Evaluation of oleander accessions for resistance to Pseudomonas savastanoi pv. nerii

Nine oleander accessions were evaluated for resistance to Pseudomonas savastanoi pv. nerii, causal agent of the oleander knot disease. None of the accessions was resistant when tested with three bacterial strains of different virulence, but they varied significantly in the severity of symptoms induced by these strains. The most susceptible accessions "Dark Salmon" (dark salmon flower) showed deformation of stems, leaves and seed pods and secondary knots on aerial parts, whereas the least susceptible one "White" (white flower), inoculated with the least virulent strain, showed neither localized knots at the inoculation point nor secondary symptoms. In this study an in vitro test, based on prick inoculation of leaf segments, was optimised for use in pathogenicity tests or as an in vitro resistance screening test

A feasibility study of tomato fruit quality assessment and traceability by X-ray fluorescence spectroscopy and statistical analysis

X-ray fluorescence (XRF) measurements were performed on dried tomato samples coming from “Pachino district”, a geographical area recognized by the European Community with the “Protected Geographical Indication” (PGI) label. The purpose of this study is to establish a protocol for in-situ analysis in order to provide a fast and reliable technique for quality assessment and traceability of PGI products. Experimental data were studied by using Principal Component Analysis. The results show the presence of several characterizing elements, which establish a clear fingerprint pattern associated with the geographical origin of this product. Implications and perspectives in applying XRF analysis in order to disentangle tomato samples coming from different Sicilian geographical areas will be discussed

Lasiodiplodia species associated with dieback disease of mango (Mangifera indica) in Egypt

We constructed several multilocus DNA sequence datasets to assess the phylogenetic diversity of insecticolous fusaria, especially focusing on those housed at the Agricultural Research Service Collection of Entomopathogenic Fungi (ARSEF), and to aid molecular identifications of unknowns via the FUSARIUM-ID and Fusarium MLST online databases and analysis packages. Analyses of a 190-taxon, two-locus dataset, which included 159 isolates from insects, indicated that: (i) insect-associated fusaria were nested within 10 species complexes spanning the phylogenetic breadth of Fusarium, (ii) novel, putatively unnamed insecticolous species were nested within 8/10 species complexes and (iii) Latin binomials could be applied with confidence to only 18/58 phylogenetically distinct fusaria associated with pest insects. Phylogenetic analyses of an 82-taxon, three-locus dataset nearly fully resolved evolutionary relationships among the 10 clades containing insecticolous fusaria. Multilocus typing of isolates within four species complexes identified surprisingly high genetic diversity in that 63/65 of the fusaria typed represented newly discovered haplotypes. The DNA sequence data, together with corrected ABI sequence chromatograms and alignments, have been uploaded to the following websites dedicated to identifying fusaria: FUSARIUM-ID (http://isolate.fusariumdb.org) at Pennsylvania State University’s Department of Plant Pathology and Fusarium MLST (http://www.cbs.knaw.nl/fusarium) at the Centraalbureau voor Schimmelcultures (CBS-KNAW) Fungal Biodiversity Center