23.3 ± 1.8 × 0.9 ± 0.2 μm, respectively (n = 170). In order to confirm the identification at the genus level and determine the species, DNA was extracted from the mycelium of three representative isolates and the ITS regions of the ribosomal DNA were amplified using universal primers (1). The sequences of the amplified products (GenBank Accession Nos. KF240772 to KF240774) were 100% identical with the ITS sequence of a Diaporthe angelicae isolate deposited in the NCBI database (CBS 111592 isolate, KC343027). To confirm pathogenicity, the three isolates of D. angelicae were inoculated on carrot umbels in the greenhouse. A total of nine plants were inoculated (three plants per isolate). Using a micropipette, 10 μl of a conidial suspension containing alpha and beta conidia (105 conidia mL–1) were deposited at the base of the primary umbel and two secondary umbels, which were wounded before inoculation using a scalpel blade. Seven inoculated plants developed triangular, necrotic lesions that were typical umbel browning. D. angelicae was re-isolated on malt agar medium from the inoculated diseased carrot umbels. To our knowledge, this is the first report of D. angelicae in carrot cultivated for seed production in France. The disease resembles the lesions described in the Netherlands in 1951 on carrot inflorescence caused by Phomopsis dauci (3). In future experiments, it would be crucial to precisely determine if D. angelicae could be transmitted to the seeds. References: (1) M. A. Innis et al. PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, CA, 1990. (2) J. M. Santos and A. J. L. Philips. Fungal Divers. 34:111, 2009. (3) J. A. von Arx. Eur. J. Plant Pathol. 57:44, 1951.

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Micromycetes on Pisum sativum var. arvense

Acta Mycologica ◽

10.5586/am.1997.004 ◽

2014 ◽

Vol 32 (1) ◽

pp. 31-39

Author(s):

Joanna Marcinkowska

Keyword(s):

Pisum Sativum ◽

Botrytis Cinerea ◽

Sclerotinia Sclerotiorum ◽

Alternaria Alternata ◽

Agar Medium ◽

Mycosphaerella Pinodes ◽

Stemphylium Botryosum ◽

Number Of Species ◽

Fusarium Poae ◽

The Common

Seeds of 11 Austrian winter pea genotypes, harvested at Radzików (CEP) in 1993 and 1994, were evaluated for fungi occurrence on Coon's agar medium in Petri plates. Number of species isolated depended on the genotype and year of collection. Alternaria alternata, Stemphylium botryosum were found on all the tested samples and Phoma pinodella and Fusarium poae were also common while Botrytis cinerea, Sclerotinia sclerotiorum and Mycosphaerella pinodes appeared to be common only in 1993. Three species occurred only once. The mycoflora was richer in 1993. The common seed inhabitants usually transmitted higher percentage of fungi than species occuring more seldom.

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Fusarium lateritium: A Pathogen of Spurred Anoda (Anoda cristata), Prickly Sida (Sida spinosa), and Velvetleaf (Abutilon theophrasti)

Weed Science ◽

10.1017/s0043174500040170 ◽

1981 ◽

Vol 29 (6) ◽

pp. 629-631 ◽

Cited By ~ 21

Author(s):

H. Lynn Walker

Keyword(s):

Abutilon Theophrasti ◽

Weed Species ◽

Disease Symptoms ◽

Naturally Occurring ◽

Fusarium Lateritium ◽

Hibiscus Trionum ◽

Sida Spinosa ◽

Stem Lesions ◽

Prickly Sida ◽

Anoda Cristata

An isolate ofFusarium lateritium(Nees) emend. Snyder and Hansen was associated with naturally occurring disease of spurred anoda [Anoda cristata(L.) Schlecht.] and prickly sida (Sida spinosaL.) plants. In greenhouse inoculation studies, theFusariumisolate was pathogenic to healthy spurred anoda and prickly sida plants. The disease symptoms were characterized by leaf, stem, and root lesions. The stem lesions enlarged with time and formed cankers that often girdled the stems and killed inoculated plants. In host-range studies, velvetleaf (Abutilon theophrastiMedic.), Venice mallow (Hibiscus trionumL.), okra [Abelmoschus esculentus(L.) Moench], and hollyhock [Althaea rosea(L.) Cav.] were also susceptible to the pathogen. This is the first report of these six species as hosts for this pathogen. Corn (Zea maysL.), cotton (Gossypium hirsutumL. andG. barbadenseL.), soybean [Glycine max(L.) Merr.], and 18 other representative crop and weed species in eight families were resistant to the pathogen.F. lateritiummay be a useful biological herbicide for susceptible malvaceous weeds.

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The effect of Cylindrocarpon destructans on the growth of Eucalyptus regnans seedlings in air-dried and undried forest soil

Australian Journal of Botany ◽

10.1071/bt08124 ◽

2010 ◽

Vol 58 (2) ◽

pp. 133 ◽

Cited By ~ 6

Author(s):

T. M. Iles ◽

D. H. Ashton ◽

K. J. Kelliher ◽

P. J. Keane

Keyword(s):

Root Growth ◽

Forest Soil ◽

Seedling Growth ◽

Frequency Of Occurrence ◽

Root Tips ◽

Eucalyptus Regnans ◽

Cylindrocarpon Destructans ◽

Pot Experiments ◽

Growth Of Seedlings

The growth of Eucalyptus regnans F.Muell. (mountain ash) seedlings is poor in natural forest soil, where purple coloration of the foliage indicates P deficiency and where the fungus Cylindrocarpon destructans (Zinsm.) Scholten is commonly isolated from the roots of the seedlings. When forest soil is air-dried, P acquisiton and growth of seedlings are markedly improved, although the degree of growth stimulation varies considerably at different times, as does the frequency of occurrence of C. destructans on the roots. C. destructans has been implicated as a possible reason for suppressed growth of seedlings in undried natural soil. To find out whether C. destructans contributes to growth inhibition of E. regnans seedlings in undried forest soil, the effect of three isolates of C. destructans on the root growth of E. regnans seedlings was tested in Petri dish experiments in vitro and the effect of C. destructans inoculation on seedling growth both in air-dried and undried forest soil was tested in pot experiments. The frequency of occurrence of C. destructans on the roots varied at different times, and was not consistently higher in undried than in air-dried soil, even though the growth of the seedlings was always poor in undried soil compared with that in air-dried soil. In vitro, C. destructans decreased the root growth significantly and caused blackening of root tips. This effect was removed by adding natural air-dried or undried soil. In pot experiments using undried forest soil, there was no evidence of either direct toxic effect or any other adverse effect on the roots when soil was inoculated with this fungus, even when the growth of the seedlings was reduced to ~1/2 of that in uninoculated undried soil. In air-dried soil, inoculation with the fungus did not significantly reduce seedling growth. Although potentially pathogenic and able to cause blackening of root tips, C. destructans is unlikely to be the main reason for poor seedling growth in undried forest soil. It appears to be antagonistic rather than pathogenic, suppressing seedling growth only under unfavourable conditions, such as in undried soil, possibly by competing for limited nutrients, or by suppressing other beneficial micro-organisms. The results are discussed in the context of field conditions.

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Species biodiversity of microscopic fungi of common reed (Phragmites australis (Cav.) Trin. ex Steud.) in the rush communities of Lake Glinno

Acta Agrobotanica ◽

10.5586/aa.2005.062 ◽

2012 ◽

Vol 58 (2) ◽

pp. 359-368

Author(s):

Kinga Mazurkiewicz-Zapałowicz ◽

Krystyna Janowicz ◽

Maria Wolska ◽

Anna Słodownik

Keyword(s):

Phragmites Australis ◽

Alternaria Alternata ◽

Common Species ◽

Common Reed ◽

Cladosporium Cladosporioides ◽

Fusarium Sambucinum ◽

Microscopic Fungi ◽

Disease Symptoms ◽

Green Material ◽

Mycelia Sterilia

The studies were carried out on common reed (Phragmites australis) growing on the shores of Lake Glinno and forming rush communities of the alliance Phragmition. 10 plants with disease symptoms were gathered from each of five sites. The isolation and marking of pathogens were performed twice from fragments of leaf and blade tissues with disease symptoms. First, directly after collecting the plants incubated in sterile humid chambers and microorganism cultures on CDA and PDA medium, and then phytopathogen and saprotroph species occurring on dried green material were identified for 2-4 months. The occurrence of 31 species of microscopic fungi overall was observed on the leaves, blades and inflorescences of P. australis, including 2 mycelia of Mycelia sterilia. The most frequently occurring species, present at all sites of Phragmites australis are: Alternaria alternata, Cladosporium cladosporioides, C. herbarum, Doratomyces stemonitis and Puccinia phragmitis, P. magnussiana and two mycelia of Mycelia sterilia. The most common species occurring on blades and inside them are: Acremoniella atra, Acremonium alternatum and Fusarium sambucinum. Sporadically, Ustilago grandis was also observed inside blades. Tiny necrotic stains on leaves and blades were caused by the presence of three species of the genus Leptoshaeria: L. culmifraga, L. eustoma and L. fuckelli. The occurrence of the sclerote of Claviceps microcephala was found in inflorescences.

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Mycoflora of seeds of Bellis perennis and Celosia cristata

Acta Mycologica ◽

10.5586/am.1992.005 ◽

2014 ◽

Vol 27 (1) ◽

pp. 41-48

Author(s):

Barbara Łacicowa ◽

Irena Kiecan ◽

Danuta Pięta

Keyword(s):

Alternaria Alternata ◽

Agar Medium ◽

Phoma Exigua ◽

Celosia Cristata

The seeds of Bellis perennis and Celosia cristata were investigated. Agar medium with nutrients was used to isolate the fungi. Alternaria alternata dominated among isolated fungi. The investigation showed that Phoma exigua was more pathogenic to Bellis perennis.

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Fungi colonizing various organs of thyme Thymus vulgaris L. cultivated in the region of Lublin

Acta Agrobotanica ◽

10.5586/aa.2002.018 ◽

2013 ◽

Vol 55 (1) ◽

pp. 185-197

Author(s):

Zofia Machowicz-Stefaniak ◽

Beata Zimowska ◽

Ewa Zalewska

Keyword(s):

Culture Medium ◽

Pathogenic Fungi ◽

Malt Agar ◽

Thymus Vulgaris ◽

Thielaviopsis Basicola ◽

Fusarium Spp ◽

Disease Symptoms ◽

Second Year ◽

One Year ◽

The One

In 1998-2001, the healthiness of thyme cultivated in the region of Lublin was examined. Surveys were made on the one-year-old plantations of thyme at a stage of 6-week-old seedlings and just before the first harvest of the crop, as well as on the two-year-old plantations in spring and before the last harvest. The percentage of the plants showing fungal disease symptoms and the index of infection with fungi were determined. The fungi were isolated from superficially disinfected plant fragments namely from roots, bases of stem and leaves, separately, using mineral culture medium. PDA and SNA media were used to culture Fusarium spp., malt-agar and Czapek-Dox ones to culture Penicillium spp. and malt-agar, oat-agar and cherry-agar ones to culture Phoma spp. The percentage of plant infected with the fungi ranged within 12.18 and 23.05, in case of the one-year-old plantations, and within 29.91 and 43.65 in the two-year-old ones, whereas values of the index of infection ranged within 11.56 and 24.69 and within 20.75 and 43,28, respectively. Necroses were observed on roots and base of stems on one-year-old and two-year-old plantations, but in the last period of vegetation of thyme close to harvest. very often stems and leaves showed symptoms of a complete necrosis. It was found that base of stems and roots of thyme in the first and the second year of cultivation were colonized by a complex of pathogenic fungi:Fusarium spp., Rhizoctonia solani, Thielaviopsis basicola were obtained from the major part of diseased plants. Among the Fusarium species colonizing bases of stems F.culmorum, F.avenaceum, F.equiseti and F.oxysporum dominated, but from roots of thyme most often F.oxysporum, F.equiseti and F.culmorum were isolated. From stems, and particularly from leaves of thyme showing dark spots, commonly Alternaria alternata was obtained. On the other hand, shoots and leaves, but rarely roots of thyme, were colonized by various species of Phoma, particularly by Phoma exigua var. exigua. Colletotrichum gleosporioides occurred rarely on thyme in the area surveyed.

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Mycoflora of Calendula officinalis L. seeds

Acta Agrobotanica ◽

10.5586/aa.1991.004 ◽

2013 ◽

Vol 44 (1-2) ◽

pp. 49-53

Author(s):

Danuta Pięta

Keyword(s):

Botrytis Cinerea ◽

Alternaria Alternata ◽

Agar Medium ◽

Fusarium Culmorum ◽

Fusarium Avenaceum ◽

Calendula Officinalis ◽

Calendula Officinalis L

The seeds of Calendula offlcinalis harvested in the years 1985-1987 were investigated. Agar medium with nitrients was used to isolate the fungi. As a result of the mycological analysis, 3642 isolates belonglng to 23 species and dark unsporulating mycelium were obtained. Alternaria alternata dominated among the isolated fungi. Moreover, Botrytis cinerea, Fusarium culmorum, Fusarium avenaceum and Sclerotinia sc1erotiorum were obtained from the seeds.

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Nature of the "black line" produced between different biological species of the Armillaria mellea complex

Canadian Journal of Botany ◽

10.1139/b86-342 ◽

1986 ◽

Vol 64 (11) ◽

pp. 2588-2590 ◽

Cited By ~ 12

Author(s):

K. I. Mallett ◽

Y. Hiratsuka

Keyword(s):

Light Microscopy ◽

Agar Medium ◽

Biological Species ◽

Malt Agar ◽

Black Line ◽

Armillaria Mellea

The zone of antagonism or black line, formed between the confronting margins of different biological species of the Armillaria mellea complex when paired on malt agar medium, was investigated. Light microscopy showed that the black line was composed of melanized hyphal cells from both species and was bordered on either side by the bladderlike cells of the pseudosclerotial plate of each species.

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Survey, survival and control of Alternaria alternata in wheat seeds

Revista Brasileira de Sementes ◽

10.1590/s0101-31222012000300001 ◽

2012 ◽

Vol 34 (3) ◽

pp. 358-365 ◽

Cited By ~ 4

Author(s):

Ricardo Trezzi Casa ◽

Paulo Roberto Kuhnem Junior ◽

Amauri Bogo ◽

Ana Maria Munerati Belani ◽

Jonatha Marcel Bolzan ◽

...

Keyword(s):

Alternaria Alternata ◽

Agar Medium ◽

Wheat Cultivar ◽

Wheat Cultivars ◽

Wheat Seed ◽

Southern Brazil ◽

Air Humidity ◽

Potato Dextrose Agar Medium ◽

Relative Air Humidity ◽

And Control

The fungus Alternaria alternata was quantified in 75 wheat seed samples collected from three different regions of southern Brazil for Cropping and Use Value (CUV) I, II and III. Fungal presence was evaluated in two hundred disinfested seeds per sample before sowing in a potato-dextrose-agar medium + antibiotic (PDA+A). Fungus survival was evaluated every 45 days for 180 days for three seed batches from six wheat cultivars stored in propylene bags in a storehouse, with air temperature varying between 18 to 22 °C and relative air humidity around 60%. The efficacy of carboxin+thiram, difenoconazol, thiram, triadimenol, triticonazol and triticonazol + iprodione fungicides to control A. alternata was determined. A. alternata was detected in all the samples with an incidences of 39.6 %, 38.8% and 35.9% for the CUV I, CUV II and CUV III regions, respectively. The highest mean incidence of the fungus was found in the CUV I region, the coolest and most humid, and was significantly different from the other two regions. The average reduction in A. alternata viability in the wheat cultivar seeds was 49.5% during the 180 days of storage (inter-harvest period), demonstrating that infected seeds are the primary inoculum source for the fungus. The triticonazol + iprodione fungicide mixture efficiently controls A. alternata.

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