Occurrence of an endophytic, potentially pathogenic strain of Pseudomonas syringae in symptomless wild trees of Corylus avellana L

摘要

Fluorescent colonies were obtained from surface-sterilized twigs of healthy wild trees of Corylus avellana L. growing in central Italy. LOPAT, biochemical and pathogenicity tests, and 16S rDNA gene sequencing indicated that one endophytic isolate belonged to the Pseudomonas syringae species complex. This isolate incited hazelnut twig dieback only when inoculated at 1-2 x 10 super(7) CFU/ml per leaf scar. Lower doses did not induce symptoms. The isolate also caused necrosis in pear and lilac twigs, lemon fruits and bean pods. To our knowledge, this is the first report of an endophytic P. syringae strain obtained from wild C. avellana trees.