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1.
Fungal Syst Evol ; 9: 19-26, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35978988

ABSTRACT

Leaf and stem spots are among the most important diseases compromising ornamental plants worldwide. In this study, Paraphoma garibaldii sp. nov. is described from leaf lesions on Campanula rapunculoides in Piedmont, Northern Italy. The new species was characterised using a polyphasic approach including morphological characterisation and a multilocus molecular phylogenetic analysis based on partial nucleotide sequences of the translation elongation factor 1-α (tef1), the internal transcribed spacers (ITS) region and the ß-tubulin (tub2) markers. Pathogenicity tests and the fulfilment of Koch's postulates confirm P. garibaldii as a novel foliar pathogen of Campanula rapunculoides. Presently, the fungal infection due to Paraphoma garibaldii is known from a single location in Italy, and further surveys are required to determine its distribution and relative importance. Citation: Guarnaccia V, Martino I, Tabone G, Crous PW, Gullino ML (2022). Paraphoma garibaldii sp. nov. causing leaf spot disease of Campanula rapunculoides in Italy. Fungal Systematics and Evolution 9: 19-26. doi: 10.3114/fuse.2022.09.03.

2.
Fungal Syst Evol ; 9: 161-200, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35978986

ABSTRACT

Seven Fusarium species complexes are treated, namely F. aywerte species complex (FASC) (two species), F. buharicum species complex (FBSC) (five species), F. burgessii species complex (FBURSC) (three species), F. camptoceras species complex (FCAMSC) (three species), F. chlamydosporum species complex (FCSC) (eight species), F. citricola species complex (FCCSC) (five species) and the F. concolor species complex (FCOSC) (four species). New species include Fusicolla elongata from soil (Zimbabwe), and Neocosmospora geoasparagicola from soil associated with Asparagus officinalis (Netherlands). New combinations include Neocosmospora akasia, N. awan, N. drepaniformis, N. duplosperma, N. geoasparagicola, N. mekan, N. papillata, N. variasi and N. warna. Newly validated taxa include Longinectria gen. nov., L. lagenoides, L. verticilliforme, Fusicolla gigas and Fusicolla guangxiensis. Furthermore, Fusarium rosicola is reduced to synonymy under N. brevis. Finally, the genome assemblies of Fusarium secorum (CBS 175.32), Microcera coccophila (CBS 310.34), Rectifusarium robinianum (CBS 430.91), Rugonectria rugulosa (CBS 126565), and Thelonectria blattea (CBS 952.68) are also announced here. Citation: Crous PW, Sandoval-Denis M, Costa MM, Groenewald JZ, van Iperen AL, Starink-Willemse M, Hernández-Restrepo M, Kandemir H, Ulaszewski B, de Boer W, Abdel-Azeem AM, Abdollahzadeh J, Akulov A, Bakhshi M, Bezerra JDP, Bhunjun CS, Câmara MPS, Chaverri P, Vieira WAS, Decock CA, Gaya E, Gené J, Guarro J, Gramaje D, Grube M, Gupta VK, Guarnaccia V, Hill R, Hirooka Y, Hyde KD, Jayawardena RS, Jeewon R, Jurjevic Z, Korsten L, Lamprecht SC, Lombard L, Maharachchikumbura SSN, Polizzi G, Rajeshkumar KC, Salgado-Salazar C, Shang Q-J, Shivas RG, Summerbell RC, Sun GY, Swart WJ, Tan YP, Vizzini A, Xia JW, Zare R, González CD, Iturriaga T, Savary O, Coton M, Coton E, Jany J-L, Liu C, Zeng Z-Q, Zhuang W-Y, Yu Z-H, Thines M (2022). Fusarium and allied fusarioid taxa (FUSA). 1. Fungal Systematics and Evolution 9: 161-200. doi: 10.3114/fuse.2022.09.08.

4.
Persoonia ; 42: 291-473, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31551622

ABSTRACT

Novel species of fungi described in this study include those from various countries as follows: Australia, Chaetomella pseudocircinoseta and Coniella pseudodiospyri on Eucalyptus microcorys leaves, Cladophialophora eucalypti, Teratosphaeria dunnii and Vermiculariopsiella dunnii on Eucalyptus dunnii leaves, Cylindrium grande and Hypsotheca eucalyptorum on Eucalyptus grandis leaves, Elsinoe salignae on Eucalyptus saligna leaves, Marasmius lebeliae on litter of regenerating subtropical rainforest, Phialoseptomonium eucalypti (incl. Phialoseptomonium gen. nov.) on Eucalyptus grandis × camaldulensis leaves, Phlogicylindrium pawpawense on Eucalyptus tereticornis leaves, Phyllosticta longicauda as an endophyte from healthy Eustrephus latifolius leaves, Pseudosydowia eucalyptorum on Eucalyptus sp. leaves, Saitozyma wallum on Banksia aemula leaves, Teratosphaeria henryi on Corymbia henryi leaves. Brazil, Aspergillus bezerrae, Backusella azygospora, Mariannaea terricola and Talaromyces pernambucoensis from soil, Calonectria matogrossensis on Eucalyptus urophylla leaves, Calvatia brasiliensis on soil, Carcinomyces nordestinensis on Bromelia antiacantha leaves, Dendryphiella stromaticola on small branches of an unidentified plant, Nigrospora brasiliensis on Nopalea cochenillifera leaves, Penicillium alagoense as a leaf endophyte on a Miconia sp., Podosordaria nigrobrunnea on dung, Spegazzinia bromeliacearum as a leaf endophyte on Tilandsia catimbauensis, Xylobolus brasiliensis on decaying wood. Bulgaria, Kazachstania molopis from the gut of the beetle Molops piceus. Croatia, Mollisia endocrystallina from a fallen decorticated Picea abies tree trunk. Ecuador, Hygrocybe rodomaculata on soil. Hungary, Alfoldia vorosii (incl. Alfoldia gen. nov.) from Juniperus communis roots, Kiskunsagia ubrizsyi (incl. Kiskunsagia gen. nov.) from Fumana procumbens roots. India, Aureobasidium tremulum as laboratory contaminant, Leucosporidium himalayensis and Naganishia indica from windblown dust on glaciers. Italy, Neodevriesia cycadicola on Cycas sp. leaves, Pseudocercospora pseudomyrticola on Myrtus communis leaves, Ramularia pistaciae on Pistacia lentiscus leaves, Neognomoniopsis quercina (incl. Neognomoniopsis gen. nov.) on Quercus ilex leaves. Japan, Diaporthe fructicola on Passiflora edulis × P. edulis f. flavicarpa fruit, Entoloma nipponicum on leaf litter in a mixed Cryptomeria japonica and Acer spp. forest. Macedonia, Astraeus macedonicus on soil. Malaysia, Fusicladium eucalyptigenum on Eucalyptus sp. twigs, Neoacrodontiella eucalypti (incl. Neoacrodontiella gen. nov.) on Eucalyptus urophylla leaves. Mozambique, Meliola gorongosensis on dead Philenoptera violacea leaflets. Nepal, Coniochaeta dendrobiicola from Dendriobium lognicornu roots. New Zealand, Neodevriesia sexualis and Thozetella neonivea on Archontophoenix cunninghamiana leaves. Norway, Calophoma sandfjordenica from a piece of board on a rocky shoreline, Clavaria parvispora on soil, Didymella finnmarkica from a piece of Pinus sylvestris driftwood. Poland, Sugiyamaella trypani from soil. Portugal, Colletotrichum feijoicola from Acca sellowiana. Russia, Crepidotus tobolensis on Populus tremula debris, Entoloma ekaterinae, Entoloma erhardii and Suillus gastroflavus on soil, Nakazawaea ambrosiae from the galleries of Ips typographus under the bark of Picea abies. Slovenia, Pluteus ludwigii on twigs of broadleaved trees. South Africa, Anungitiomyces stellenboschiensis (incl. Anungitiomyces gen. nov.) and Niesslia stellenboschiana on Eucalyptus sp. leaves, Beltraniella pseudoportoricensis on Podocarpus falcatus leaf litter, Corynespora encephalarti on Encephalartos sp. leaves, Cytospora pavettae on Pavetta revoluta leaves, Helminthosporium erythrinicola on Erythrina humeana leaves, Helminthosporium syzygii on a Syzygium sp. bark canker, Libertasomyces aloeticus on Aloe sp. leaves, Penicillium lunae from Musa sp. fruit, Phyllosticta lauridiae on Lauridia tetragona leaves, Pseudotruncatella bolusanthi (incl. Pseudotruncatellaceae fam. nov.) and Dactylella bolusanthi on Bolusanthus speciosus leaves. Spain, Apenidiella foetida on submerged plant debris, Inocybe grammatoides on Quercus ilex subsp. ilex forest humus, Ossicaulis salomii on soil, Phialemonium guarroi from soil. Thailand, Pantospora chromolaenae on Chromolaena odorata leaves. Ukraine, Cadophora helianthi from Helianthus annuus stems. USA, Boletus pseudopinophilus on soil under slash pine, Botryotrichum foricae, Penicillium americanum and Penicillium minnesotense from air. Vietnam, Lycoperdon vietnamense on soil. Morphological and culture characteristics are supported by DNA barcodes.

5.
Stud Mycol ; 92: 47-133, 2019 Mar.
Article in English | MEDLINE | ID: mdl-29997401

ABSTRACT

This paper represents the second contribution in the Genera of Phytopathogenic Fungi (GOPHY) series. The series provides morphological descriptions and information regarding the pathology, distribution, hosts and disease symptoms for the treated genera. In addition, primary and secondary DNA barcodes for the currently accepted species are included. This second paper in the GOPHY series treats 20 genera of phytopathogenic fungi and their relatives including: Allantophomopsiella, Apoharknessia, Cylindrocladiella, Diaporthe, Dichotomophthora, Gaeumannomyces, Harknessia, Huntiella, Macgarvieomyces, Metulocladosporiella, Microdochium, Oculimacula, Paraphoma, Phaeoacremonium, Phyllosticta, Proxypiricularia, Pyricularia, Stenocarpella, Utrechtiana and Wojnowiciella. This study includes the new genus Pyriculariomyces, 20 new species, five new combinations, and six typifications for older names.

6.
Persoonia ; 40: 1-25, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30504994

ABSTRACT

The diversity of fusaria in symptomatic Citrus trees in Greece, Italy and Spain was evaluated using morphological and molecular multi-locus analyses based on fragments of the calmodulin (CAM), intergenic spacer region of the rDNA (IGS), internal transcribed spacer region of the rDNA (ITS), large subunit of the rDNA (LSU), RNA polymerase largest subunit (RPB1), RNA polymerase second largest subunit (RPB2), translation elongation factor 1-alpha (EF-1α) and beta-tubulin (TUB) genes. A total of 11 species (six Fusarium spp., and five Neocosmospora spp.) were isolated from dry root rot, crown, trunk or twig canker or twig dieback of citrus trees. The most commonly isolated species were Fusarium sarcochroum, F. oxysporum and Neocosmospora solani. Three new Fusarium species are described, i.e., F. citricola and F. salinense belonging to the newly described F. citricola species complex; and F. siculi belonging to the F. fujikuroi species complex. Results of pathogenicity tests showed this new complex to include prominent canker causing agents affecting several Citrus spp. In addition, two new species are described in Neocosmospora, named N. croci and N. macrospora, the latter species being clearly differentiated from most members of this genus by producing large, up to nine-septate sporodochial conidia.

7.
Persoonia ; 40: 135-153, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30504999

ABSTRACT

Species of Diaporthe are considered important plant pathogens, saprobes, and endophytes on a wide range of plant hosts. Several species are well-known on grapevines, either as agents of pre- or post-harvest infections, including Phomopsis cane and leaf spot, cane bleaching, swelling arm and trunk cankers. In this study we explore the occurrence, diversity and pathogenicity of Diaporthe spp. associated with Vitis vinifera in major grape production areas of Europe and Israel, focusing on nurseries and vineyards. Surveys were conducted in Croatia, Czech Republic, France, Hungary, Israel, Italy, Spain and the UK. A total of 175 Diaporthe strains were isolated from asymptomatic and symptomatic shoots, branches and trunks. A multi-locus phylogeny was established based on five genomic loci (ITS, tef1, cal, his3 and tub2), and the morphological characters of the isolates were determined. Preliminary pathogenicity tests were performed on green grapevine shoots with representative isolates. The most commonly isolated species were D. eres and D. ampelina. Four new Diaporthe species described here as D. bohemiae, D. celeris, D. hispaniae and D. hungariae were found associated with affected vines. Pathogenicity tests revealed D. baccae, D. celeris, D. hispaniae and D. hungariae as pathogens of grapevines. No symptoms were caused by D. bohemiae. This study represents the first report of D. ambigua and D. baccae on grapevines in Europe. The present study improves our understanding of the species associated with several disease symptoms on V. vinifera plants, and provides useful information for effective disease management.

8.
Fungal Syst Evol ; 1: 131-140, 2018 Jun.
Article in English | MEDLINE | ID: mdl-32490364

ABSTRACT

Trunk and branch cankers are among the most important diseases compromising avocado production worldwide. A novel species, Neocosmospora perseae sp. nov. is described isolated from trunk lesions on Persea americana in the main avocado producing area of Sicily, Italy. The new species is characterised using a polyphasic approach including morphological characters and a multilocus molecular phylogenetic analysis based on partial sequences of the translation elongation factor-1α, the internal transcribed spacer regions plus the large subunit of the rDNA cistron, and the RNA polymerase II second largest subunit. Pathogenicity tests and the fulfilment of Koch's postulates confirm N. perseae as a novel canker pathogen of Persea americana.

9.
Stud Mycol ; 87: 161-185, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28720979

ABSTRACT

The genus Phyllosticta occurs worldwide, and contains numerous plant pathogenic, endophytic and saprobic species. Phyllosticta citricarpa is the causal agent of Citrus Black Spot disease (CBS), affecting fruits and leaves of several citrus hosts (Rutaceae), and can also be isolated from asymptomatic citrus tissues. Citrus Black Spot occurs in citrus-growing regions with warm summer rainfall climates, but is absent in countries of the European Union (EU). Phyllosticta capitalensis is morphologically similar to P. citricarpa, but is a non-pathogenic endophyte, commonly isolated from citrus leaves and fruits and a wide range of other hosts, and is known to occur in Europe. To determine which Phyllosticta spp. occur within citrus growing regions of EU countries, several surveys were conducted (2015-2017) in the major citrus production areas of Greece, Italy, Malta, Portugal and Spain to collect both living plant material and leaf litter in commercial nurseries, orchards, gardens, backyards and plant collections. A total of 64 Phyllosticta isolates were obtained from citrus in Europe, of which 52 were included in a multi-locus (ITS, actA, tef1, gapdh, LSU and rpb2 genes) DNA dataset. Two isolates from Florida (USA), three isolates from China, and several reference strains from Australia, South Africa and South America were included in the overall 99 isolate dataset. Based on the data obtained, two known species were identified, namely P. capitalensis (from asymptomatic living leaves of Citrus spp.) in Greece, Italy, Malta, Portugal and Spain, and P. citricarpa (from leaf litter of C. sinensis and C. limon) in Italy, Malta and Portugal. Moreover, two new species were described, namely P. paracapitalensis (from asymptomatic living leaves of Citrus spp.) in Italy and Spain, and P. paracitricarpa (from leaf litter of C. limon) in Greece. On a genotypic level, isolates of P. citricarpa populations from Italy and Malta (MAT1-2-1) represented a single clone, and those from Portugal (MAT1-1-1) another. Isolates of P. citricarpa and P. paracitricarpa were able to induce atypical lesions (necrosis) in artificially inoculated mature sweet orange fruit, while P. capitalensis and P. paracapitalensis induced no lesions. The Phyllosticta species recovered were not found to be widespread, and were not associated with disease symptoms, indicating that the fungi persisted over time, but did not cause disease.

10.
Persoonia ; 39: 32-50, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29503469

ABSTRACT

Species of Colletotrichum are considered important plant pathogens, saprobes, and endophytes on a wide range of plant hosts. Several species are well-known on citrus, either as agents of pre- or post-harvest infections, such as anthracnose, postbloom fruit drop, tear stain and stem-end rot on fruit, or as wither-tip of twigs. In this study we explored the occurrence, diversity and pathogenicity of Colletotrichum spp. associated with Citrus and allied genera in European orchards, nurseries and gardens. Surveys were carried out during 2015 and 2016 in Greece, Italy, Malta, Portugal and Spain. A total of 174 Colletotrichum strains were isolated from symptomatic leaves, fruits, petals and twigs. A multi-locus phylogeny was established based on seven genomic loci (ITS, GAPDH, ACT, CAL, CHS-1, HIS3 and TUB2), and the morphological characters of the isolates determined. Preliminary pathogenicity tests were performed on orange fruits with representative isolates. Colletotrichum strains were identified as members of three major species complexes. Colletotrichum gloeosporioides s.str. and two novel species (C. helleniense and C. hystricis) were identified in the C. gloeosporioides species complex. Colletotrichum karstii, C. novae-zelandiae and two novel species (C. catinaense and C. limonicola) in the C. boninense species complex, and C. acutatum s.str. was also isolated as member of C. acutatum species complex. Colletotrichum gloeosporioides and C. karstii were the predominant species of Colletotrichum isolated. This study represents the first report of C. acutatum on citrus in Europe, and the first detection of C. novae-zelandiae from outside New Zealand. Pathogenicity tests revealed C. gloeosporioides s.str. to be the most virulent species on fruits. The present study improves our understanding of species associated with several disease symptoms on citrus fruits and plants, and provides useful information for effective disease management.

11.
Persoonia ; 39: 270-467, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29503478

ABSTRACT

Novel species of fungi described in this study include those from various countries as follows: Antarctica: Cadophora antarctica from soil. Australia: Alfaria dandenongensis on Cyperaceae, Amphosoma persooniae on Persoonia sp., Anungitea nullicana on Eucalyptus sp., Bagadiella eucalypti on Eucalyptus globulus, Castanediella eucalyptigena on Eucalyptus sp., Cercospora dianellicola on Dianella sp., Cladoriella kinglakensis on Eucalyptus regnans, Cladoriella xanthorrhoeae (incl. Cladoriellaceae fam. nov. and Cladoriellales ord. nov.) on Xanthorrhoea sp., Cochlearomyces eucalypti (incl. Cochlearomyces gen. nov. and Cochlearomycetaceae fam. nov.) on Eucalyptus obliqua, Codinaea lambertiae on Lambertia formosa, Diaporthe obtusifoliae on Acacia obtusifolia, Didymella acaciae on Acacia melanoxylon, Dothidea eucalypti on Eucalyptus dalrympleana, Fitzroyomyces cyperi (incl. Fitzroyomyces gen. nov.) on Cyperaceae, Murramarangomyces corymbiae (incl. Murramarangomyces gen. nov., Murramarangomycetaceae fam. nov. and Murramarangomycetales ord. nov.) on Corymbia maculata, Neoanungitea eucalypti (incl. Neoanungitea gen. nov.) on Eucalyptus obliqua, Neoconiothyrium persooniae (incl. Neoconiothyrium gen. nov.) on Persoonia laurina subsp. laurina, Neocrinula lambertiae (incl. Neocrinulaceae fam. nov.) on Lambertia sp., Ochroconis podocarpi on Podocarpus grayae, Paraphysalospora eucalypti (incl. Paraphysalospora gen. nov.) on Eucalyptus sieberi, Pararamichloridium livistonae (incl. Pararamichloridium gen. nov., Pararamichloridiaceae fam. nov. and Pararamichloridiales ord. nov.) on Livistona sp., Pestalotiopsis dianellae on Dianella sp., Phaeosphaeria gahniae on Gahnia aspera, Phlogicylindrium tereticornis on Eucalyptus tereticornis, Pleopassalora acaciae on Acacia obliquinervia, Pseudodactylaria xanthorrhoeae (incl. Pseudodactylaria gen. nov., Pseudodactylariaceae fam. nov. and Pseudodactylariales ord. nov.) on Xanthorrhoea sp., Pseudosporidesmium lambertiae (incl. Pseudosporidesmiaceae fam. nov.) on Lambertia formosa, Saccharata acaciae on Acacia sp., Saccharata epacridis on Epacris sp., Saccharata hakeigena on Hakea sericea, Seiridium persooniae on Persoonia sp., Semifissispora tooloomensis on Eucalyptus dunnii, Stagonospora lomandrae on Lomandra longifolia, Stagonospora victoriana on Poaceae, Subramaniomyces podocarpi on Podocarpus elatus, Sympoventuria melaleucae on Melaleuca sp., Sympoventuria regnans on Eucalyptus regnans, Trichomerium eucalypti on Eucalyptus tereticornis, Vermiculariopsiella eucalypticola on Eucalyptus dalrympleana, Verrucoconiothyrium acaciae on Acacia falciformis, Xenopassalora petrophiles (incl. Xenopassalora gen. nov.) on Petrophile sp., Zasmidium dasypogonis on Dasypogon sp., Zasmidium gahniicola on Gahnia sieberiana.Brazil: Achaetomium lippiae on Lippia gracilis, Cyathus isometricus on decaying wood, Geastrum caririense on soil, Lycoperdon demoulinii (incl. Lycoperdon subg. Arenicola) on soil, Megatomentella cristata (incl. Megatomentella gen. nov.) on unidentified plant, Mutinus verrucosus on soil, Paraopeba schefflerae (incl. Paraopeba gen. nov.) on Schefflera morototoni, Phyllosticta catimbauensis on Mandevilla catimbauensis, Pseudocercospora angularis on Prunus persica, Pseudophialophora sorghi on Sorghum bicolor, Spumula piptadeniae on Piptadenia paniculata.Bulgaria: Yarrowia parophonii from gut of Parophonus hirsutulus. Croatia: Pyrenopeziza velebitica on Lonicera borbasiana.Cyprus: Peziza halophila on coastal dunes. Czech Republic: Aspergillus contaminans from human fingernail. Ecuador: Cuphophyllus yacurensis on forest soil, Ganoderma podocarpense on fallen tree trunk. England: Pilidium anglicum (incl. Chaetomellales ord. nov.) on Eucalyptus sp. France: Planamyces parisiensis (incl. Planamyces gen. nov.) on wood inside a house. French Guiana: Lactifluus ceraceus on soil. Germany: Talaromyces musae on Musa sp. India: Hyalocladosporiella cannae on Canna indica, Nothophoma raii from soil. Italy: Setophaeosphaeria citri on Citrus reticulata, Yuccamyces citri on Citrus limon.Japan: Glutinomyces brunneus (incl. Glutinomyces gen. nov.) from roots of Quercus sp. Netherlands (all from soil): Collariella hilkhuijsenii, Fusarium petersiae, Gamsia kooimaniorum, Paracremonium binnewijzendii, Phaeoisaria annesophieae, Plectosphaerella niemeijerarum, Striaticonidium deklijnearum, Talaromyces annesophieae, Umbelopsis wiegerinckiae, Vandijckella johannae (incl. Vandijckella gen. nov. and Vandijckellaceae fam. nov.), Verhulstia trisororum (incl. Verhulstia gen. nov.). New Zealand: Lasiosphaeria similisorbina on decorticated wood. Papua New Guinea: Pseudosubramaniomyces gen. nov. (based on Pseudosubramaniomyces fusisaprophyticus comb. nov.). Slovakia: Hemileucoglossum pusillum on soil. South Africa: Tygervalleyomyces podocarpi (incl. Tygervalleyomyces gen. nov.) on Podocarpus falcatus.Spain: Coniella heterospora from herbivorous dung, Hymenochaete macrochloae on Macrochloa tenacissima, Ramaria cistophila on shrubland of Cistus ladanifer.Thailand: Polycephalomyces phaothaiensis on Coleoptera larvae, buried in soil. Uruguay: Penicillium uruguayense from soil. Vietnam: Entoloma nigrovelutinum on forest soil, Volvariella morozovae on wood of unknown tree. Morphological and culture characteristics along with DNA barcodes are provided.

12.
Persoonia ; 36: 316-458, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27616795

ABSTRACT

Novel species of fungi described in the present study include the following from Australia: Vermiculariopsiella eucalypti, Mulderomyces natalis (incl. Mulderomyces gen. nov.), Fusicladium paraamoenum, Neotrimmatostroma paraexcentricum, and Pseudophloeospora eucalyptorum on leaves of Eucalyptus spp., Anungitea grevilleae (on leaves of Grevillea sp.), Pyrenochaeta acaciae (on leaves of Acacia sp.), and Brunneocarpos banksiae (incl. Brunneocarpos gen. nov.) on cones of Banksia attenuata. Novel foliicolous taxa from South Africa include Neosulcatispora strelitziae (on Strelitzia nicolai), Colletotrichum ledebouriae (on Ledebouria floridunda), Cylindrosympodioides brabejum (incl. Cylindrosympodioides gen. nov.) on Brabejum stellatifolium, Sclerostagonospora ericae (on Erica sp.), Setophoma cyperi (on Cyperus sphaerocephala), and Phaeosphaeria breonadiae (on Breonadia microcephala). Novelties described from Robben Island (South Africa) include Wojnowiciella cissampeli and Diaporthe cissampeli (both on Cissampelos capensis), Phaeotheca salicorniae (on Salicornia meyeriana), Paracylindrocarpon aloicola (incl. Paracylindrocarpon gen. nov.) on Aloe sp., and Libertasomyces myopori (incl. Libertasomyces gen. nov.) on Myoporum serratum. Several novelties are recorded from La Réunion (France), namely Phaeosphaeriopsis agapanthi (on Agapanthus sp.), Roussoella solani (on Solanum mauritianum), Vermiculariopsiella acaciae (on Acacia heterophylla), Dothiorella acacicola (on Acacia mearnsii), Chalara clidemiae (on Clidemia hirta), Cytospora tibouchinae (on Tibouchina semidecandra), Diaporthe ocoteae (on Ocotea obtusata), Castanediella eucalypticola, Phaeophleospora eucalypticola and Fusicladium eucalypticola (on Eucalyptus robusta), Lareunionomyces syzygii (incl. Lareunionomyces gen. nov.) and Parawiesneriomyces syzygii (incl. Parawiesneriomyces gen. nov.) on leaves of Syzygium jambos. Novel taxa from the USA include Meristemomyces arctostaphylos (on Arctostaphylos patula), Ochroconis dracaenae (on Dracaena reflexa), Rasamsonia columbiensis (air of a hotel conference room), Paecilomyces tabacinus (on Nicotiana tabacum), Toxicocladosporium hominis (from human broncoalveolar lavage fluid), Nothophoma macrospora (from respiratory secretion of a patient with pneumonia), and Penidiellopsis radicularis (incl. Penidiellopsis gen. nov.) from a human nail. Novel taxa described from Malaysia include Prosopidicola albizziae (on Albizzia falcataria), Proxipyricularia asari (on Asarum sp.), Diaporthe passifloricola (on Passiflora foetida), Paramycoleptodiscus albizziae (incl. Paramycoleptodiscus gen. nov.) on Albizzia falcataria, and Malaysiasca phaii (incl. Malaysiasca gen. nov.) on Phaius reflexipetalus. Two species are newly described from human patients in the Czech Republic, namely Microascus longicollis (from toenails of patient with suspected onychomycosis), and Chrysosporium echinulatum (from sole skin of patient). Furthermore, Alternaria quercicola is described on leaves of Quercus brantii (Iran), Stemphylium beticola on leaves of Beta vulgaris (The Netherlands), Scleroderma capeverdeanum on soil (Cape Verde Islands), Scleroderma dunensis on soil, and Blastobotrys meliponae from bee honey (Brazil), Ganoderma mbrekobenum on angiosperms (Ghana), Geoglossum raitviirii and Entoloma kruticianum on soil (Russia), Priceomyces vitoshaensis on Pterostichus melas (Carabidae) (Bulgaria) is the only one for which the family is listed, Ganoderma ecuadoriense on decaying wood (Ecuador), Thyrostroma cornicola on Cornus officinalis (Korea), Cercophora vinosa on decorticated branch of Salix sp. (France), Coprinus pinetorum, Coprinus littoralis and Xerocomellus poederi on soil (Spain). Two new genera from Colombia include Helminthosporiella and Uwemyces on leaves of Elaeis oleifera. Two species are described from India, namely Russula intervenosa (ectomycorrhizal with Shorea robusta), and Crinipellis odorata (on bark of Mytragyna parviflora). Novelties from Thailand include Cyphellophora gamsii (on leaf litter), Pisolithus aureosericeus and Corynascus citrinus (on soil). Two species are newly described from Citrus in Italy, namely Dendryphiella paravinosa on Citrus sinensis, and Ramularia citricola on Citrus floridana. Morphological and culture characteristics along with ITS nrDNA barcodes are provided for all taxa.

13.
Oncogene ; 31(29): 3431-43, 2012 Jul 19.
Article in English | MEDLINE | ID: mdl-22056878

ABSTRACT

All-trans retinoic acid (ATRA), the only clinically available cyto-differentiating agent, has potential for the therapy/chemoprevention of breast carcinoma. Given the heterogeneous nature of this tumor, a rational use of ATRA and derivatives (retinoids) in the clinic requires the identification of patients that would benefit from retinoid-based protocols. Here, we demonstrate that 23-32% of the human ERBB2(+) breast cancers show coamplification of retinoic acid receptor alpha (RARA), encoding the retinoic acid receptor, RARα. This represents a novel subtype of breast cancer characterized by remarkable sensitivity to ATRA and RARα agonists, regardless of positivity to the estrogen receptor, a known modulator of retinoid sensitivity. In estrogen-receptor-negative cellular models showing coamplification of ERBB2 and RARA, simultaneous targeting of the corresponding gene products with combinations of lapatinib and ATRA causes synergistic growth inhibition, cyto-differentiation and apoptosis. This provides proof-of-principle that coamplification of ERBB2 and RARA can be exploited for the stratified and targeted therapy of a novel subtype of breast cancer patients, with an approach characterized by tumor cell selectivity and low predicted toxicity. The available cellular models were exploited to define the molecular mechanisms underlying the antitumor activity of combinations between lapatinib and ATRA. Global gene expression and functional approaches provide evidence for three components of the antiproliferative/apoptotic responses triggered by lapatinib+ATRA. Induction of the retinoid-dependent RARRES3 protein by ATRA stabilizes the effect of lapatinib inhibiting ERBB2 phosphorylation. Upregulation and activation of the transcription factor FOXO3A integrates ATRA-dependent transcriptional and lapatinib-dependent posttranscriptional signals, controlling the levels of effector proteins like the antiapoptotic factor, BIRC5. Stimulation of the TGFß pathway by ATRA mediates other components of the apoptotic process set in motion by simultaneous targeting of ERBB2 and RARα.


Subject(s)
Antineoplastic Agents/pharmacology , Breast Neoplasms/genetics , Gene Amplification/drug effects , Quinazolines/pharmacology , Receptor, ErbB-2/genetics , Receptors, Retinoic Acid/genetics , Tretinoin/pharmacology , Breast Neoplasms/metabolism , Cell Line, Tumor , Drug Synergism , Forkhead Box Protein O3 , Forkhead Transcription Factors/metabolism , Humans , Lapatinib , Phosphorylation/drug effects , Receptor, ErbB-2/antagonists & inhibitors , Receptor, ErbB-2/metabolism , Receptors, Retinoic Acid/metabolism , Retinoic Acid Receptor alpha , Smad3 Protein/metabolism , Transcription, Genetic/drug effects , Transcriptome/drug effects , Transforming Growth Factor beta/metabolism
14.
Plant Dis ; 95(12): 1588, 2011 Dec.
Article in English | MEDLINE | ID: mdl-30731997

ABSTRACT

In June 2010, a widespread damping-off was noticed in a commercial nursery in eastern Sicily on ~20,000 potted 2-month-old strawberry tree (Arbutus unedo L.) seedlings. More than 40% of the seedlings showed disease symptoms including brown lesions at the seedling crown above and below the soil line that expanded rapidly to girdle the stem. Stem lesions were followed by death of the entire seedling in a few days. Diseased stem and crown tissues of 20 seedlings were surface disinfested for 2 min in 1% NaOCl, rinsed in sterile water, plated on potato dextrose agar amended with 100 mg/liter of streptomycin sulfate, and incubated at 25°C in the dark. Fungal isolates with mycelial and morphological characteristics of Colletotrichum spp. were isolated from all seedlings. Fungal colonies were pale orange or gray without carmine pigments. On carnation leaf agar (CLA), single-spore isolates produced many orange masses of hyaline, aseptate conidia with a cylindrical to ellipsoidal shape, rounded apex, and 11 to 15 µm long and 3 to 4.5 µm wide (average 13.2 × 3.7 µm). The pointed conidia of 10 isolates were morphologically similar. DNA isolation was performed with the Wizard Magnetic DNA Purification Kit (Promega, Madison, WI) following the manufacturer's instructions with some modifications. A PCR assay was conducted on two representative isolates (ITEM 13492 and ITEM 13493) by analyzing sequences of gene benA (coding ß-tubulin protein) using the primers T1 and T10 reported by O'Donnell and Cigelnik (1). BenA gene sequence of ITEM 13492 exhibited an identity of 99.8% to C. simmondsii strain BRIP 4704 (GenBank No. GU183277), while BenA gene sequence of ITEM 13493 exhibited an identity of 100% to C. acutatum strain BRIP52695 (GenBank No. GU183314). The identification of these two species was made by comparing the internal transcribed spacer region and BenA sequences of these two strains with that deposited by Shivas and Tan (2). Morphological characteristics, as well as the PCR assay, identified the isolates as Colletotrichum acutatum J.H. Simmonds and C. simmondsii R.G. Shivas & Y. P. Tan (2,3). Pathogenicity tests were carried out on 2-month-old seedlings of strawberry tree grown on alveolar trays. Conidial suspensions of two isolates (ITEM 13492 and ITEM 13493) were obtained from 14-day-old single-spore colonies on CLA, then adjusted to 105 conidia per ml and sprayed on seedlings. Fifty seedlings for each isolate were used. The same number of seedlings was mock inoculated with sterile distilled water. All seedlings were enclosed for 4 days in plastic bags and placed in a growth chamber at 24 ± 1°C for 45 days. Identical symptoms to those observed in the nurseries appeared 30 days after inoculation, and after 45 days, 80% of the plants were dead. No difference in virulence between the two isolates was observed and no symptoms were detected on the control plants. C. acutatum and C. simmondsii were successfully reisolated from all symptomatic tissues and identified as previously described, completing Koch's postulates. To our knowledge, this is the first report in the world of C. acutatum and C. simmondsii on strawberry tree. This suggests that Colletotrichum spp. may be important pathogens of young seedlings of strawberry tree in nurseries. References: (1) K. O'Donnell and E. Cigelnik. Mol. Phylo. Evol. 7:103, 1997. (2) R. G. Shivas and Y. P. Tan. Fungal Divers. 39:111, 2009. (3) B. C. Sutton. Page 523 in: The Coelomycetes. Commonwealth Mycological Institute, Kew, Surrey, England, 1980.

15.
Plant Dis ; 95(9): 1194, 2011 Sep.
Article in English | MEDLINE | ID: mdl-30732024

ABSTRACT

The genus Passiflora (Passifloraceae family) contains more than 500 species and several hybrids. In Italy, some of these species and hybrids are grown as ornamental evergreen vines or shrubs. During August and September 2010, a crown and root rot was observed in a stock of approximately 6,000 potted 2-year-old plants of Passiflora mollissima (Kunth) Bailey, commonly known as the banana passionflower, in a nursery located in eastern Sicily (southern Italy). Disease incidence was approximately 20%. Disease symptoms consisted of water-soaked lesions at the crown and a root rot. Successively, older crown lesions turned light brown to brown and expanded to girdle the stem. As crown and root rot progressed, basal leaves turned yellow and gradually became necrotic and infected plants wilted and died. A fungus with mycelial and morphological characteristics of Rhizoctonia solani Kühn was consistently isolated from crown lesions and brown decaying roots when plated on potato dextrose agar (PDA) amended with streptomycin sulfate at 100 µg/ml. Fungal colonies were initially white, turned brown with age, and produced irregularly shaped, brown sclerotia. Mycelium was branched at right angles with a septum near the branch with a slight constriction at the branch base. Hyphal cells removed from 10 representative cultures grown at 25°C on 2% water agar were determined to be multinucleate when stained with 1% safranin O and 3% KOH solution (1) and examined at ×400. Anastomosis groups were determined by pairing isolates on 2% water agar in petri plates (4). Pairings were made with tester strains of AG-1, AG-2, AG-3, AG-4, AG-5, AG-6, and AG-11. Anastomosis was observed only with tester isolates of AG-4 (3). Pathogenicity tests were performed on container-grown, healthy, 3-month-old cuttings. Twenty plants of P. mollissima were inoculated near the base of the stem with five 1-cm2 PDA plugs from 5-day-old mycelial plugs obtained from two representative cultures. The same number of plants served as uninoculated controls. Plants were maintained at 25°C and 95% relative humidity with a 12-h fluorescent light/dark regimen. Wilt symptoms due to crown and root rot, identical to ones observed in the nursery, appeared 7 to 8 days after inoculation with either of the two isolates and all plants died within 20 days. No disease was observed on control plants. R. solani AG-4 was reisolated from symptomatic tissues and identified as previously described, confirming its pathogenicity. Damping-off or crown and root rot due to R. solani were previously detected on P. edulis in Brazil, Africa, India, Oceania, and Australia (2). To our knowledge, this is the first report of R. solani causing crown and root rot on P. mollissima. References: (1) R. J. Bandoni. Mycologia 71:873, 1979. (2) J. L. Bezerra and M. L. Oliveira. Fitopathol. Brasil. 9:273, 1984. (3) D. E. Carling. Page 37 in: Grouping in Rhizoctonia solani by Hyphal Anastomosis Reactions. Kluwer Academic Publishers, the Netherlands, 1996. (4) C. C. Tu and J. W. Kimbrough. Mycologia 65:941, 1973.

16.
Plant Dis ; 95(1): 78, 2011 Jan.
Article in English | MEDLINE | ID: mdl-30743677

ABSTRACT

Pink ipê or pink lapacho (Tabebuia impetiginosa Martius ex DC., family Bignoniaceae) is one of the most attractive blooming trees in the world. In Europe, pink ipê is widely used as an ornamental tree in landscaped gardens and public areas. In August 2010, a widespread damping-off was observed in a stock of approximately 100,000 potted 2-month-old seedlings in a nursery in eastern Sicily (Italy). The seedlings were being watered with overhead irrigation. More than 5% of the seedlings showed disease symptoms. Initial symptoms were black lesions at the seedling crown that expanded rapidly to girdle the stem. On infected seedlings, leaves turned black and gradually died. Black extended stem lesions were followed by death of the entire seedling in a few days. A fungus with mycelial and morphological characteristics of Rhizoctonia solani Kühn was consistently isolated from crown and stem lesions when plated on potato dextrose agar (PDA) amended with streptomycin sulfate at 100 µg/ml. Fungal colonies were initially white, turned brown with age, and produced irregularly shaped, brown sclerotia. Mycelium was branched at right angles with a septum near the branch and a slight constriction at the branch base. Hyphal cells removed from cultures grown at 25°C on 2% water agar were determined to be multinucleate when stained with 1% safranin O and 3% KOH solution (1) and examined at ×400. Anastomosis groups were determined by pairing isolates with tester strains AG-1 IA, AG-2-2-1, AG-2-2IIIB, AG-2-2IV, AG-3, AG-4, AG-5, AG-6, and AG-11 on 2% water agar in petri plates (4). Anastomosis was observed only with tester isolates of AG-4, giving both C2 and C3 reactions (2). Pathogenicity tests were performed on container-grown, healthy, 3-month-old seedlings. Forty seedlings of T. impetiginosa were inoculated near the base of the stem with two 1-cm2 PDA plugs from 5-day-old mycelial cultures. The same number of plants only inoculated with PDA plugs served as controls. Plants were incubated in a growth chamber and maintained at 25°C and 95% relative humidity on a 12-h fluorescent light/dark regimen. Crown and stem lesions identical to those observed in the nursery appeared 5 days after inoculation and all plants died within 25 days. No disease was observed on control plants. R. solani AG-4 was reisolated from symptomatic tissues and identified as previously described. R. solani AG-4 was previously detected in the same nursery on Chamaerops humilis (3). To our knowledge, this is the first report of R. solani causing damping-off on T. impetiginosa. References: (1) R. J. Bandoni. Mycologia 71:873, 1979. (2) D. E. Carling. Page 37 in: Grouping in Rhizoctonia solani by Hyphal Anastomosis Reactions. Kluwer Academic Publishers, the Netherlands, 1996. (3) G. Polizzi et al. Plant Dis. 94:125, 2010. (4) C. C. Tu and J. W. Kimbrough. Mycologia 65:941, 1973.

17.
Persoonia ; 27: 73-9, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22403477

ABSTRACT

Calonectria spp. are important pathogens of ornamental plants in nurseries, especially in the Northern Hemisphere. They are commonly associated with a wide range of disease symptoms of roots, leaves and shoots. During a recent survey in Tunisia, a number of Calonectria spp. were isolated from tissues of ornamental plants showing symptoms of leaf spot, crown and root rot. The aim of this study was to identify these Calonectria spp. using morphological and DNA sequence comparisons. Two previously undescribed Calonectria spp., C. pseudomexicana sp. nov. and C. tunisiana sp. nov., were recognised. Calonectria mexicana and C. polizzii are newly reported for the African continent. Pathogenicity tests with all four Calonectria spp. showed that they are able to cause disease on seedlings of Callistemon spp., Dodonaea viscosa, Metrosideros spp. and Myrtus communis.

18.
Plant Dis ; 95(7): 877, 2011 Jul.
Article in English | MEDLINE | ID: mdl-30731709

ABSTRACT

Philotheca myoporoides (DC.) M.J. Bayly (previously known as Eriostemon myoporoides), commonly called long-leaf waxflower and native to eastern Australia (Rutaceae family), is a hardy compact shrub or small tree occurring in subtropical to cool temperate regions. P. myoporoides is cultivated in Sicily (Italy) for its ornamental appeal. During April of 2010, a widespread wilting was observed on approximately 80% of 2,000 1-year-old, potted long-leaf waxflower plants grown in a commercial nursery near Catania (eastern Sicily, Italy). Internally, symptomatic plants had conspicuous vascular brown discoloration from the crown to the canopy. Diseased crown and stem tissues of 20 plants 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 tissues. Colonies with white or light purple aerial mycelia and violet pigmentation on the underside of the cultures developed after 9 days. On carnation leaf agar, 20 single-spore isolates produced microconidia on short monophialides, macroconidia that were three to five septate with a pedicellate base, and solitary and double-celled or aggregate chlamydospores. A PCR assay was conducted on one representative isolate (ITEM 13490) by analyzing sequences of the benA gene (coding ß-tubulin protein) and CaM gene (coding calmodulin protein) using the primers reported by O'Donnell et al. (1). The benA gene sequences of ITEM 13490 (GenBank No. FR828825) exhibited an identity of 100% to Fusarium oxysporum f. sp. radicis-lycopersici strain ATCC 52429 (GenBank No. DQ092480). CaM gene sequences of ITEM 13490 (GenBank No. FR828826) exhibited an identity of 99.6% to F. oxysporum strain ITEM 2367 (GenBank No. AJ560774). Morphological characteristics of the 20 isolates, as well as the PCR assay on a representative strain, identified the isolates associated with disease symptoms as F. oxysporum Schlechtend.:Fr. A pathogenicity test was performed by placing two 1-cm2 plugs of PDA from 9-day-old mycelial cultures near the crown on potted, healthy, 2-month-old cuttings of P. myoporoides. Thirty plants were inoculated with strain ITEM 13490 and the same number of plants served as noninoculated controls. All plants were enclosed for 4 days in plastic bags and placed in a growth chamber at 25 ± 1°C. Plants were then moved to a greenhouse where temperatures ranged from 23 to 27°C. First symptoms, which were identical to those observed in the nursery, developed on one plant 15 days after inoculation. Wilting was detected on all plants after 30 days. Control plants remained symptomless. F. oxysporum was successfully reisolated from symptomatic crown and stem tissues and identified as described above, fulfilling Koch's postulates. To our knowledge, this is the first report of F. oxysporum causing disease of P. myoporoides worldwide. Moreover, this pathogen was recently reported in the same nursery on Eremophila sp. (2), confirming the presence of Fusarium wilt as a potential threat to ornamental plant production in this area, and necessitates the innovation and development of disinfection methods for alveolar trays, greenhouses, and various propagation materials to reduce future disease outbreaks. References: (1) K. O'Donnell et al. Mycoscience 41:61, 2000. (2) G. Polizzi et al. Plant Dis 94:1509, 2010.

19.
Plant Dis ; 94(12): 1509, 2010 Dec.
Article in English | MEDLINE | ID: mdl-30743379

ABSTRACT

Eremophila spp. (Myoporaceae family), endemic to Australia, are evergreen shrubs or small trees occurring in arid, semi-arid, tropical, or temperate regions. In Europe, Eremophila spp. are grown for their horticultural appeal. During 2009 and 2010, extensive wilting was observed on 2-month to 1-year-old potted plants of Eremophila laanii F. Muell., E. glabra subsp. carnosa Chinnock, and E. maculata (Ker Gawl.) F. Muell. grown in a commercial nursery near Catania (southern Italy). Internally, symptomatic plants had conspicuous vascular 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 tissues. Colonies with purple mycelia and violet reverse colors developed after 9 days. On carnation leaf agar, single-spore isolates produced microconidia on short monophialides, macroconidia that were three to five septate with a pedicellate base, and solitary and double-celled or aggregated chlamydospores. A PCR assay was conducted on two representative isolates (ITEM 12591 and ITEM 12592) by analyzing sequences of the partial CaM gene (coding calmodulin protein) and benA (coding beta-tubulin protein) using the primers as reported by O'Donnell et al. (1). Calmodulin sequences of ITEM 12951 and ITEM 12952 isolates (GenBank Nos. FR671157 and FR671158) exhibited 99.8 and 99.5% identity with Fusarium oxysporum strain ITEM 2367 (GenBank No. AJ560774), respectively, and had 99.5% homology between them. BenA gene sequences of ITEM 12951 (GenBank No. FR671426) exhibited an identity of 100% to F. oxysporum f. sp. vasinfectum strain CC-612-3 (GenBank No. AY714092.1), and benA gene sequences of ITEM 12952 (GenBank No. FR671427) exhibited an identity of 100% to F. oxysporum f. sp. vasinfectum strain LA 140 (GenBank No. FJ466740.1), whereas the homology between the two strains is 99.5%. Morphological characteristics, as well as CaM and benA sequences, identified the isolates as F. oxysporum Schlechtend:Fr. Pathogenicity tests were performed by placing 1-cm2 plugs of PDA from 9-day-old mycelial cultures near the crown on potted, healthy, 3-month-old cuttings of E. laanii, E. glabra subsp. carnosa, and E. maculata. Twenty plants for each species were inoculated with each isolate. The same number of plants served as noninoculated controls. All plants were enclosed for 4 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 23 to 27°C. Symptoms identical to those observed in the nursery developed 20 days after inoculation with both strains. Crown and stem discoloration was detected in all inoculated plants after 45 days. Wilting was detected on 15% of plants. Control plants remained symptomless. F. oxysporum was consistently reisolated from symptomatic tissues and identified as previously above. To our knowledge, this is the first report of F. oxysporum causing disease of Eremophila spp. worldwide. Reference: (1) K. O'Donnell et al. Mycoscience 41:61, 2000.

20.
Plant Dis ; 94(1): 125, 2010 Jan.
Article in English | MEDLINE | ID: mdl-30754403

ABSTRACT

Mediterranean fan palm (Chamaerops humilis L.), one of just two autochthonous European palms, is native to the western Mediterranean Region in southwestern Europe and northwestern Africa. It can be found growing wild in the Mediterranean area. In Europe, this species is very popular as an ornamental plant. In March 2009, a widespread damping-off was observed in a stock of approximately 30,000 potted 1-month-old plants of C. humilis cv. Vulcano in a nursery in eastern Sicily. Disease incidence was approximately 20%. Disease symptoms consisted of lesions at the seedling shoot (plumule). Stem lesions were initially orange, turned brown, and followed by death of the entire plumule or eophyll. A fungus with mycelial and morphological characteristics of Rhizoctonia solani Kühn was consistently isolated from lesions when plated on potato dextrose agar (PDA) amended with streptomycin sulfate at 100 µg/ml. Fungal colonies were initially white, turned brown with age, and produced irregularly shaped, brown sclerotia. Mycelium was branched at right angles with a septum near the branch and a slight constriction at the branch base. Hyphal cells removed from cultures grown at 25°C on 2% water agar were determined to be multinucleate when stained with 1% safranin O and 3% KOH solution (1) and examined at ×400. Anastomosis groups were determined by pairing isolates with tester strains AG-1 IA, AG-2-2-1, AG-2-2IIIB, AG-2-2IV, AG-3, AG-4, AG-5, AG-6, and AG-11 on 2% water agar in petri plates (3). Anastomosis was observed only with tester isolates of AG-4, giving both C2 and C3 reactions (2). One representative isolate obtained from symptomatic tissues was deposited at the Fungal Biodiversity Centre, Centraalbureau voor Schimmelcultures (CBS No. 125095). Pathogenicity tests were performed on container-grown, healthy, 1-month-old seedlings. Twenty plants of C. humilis cv. Vulcano were inoculated near the base of the stem with two 1-cm2 PDA plugs from 5-day-old mycelial cultures. The same number of plants served as uninoculated controls. Plants were incubated in a growth chamber and maintained at 25°C and 95% relative humidity on a 12-h fluorescent light/dark regimen. Symptoms identical to those observed in the nursery appeared 5 days after inoculation and all plants died within 20 days. No disease was observed on control plants. A fungus identical in culture morphology to R. solani AG-4 was consistently reisolated from symptomatic tissues, confirming its pathogenicity. To our knowledge, this is the first report in the world of R. solani causing damping-off on Mediterranean fan palm. References: (1) R. J. Bandoni. Mycologia 71:873, 1979. (2) D. E. Carling. Page 37 in: Grouping in Rhizoctonia solani by Hyphal Anastomosis Reactions. Kluwer Academic Publishers, the Netherlands, 1996. (3) C. C. Tu and J. W. Kimbrough. Mycologia 65:941, 1973.

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