A phylogenetic and taxonomic re-evaluation of the Bipolaris - Cochliobolus - Curvularia Complex

Three genera,Cochliobolus,Bipolaris and Curvularia form a complex that contains many plant pathogens,mostly on grasses(Poaceae)with a worldwide distribution.The taxonomy of this complex is confusing as frequent nomenclatural changes and refinements have occurred.There is no clear morphological boundary between the asexual genera Bipolaris and Curvularia,and some species show intermediate morphology.We investigated this complex based on a set of ex-type cultures and collections from northern Thailand.Combined gene analysis of rDNA ITS(internal transcribed spacer),GPDH(glyceraldehyde 3-phosphate dehydrogenase),LSU(large subunit)and EF1-α(translation elongation factor 1-α)shows that this generic complex divides into two groups.Bipolaris and Cochliobolus species clustered in Group 1 along with their type species,whereas Curvularia species(including species named as Bipolaris,Cochliobolus and Curvularia)clustered in Group 2,with its generic type.The nomenclatural conflict in this complex is resolved giving priority to the more commonly used established generic names Bipolaris and Curvularia.Modern descriptions of the genera Bipolaris and Curvularia are provided and species resolved in this study are transferred to one of these genera based on their phylogeny.

Can Changes in Soil Properties in Organic Banana Production Suppress Fusarium Wilt?

Organic agriculture promotes disease suppression through healthy soils by increasing biological activity and diversity through the application of organic fertilizers and increasing organic inputs. Fusarium wilt of bananas (Fusarium oxysporum f. sp. Fcubense) (Foc), also known as Panama disease, has been a devastating disease throughout the world. So far, no fungicides or cultural measures have been found that control Foc sufficiently. The aim of this research was to assess whether organic-based farming systems were more resilient than inorganic farming systems to soil borne diseases, in particular Fusarium wilts. A survey was conducted comparing five organic and five conventional banana plantations at paired sites in north Queensland, Australia. Soil samples were collected and analysed for chemical, physical and biological soil health indicators. Disease development of F. oxysporum f. sp. lycopersici in tomatoes and Foc in bananas were studied in pot trials to pursue clues for identifying Fusarium suppressive soil traits. Organic soils from the survey showed higher microbial activity and lower disease symptom expression (both with tomatoes and bananas) than conventional soils. In the survey, nematode diversity and soil sulphate content were recurring indicators in all experiments showing close correlations to pathogen growth, disease expression and plant health. Organic soils were lower in plant-parasitic nematodes and sulphate sulphur levels and higher in nematode diversity, labile soil C and microbial indicators. Soil conduciveness or suppression of Foc appeared to be largely governed by competition for carbon. Measurement of soil microbial enzyme activity, nematode community structure and diversity and possibly sulphate sulphur seem to provide a relatively reliable indicator for general disease suppression. Differences between organic and conventional agriculture cannot be related to single management practices, but may be linked to synergies among system components.

Naming and outline of Dothideomycetes-2014 including proposals for the protection or suppression of generic names

Article 59.1,of the International Code of Nomenclature for Algae,Fungi,and Plants(ICN;Melbourne Code),which addresses the nomenclature of pleomorphic fungi,became effective from 30 July 2011.Since that date,each fungal species can have one nomenclaturally correct name in a particular classification.All other previously used names for this species will be considered as synonyms.The older generic epithet takes priority over the younger name.Any widely used younger names proposed for use,must comply with Art.57.2 and their usage should be approved by the Nomenclature Committee for Fungi(NCF).In this paper,we list all genera currently accepted by us in Dothideomycetes(belonging to 23 orders and 110 families),including pleomorphic and nonpleomorphic genera.In the case of pleomorphic genera,we follow the rulings of the current ICN and propose single generic names for future usage.The taxonomic placements of 1261 genera are listed as an outline.Protected names and suppressed names for 34 pleomorphic genera are listed separately.Notes and justifications are provided for possible proposed names after the list of genera.Notes are also provided on recent advances in our understanding of asexual and sexual morph linkages in Dothideomycetes.A phylogenetic tree based on four gene analyses supported 23 orders and 75 families,while 35 families still lack molecular data.

Molecular phylogenetic analysis reveals six new species of Diaporthe from Australia

t Six new species of Diaporthe,D.beilharziae on Indigofera australis,D.fraxini-angustifoliae on Fraxinus angustifolia subsp.oxycarpa,D.litchicola on Litchi chinensis,D.nothofagi on Nothofagus cunninghamii,D.pascoei on Persea americana and D.salicicola on Salix purpurea from Australia are described and illustrated based on morphological characteristics and molecular analyses.Three of the new species no longer produced sporulating structures in culture and two of these were morphologically described from voucher specimens.Phylogenetic relationships of the new species with other Diaporthe species are revealed by DNA sequence analyses based on the internal transcribed spacer(ITS)region,and partial regions of theβtubulin(BT)and translation elongation factor 1-alpha(TEF).

One stop shop:backbones trees for important phytopathogenic genera:Ⅰ(2014)

Many fungi are pathogenic on plants and cause significant damage in agriculture and forestry.They are also part of the natural ecosystem and may play a role in regulating plant numbers/density.Morphological identification and analysis of plant pathogenic fungi,while important,is often hampered by the scarcity of discriminatory taxonomic characters and the endophytic or inconspicuous nature of these fungi.Molecular(DNA sequence)data for plant pathogenic fungi have emerged as key information for diagnostic and classification studies,although hampered in part by non-standard laboratory practices and analytical methods.To facilitate current and future research,this study provides phylogenetic synopses for 25 groups of plant pathogenic fungi in the Ascomycota,Basidiomycota,Mucormycotina(Fungi),and Oomycota,using recent molecular data,up-to-date names,and the latest taxonomic insights.Lineagespecific laboratory protocols together with advice on their application,as well as general observations,are also provided.We hope to maintain updated backbone trees of these fungal lineages over time and to publish them jointly as new data emerge.Researchers of plant pathogenic fungi not covered by the present study are invited to join this future effort.Bipolaris,Botryosphaeriaceae,Botryosphaeria,Botrytis,Choanephora,Colletotrichum,Curvularia,Diaporthe,Diplodia,Dothiorella,Fusarium,Gilbertella,Lasiodiplodia,Mucor,Neofusicoccum,Pestalotiopsis,Phyllosticta,Phytophthora,Puccinia,Pyrenophora,Pythium,Rhizopus,Stagonosporopsis,Ustilago and Verticillium are dealt with in this paper.