Large scale genome assemblies of Magnaporthe oryzae rice isolates from Italy

We report long-range sequencing of nine rice-infecting Magnaporthe oryzae isolates from different rice-growing regions of Italy using Oxford Nanopore Technology. We aquired chromosome-level genome assemblies, polished with Illumina short reads, and removed mitochondrial sequences to improve the quality of the assemblies.We provide the genome assemblies to the public with open access

Mycobiota associated with the rhodophyte alien species Asparagopsis taxiformis (Delile) Trevisan de Saint-Leon in the Mediterranean Sea

This study is the first to investigate and characterize the mycobiota associated with the alien species Asparagopsis taxiformis, a rhodophyte classified as one of the ‘100 worst invasive species’ in the Mediterranean Sea by the Hellenic Center for Marine Research, as it threatens biodiversity. Fungal endophyte and epiphyte communities were investigated on algal specimens from two sampling sites on the island of Linosa (Marine Protected Area Isole Pelagie, Italy). 87% of the 24 specimens that were analysed for epiphytes displayed a microfungal colonization. No endophytes were found. Only a small amount of microfungi was found to be associated with this alga. Only five fungal taxa were isolated; two of which are sporadically associated with the alga, while three, Eurotium rubrum, Cladosporium cladosporioides and Cladosporium pseudocladosporioides, seem to be related to A. taxiformis. This scarcity could be related to algal chemical composition

Sink or swim: Updated knowledge on marine fungi associated with wood substrates in the Mediterranean Sea and hints about their potential to remediate hydrocarbons

This paper provides the first update in more than twenty years on the available knowledge about lignicolous marine fungi in the Mediterranean Sea. Fungi found on collected wood samples were analyzed using a combination of morphological and molecular techniques. Almost 90% of the samples were colonized by fungi. The total number of recorded taxa, which amounted to 57 in the late 1990s, has now risen to 93. Wood-inhabiting marine fungi are good producers of ligninolytic enzymes, which can degrade several aromatic and recalcitrant environmental pollutants. In light of bioremediation technologies, this study also evaluated the potential of the isolated strains to remediate complex ydrocarbon substrates. Seventeen isolates were shown to be able to grow on hydrocarbon media as a sole carbon source; enhanced performances were achieved in the presence of NaCl, suggesting that these fungi adapt well to marine conditions and confirming that salt can trigger specific metabolic pathways in marine fungi

Genetic Structure of Pyricularia grisea (Cooke) Sacc. Isolates from Italian Paddy Fields

Rice blast disease, caused by the fungus Pyricularia grisea (Cooke) Sacc., is responsible for considerable damages in rice crops in Italy and in other parts of the world. This study was conducted in order to investigate the genetic structure of a P. grisea population in the Po area, the largest rice area in Italy. Rice leaves showing blast symptoms were collected in three successive years (1998–2000) and 43 P. grisea monoconidial culture samples were isolated from infected rice leaves. Fungal DNAs were obtained from mycelia. Moreover, six additional P. grisea DNA samples representative for the five characterized European lineages were also investigated. All 49 DNAs were fingerprinted using the Pot2-based repetitive polymerase chain reaction specific for the blast pathogen. Unweighted pair-group method with arithmetic averages cluster analysis shows the presence of three main Italian lineages. Within lineages, similarity was higher than 80%. Samples representative of the three of five known European lineages grouped within these three Italian lineages confirming the presence of three European lineages in Italy. Furthermore, cluster analysis shows the presence of two new haplotypes never found before in the Italian lineage

A model of co-occurrence: segregation and aggregation patterns in the mycoflora of the crayfish Procambarus clarkii in Lake Trasimeno (central Italy)

Although attention on crayfish diseases has recently proliferated, the focus is mainly on a single host-parasite relationship rather than analyzing the entire mycoflora, probably due to the fact that (1) some diseases are occasional (pathogens of which are of difficult collection) and (2) economic impact is more relevant in aquaculture (i.e., a controlled environment where only few parasites occur) than in natural conditions. Contrary to this viewpoint, fungal ectoparasites assume a great importance since they are integral components in shaping community, ecosystem structure, and energy flow. Here we described the fungal species co-occurrence patterns (species segregation/ aggregation) using null models comparing the occurrence frequencies of ectosymbiots through host individuals with those expected by chance. Non-indigenous crayfish species like Procambarus clarkii allow to observe phenomena of competitive exclusion (segregation) or mutualism (aggregation) amongst fungi. We analyzed the fungal species occurrence on 86 host crayfish monthly collected from June 2007 to June 2008 in the Lake Trasimeno (Central Italy). A total of 29 fungal taxa were detected. Taxa showed a particular fungal assemblage with a great species variation depending on sampling month and crayfish sex, size, and body region. In particular, fungal species showed different occurrence patterns in both richness and segregation/ aggregation. The fungal community shows a non-random structure not in all cases, with the majority of tests indicating segregation, not aggregation of ectosymbiontic species on hosts. The non-random patterns of fungal co-occurrence in some cases suggest that some temporally or spatially variable factors are responsible for the establishment of the mycoflora community assemblage. We also detected temporal differences in fungal co-occurrences patterns. Regarding seasonal samples, the same analyses showed a competitive structure only in the sub-communities found on pleopodal coxae. In addition, analyses considering crayfish dimension evidenced non-random co-occurrence patterns only in crayfish hosts with a cephalothorax length larger than 45 mm. Our results demonstrated that, depending on sampling month and crayfish sex, size, and body region, well structured fungal assemblages on crayfish hosts can alternate with random fungal assemblages. Whenever non-randomness of fungal co-occurrence was detected, it hinted segregation, suggesting the lack of co-evolutive phenomena of mutualism, and favoring a competitive exclusion among the mycoflora species