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During the 2012 and 2013 growing seasons, a disease was detected on potted laurustinus (Viburnum tinus) plants in two nurseries located in the Catania province (eastern Sicily, Italy). 'Cylindrocarpon'-like species were consistently recovered from crown rot and stem rot tissues. Based on morphological characteristics, DNA sequencing and phylogenetic analysis of β-tubulin (TUB), histone H3 (HIS3) and translation elongation factor-1α (TEF-1 α) gene sequences, the fungi associated with symptomatic tissues were identified as 'Cylindrocarpon' pauciseptatum, Ilyonectria novozelandica and I. torresensis. Koch's postulates were fulfilled by pathogenicity tests carried out on potted V. tinus cuttings. To our knowledge, this is the first report worldwide of 'C.' pauciseptatum, I. novozelandica and I. torresensis causing disease on V. tinus. [ABSTRACT FROM AUTHOR]

During 2013, a new root rot and leaf blight was detected on potted Pittosporum tenuifolium cv. 'Silver Queen' plants in a nursery located in the Catania province (eastern Sicily, Italy). On the basis of morphological and cultural features as well as internal transcribed spacer sequence data, the causal agent was identified as Pythium irregulare. Koch's postulates were fulfilled by pathogenicity tests carried out on potted P. tenuifolium cv. 'Silver Queen' plants. To our knowledge, this is the first detection of P. irregulare root rot and foliar blight disease on P. tenuifolium in Europe, and it is the first detection using molecular methods for this oomycete pathogen in Italy. [ABSTRACT FROM AUTHOR]

During the period from 2010 to 2013 preharvest symptoms were detected on different cultivars of sweet orange in six orchards in Catania, Siracusa and Enna provinces, Southern Italy. A total of 56 monosporic fungal isolates were obtained, and among these, 44 were identified as Colletotrichum gloeosporioides and 12 as C. karstii through morphological and molecular analysis. PCR with primers ITS1 and ITS4, primers TubGF1 and TubGR specific for β-tubulin gene, primers GDF-GDR, specific for Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene, were used to confirm the identification of Colletotrichum isolates from citrus. The ITS1-5.8S-ITS2 region, a portion of approximately 500 bp of β-tubulin gene and a fragment of 220 bp of GAPDH gene of the isolates were sequenced and analysed with the BLASTn program. Koch's postulates were fulfilled by pathogenicity tests carried out on fruit of 'Tarocco Scire' and 'Tarocco Nucellare' with representative isolates of C. gloeosporioides and C. karstii. Field surveys and pathogenicity tests revealed significant differences in fruit susceptibility between 'Tarocco Scire' and 'Tarocco Nucellare' and in virulence between the fungal species. To our knowledge, this is the first report on the emergence of Colletotrichum spp. causing anthracnose in preharvest conditions. [ABSTRACT FROM AUTHOR]

During the 2009 and the 2010 growing seasons, a root rot disease has been detected on young potted Persea americana plants in two nurseries located in the Catania and Messina provinces (eastern Sicily, Italy). A Cylindrocarpon sp. was consistently recovered from pieces of symptomatic tissues on Petri dishes containing potato dextrose agar. On the basis of morphological characteristics and molecular identification by DNA sequencing and phylogenetic analysis of internal transcribed spacer and β-tubulin gene regions, the causal agent was identified as Ilyonectria (= Neonectria) macrodidyma. Koch's postulates were fulfilled by pathogenicity tests carried out on potted P. americana seedlings. To our knowledge, this is the first to report worldwide of the occurrence of a disease caused by I. macrodidyma on P. americana. [ABSTRACT FROM AUTHOR]

Crown and root rot has been detected on potted Laurus nobilis plants in a nursery located in the Catania province (Italy). Perithecia referable to a Calonectria species were consistently detected on crowns and stems of symptomatic plants. Based on morphology, cultural features and molecular analysis, the species was identified as Calonectria ilicicola. Koch's postulates were fulfilled by pathogenicity tests carried out on potted Laurus nobilis seedlings. To our knowledge, this is the first report of the occurrence of a disease caused by Ca. ilicicola on Laurus nobilis. [ABSTRACT FROM AUTHOR]