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In several growing areas of Northern Italy cherry is affected by a severe decline that leads plants to die in two-weeks/one month maximum. From the beginning of the summer the affected plants show leaves of smaller size, with chlorosis, reddening, curling aspect and premature fall; young branches also show some lack of lignifications. Preliminary tests excluded presence of several biotic or abiotic agents; to verify the possible phytoplasma association with the disease nucleic acid extraction was performed from leaf midribs as well as from phloem scrapes of trunks from declining trees. Molecular analyses carried out on samples from declining cherry plants collected in different orchards from 2002 to 2004 allowed identification of phytoplasmas belonging to different ribosomal subgroups such as 16SrV-B; 16SrIII-B and 16SrXII-A (stolbur). Since the area monitored was limited and phytoplasma detection was achieved in both hilly and sandy soil locations on plants usually older than 5–6 years, it appears possible that infection was related to the health status of propagation material employed for plantations.

A vine decline of kiwifruit (A. deliciosa ‘Hayward’) was observed in 2012 and 2013 in about 600 ha in the province of Verona (Northern Italy). During the last two years, a progressive vine decline took place during summers with high temperatures (over 35°C) requiring copious furrow irrigation, and with mild temperatures and abundant rainfall during winter and spring that caused long periods of soil waterlogging. The diseased plants died after a gradual blight of the leaves. Rotting of the roots intermediate in diameter and of the distal rootlets were associated with all cases of decline. Phytophthora and Pythium species were isolated from the decayed roots, were plate purified and identified by sequence analysis of the internal transcribed spacer (ITS) region of the rDNA amplified with specific primers. Pathogenicity of the Phytophthora isolates was verified with experimental inoculations of kiwi plantlets. Typical symptoms of the decline in the leaves were caused by isolates of Phytophthora cryptogea. This is the first report of Phytophthora and Pythium presence in plants with root rot and vine decline of kiwifruit in Northern Italy associated to anomalous climate condition.

Two genera of the Fabaceae family showed phytoplasmas symptoms in different locations in Europe i.e. Germany and Italy. Spartium junceum L. (Spanish broom) is a deciduous shrub with dark green, round stems and alternate leaves; inflorescences are terminal clusters of several bright yellow somewhat fragrant flowers. This ornamental shrub is frequently spontaneously growing especially in southern Italy where it is affected by spartium witches’ broom (SpaWB) disease, characterized by proliferation of axillary buds and stem fasciation. Two different phytoplasmas have been associated to SpaWB: ‘Candidatus Phytoplasma spartii’ (group 16SrX-D) and a phytoplasma belonging to elm yellows group (16SrV-C). Both were reported associated with SpaWB in Italy while only ‘Ca. P. spartii’ was reported in Spain. In the spring of 2011, typical SpaWB symptoms were observed in a plant up to 2 m tall growing in the city of Ercolano (Campania region, Italy). A similar symptomatology was observed in a group of shrubs of Cytisus scoparius (L) syn. Sarothamnus scoparius, better known as common broom or scotch broom growing in Dahlem botanical garden in Berlin (Germany). This is a perennial shrub native to western and central Europe, but it is considered invasive plant in areas such as North America and New Zealand. Symptomatic and asymptomatic samples were collected in both cases: five samples of C. scoparius and two of S. junceum were analysed for phytoplasma presence by nested-PCR assays employing primer pairs P1A/P7A followed by F1/B6 and R16F2n/R2, phytoplasma identification was achieved by RFLP analyses with Tru1I on the two latter amplicons. Further confirmation of phytoplasma identity was achieved by nested-PCR assays with primers specific for phytoplasma groups 16SrI, 16SrV and 16SrX. All symptomatic samples produced amplicons of the expected lengths and no product was amplified from asymptomatic plants and using 16SrV specific primers. Identification and classification of phytoplasmas allow to detect ‘Ca. P. spartii’ subgroup 16SrX-D and ‘Ca. P. asteris’ subgroup 16SrI-B in both genera. In some of the samples of C. scoparius also stolbur phytoplasmas were identified. Further phytoplasma characterization was carried out on tuf gene using a cocktail primers mix that was able to amplify phytoplasmas identified as ‘Ca. P. asteris’ in S. junceum and phytoplasmas showing two different Tru1I profiles in C. scoparius from Germany that are not present in any published RFLP profile on this gene. Direct amplicon sequencing is in progress in order to verify possible affiliation to ‘Ca. P. spartii’ group since the only available sequences of this gene on phytoplasmas are deposited in Qbank since they were obtained from the Qbol EU project.

During 2003–2005 extensive surveys were carried out in diverse location in Serbia to verify phytoplasma presence in fruit trees species affected by decline, reddening, yellowing or witches’ broom symptoms. Tests were carried out using PCR/RFLP analyses to detect phytoplasma presence and to determine their identity. European stone fruit yellows phytoplasmas (16SrX-B) were identified in apricot plants showing typical chlorotic leaf roll symptoms and in samples collected from peach plants showing general decline together with yellowing and reddening of leaves. In other samples from peaches with similar symptoms, stolbur (16SrXII-A) phytoplasmas were detected. Two different symptoms were associated with diverse phytoplasmas in pear: pear decline (16SrX-C) phytoplasmas were identified in samples from plants showing typical decline symptoms, while X-disease (16SrIII-B) phytoplasmas were identified in a pear plant showing witches’ broom and reduced growth. Samples from apple showing symptoms of proliferation, witches’ broom and reduced fruit size, resulted to be infected by apple proliferation (16SrX-A) phytoplasmas.