Rafael F. Alfenas

Fungal Planet description sheets: 69–91

Novel species of microfungi described in the present study include the following from Australia: Bagadiella victoriae and Bagadiella koalae on Eucalyptus spp., Catenulostroma eucalyptorum on Eucalyptus laevopinea, Cercospora eremochloae on Eremochloa bimaculata, Devriesia queenslandica on Scaevola taccada, Diaporthe musigena on Musa sp., Diaporthe acaciigena on Acacia retinodes, Leptoxyphium kurandae on Eucalyptus sp., Neofusicoccum grevilleae on Grevillea aurea, Phytophthora fluvialis from water in native bushland, Pseudocercospora cyathicola on Cyathea australis, and Teratosphaeria mareebensis on Eucalyptus sp. Other species include Passalora leptophlebiae on Eucalyptus leptophlebia (Brazil), Exophiala tremulae on Populus tremuloides and Dictyosporium stellatum from submerged wood (Canada), Mycosphaerella valgourgensis on Yucca sp. (France), Sclerostagonospora cycadis on Cycas revoluta (Japan), Rachicladosporium pini on Pinus monophylla (Netherlands), Mycosphaerella wachendorfiae on Wachendorfia thyrsifolia and Diaporthe rhusicola on Rhus pendulina (South Africa). Novel genera of hyphomycetes include Noosia banksiae on Banksia aemula (Australia), Utrechtiana cibiessia on Phragmites australis (Netherlands), and Funbolia dimorpha on blackened stem bark of an unidentified tree (USA). Morphological and culture characteristics along with ITS DNA barcodes are provided for all taxa.

Microsatellite analysis indicates that Puccinia psidii in Australia is mutating but not recombining

Puccinia psidii is considered a biosecurity threat in Australia because of its broad host range that includes many species of Myrtaceae which dominate Australian ecosystems. Since it was first reported in this country, in April 2010, there has been little information about the population structure of the pathogen. In this study, six microsatellite loci were analysed to determine the genetic relationship among rust specimens from different hosts and locations in Australia, New Caledonia, Hawaii and China. The Chinese and New Caledonian specimens share a multi-locus genotype with the majority of the Australian specimens. The results also indicated a close relationship between Australian and Hawaiian samples. At present, the P. psidii population in Australia is genetically uniform with no evidence of sexual recombination. Five of the 104 collections varied by one allele at single loci, indicating that mutations are common but persistence of the mutants in the population may be less common.

The influence of pretreatment methods on saccharification of sugarcane bagasse by an enzyme extract from Chrysoporthe cubensis and commercial cocktails: A comparative study.

Biomass enzymatic hydrolysis depends on the pretreatment methods employed, the composition of initial feedstock and the enzyme cocktail used to release sugars for subsequent fermentation into ethanol. In this study, sugarcane bagasse was pretreated with 1% H2SO4 and 1% NaOH and the biomass saccharification was performed with 8% solids loading using 10 FPase units/g of bagasse of the enzymatic extract from Chrysoporthe cubensis and three commercial cocktails for a comparative study. Overall, the best glucose and xylose release was obtained from alkaline pretreated sugarcane bagasse. The C. cubensis extract promoted higher release of glucose (5.32 g/L) and xylose (9.00 g/L) than the commercial mixtures. Moreover, the C. cubensis extract presented high specific enzyme activities when compared to commercial cocktails mainly concerning to endoglucanase (331.84 U/mg of protein), β-glucosidase (29.48 U/mg of protein), β-xylosidase (2.95 U/mg of protein), pectinase (127.46 U/mg of protein) and laccase (2.49 U/mg of protein).

What is Scirrhia

The ascomycetous genus Scirrhia is presently treated as a member of Dothideomycetidae, though uncertainty remains as to which family it belongs in Capnodiales, Ascomycota. Recent collections on stems of a fern, Pteridium aquilinum (Dennstaedtiaceae) in Brazil, led to the discovery of a new species of Scirrhia, described here as S. brasiliensis. Based on DNA sequence data of the nuclear ribosomal DNA (LSU), Scirrhia is revealed to represent a member of Dothideomycetes, Capnodiales, Mycosphaerellaceae. Scirrhia is the first confirmed genus in Mycosphaerellaceae to have well developed pseudoparaphyses and a prominent hypostroma in which ascomata are arranged in parallel rows. Given the extremely slow growth rate and difficulty in obtaining cultures of S. brasiliensis on various growth media, it appears that Scirrhia represents a genus of potentially obligate plant pathogens within Mycosphaerellaceae.

A new species of Calonectria causing rot on ripe strawberry fruit in Brazil

A major problem in the strawberry production chain is the occurrence of fruit rot caused by fungi, thus, accurate identification of the pathogens associated with these rots is important for suitable management of diseases. During an assessment of postharvest diseases of strawberry plants, a rot caused by Calonectria was found. The surface of the infected fruits showed a slight leakage of liquid and the presence of mycelium with clearly defined hyphae containing a mass of conidiophores and conidia. Morphological examination was performed on isolates derived from single germinated conidium cultures, and phylogenetic analyses of four DNA loci (β-tubulin, histone H3, elongation factor and calmodulin) was undertaken. In order to confirm the pathogenicity, strawberry fruits and plants were dipped or sprayed with a conidial suspension. Strawberry fruits showed rot symptoms similar to those initially observed, and the plants developed leaf spot symptoms. The fungus was successfully reisolated from the infected tissues. Based on morphological and phylogenetic analysis, the fungus was shown to be distinct, and is described here as Calonectria fragariae sp. nov. This finding provides additional information for the better understanding of strawberry diseases in Brazil, enabling the development of more effective strategies of management of these diseases.

NEW PHYLOGENETIC LINEAGE OF Calonectria CAUSING LEAF BLIGHT IN Eucalyptus urophylla IN MATO GROSSO, BRAZIL

NOVA LINHAGEM FILOGENETICA DE Calonectria CAUSANDO MANCHA FOLIAR EM Eucalyptus urophylla EM MATO GROSSO A mancha-de-calonectria causada por Calonectria spp. e uma das principais doencas foliares da cultura do eucalipto no Brasil. Estudos recentes tem mostrado o potencial impacto dessa doenca e a enorme variabilidade existente na populacao do patogeno. No entanto nao ha estudos sobre ocorrencia e a identificacao de especies de Calonectria no estado de Mato Grosso. Assim, os objetivos desse trabalho foram fazer um levantamento das especies de Calonectria que ocorrem no sudeste de Mato Grosso e identificar por meio de analises de sequencia de DNA, quais especies sao predominantes. As analises filogeneticas foram realizadas com sequencias parciais dos genes fator de elongacao ( tef1a ), β-tubulina ( tub2 ), calmodulina ( cal ) e histona H3 ( his3 ). Foi observada uma grande variabilidade de Calonectria no estado de Mato Grosso, uma vez que foram encontrados diferentes grupos filogeneticos em isolados obtidos a partir de um unico local de coleta. Com base na analise filogenetica multi-genica, uma nova linhagem filogenetica e proposta ( Calonectria sp. new.), Calonectria pteridis e encontrada em Eucalyptus urophylla no Mato Grosso, e relata-se pela primeira vez no mundo a ocorrencia de Calonectria pseudometrosideri causando a mancha-de-calonectria em Eucalyptus spp. Palavras-chave: patologia florestal, Cylindrocladium , floresta plantada, mancha-foliar. ABSTRACT Calonectria-leaf-blight (CLB) caused by Calonectria spp. is one of the main foliar disease of eucalypt plantation in Brazil. Recent studies have shown the potential impact of this disease and the hyper-diversity in the pathogen population. However, there are no studies addressing the occurrence and identification of Calonectria species in Mato Grosso state, Brazil. The aims of this study were to conduct surveys of soils and trees in eucalypt plantation in southeast of Mato Grosso and identify which species are dominant by DNA sequence analyses. The phylogenetic analyses were performed by using partial sequences of translation elongation factor 1-α ( tef1a ), β-tubulin ( tub2 ), calmodulin ( cal ) and histone H3 ( his3 ) gene regions. A great variability in Calonectria was observed in the Mato Grosso state, since different phylogenetic groups were found in a survey from a single collection place. Based on multigene phylogenetic analyses, a new phylogenetic lineage is proposed ( Calonectria sp. new.), Calonectria pteridis is reported in Eucalyptus urophylla in Mato Grosso, and the occurrence of Calonectria pseudometrosideri causing CLB on Eucalyptus spp. is reported for the first time in the world. Keywords : forest pathology, Cylindrocladium , eucalyptus farming, planted forest. DOI: http://dx.doi.org/10.14583/2318-7670.v04n02a02