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23rd European Photovoltaic Solar Energy Conference and Exhibition, 1-5 September 2008, Valencia, Spain; 2634-2636, CuIn1-xAlxSe2 (CIAS) thin films were grown by a two stage process. Cu, In and Al layers were sequentially evaporated and subsequently heated with elemental selenium in a quasi-closed graphite box. Different x values (x>0.4) were obtained by varying the Al and In precursor layers thicknesses. Selenization conditions such as Se amount provided during the selenization process were adjusted in order to optimize the film properties. Polycrystalline CuIn1-XAlXSe2 thin films with chalcopyrite structure were obtained. Referred to CuInSe2 thin films the lattice parameters, the (112) orientation and the average crystallite size decreased and the band gap energy increased with increasing Al content. The incorporation of Al changed the thin film morphology towards smaller grain sizes and an open structure less dense. The ternary compound CuAlSe2 was formed in isolated areas and some samples showed coexistence of CuInSe2 and CuIn1-xAlxSe2 phases.

Extensive survey to detect and identify phytoplasmas associated with Chilean grapevines was performed from 2003 to 2005 sampling symptomatic or asymptomatic grapevine plants. Nested PCR amplification allow the detection of phytoplasmas in 28 out of 90 samples. RFLP analyses identified phytoplasmas as belonging to ribosomal subgroups 16SrI-B, 16SrI-C, 16SrVII-A and 16SrXII-A. Cloning and sequencing of selected strains allow to detect genetic variability in 16SrXII-A strains.

Myrtus communis is a bushy species of the Mediterranean area that produce very popular liquor: Red mirto and White mirto. Preliminary studies in North Sardinia, resulted in the observation of a severe symptomatology associated with phytoplasma presence. These studies continued, and recently a total of 33 symptomatic plants belonging to different cultivars in two plantations were mapped and repeatedly tested using molecular methods. Phytoplasmas belonging to the 16SrI, 16SrII-F, 16SrIII, 16SrV-A, 16SrX-A, and 16SrXII-A subgroups were identified. Molecular assays on potential insect vectors showed that 16SrX-A+16SrI-B, 16SrXII-A and 16SrIII subgroups were present.

The reorganization of the morphologically complex amorphous carbon nanoparticle layers deposited on a Si substrate into ordered sp2 entities was investigated by means of two complementary techniques, synchrotron radiation x-ray photoelectron microscopy and scanning electron microscopy, which provided the necessary chemical and structural information at submicrometer length scales. The studies were focused on the effect of the local thickness of the carbon nanoparticle layer on the extent of the restructuring process. The lateral distribution of the phases formed on the surface and their local chemical configuration were revealed by measuring C 1s and the Si 2p core level spectra with photoelectron spectromicroscopy. The results showed that an effective graphitization, which on the basis of complementary characterization techniques was associated to the formation of single-wall nanotubes, occurs only in areas with a high density of nanoparticles. These findings indicate that tube self-assembling is promoted by the interaction between neighboring nanoparticles.

[EN]Since 1999 witches' broom and decline diseases have been observed in Spartium junceum, bom spontaneous and ornamental shrubs located in urban areas, in all the seaside regions of Catalonia (Northeastern Spain). The symptoms may affect the whole plant or few branches. The witches' broom developed from axillar buds is the most important symptom. Affected plants end up turning very dry, and eventually die in a few years. These symptoms have been recently associated in Italy to the presence of apple proliferation phytoplasma group. In this work the molecular methods (nested PCR, RFLP and sequencing) that allow the characterization of the phytoplasmas detected in symptomatic Spanish Broom shrubs from Catalunya are described. The phytoplasmas detected are molecularly undistinguishable from others of the 16SrX group (apple proliferation),subgroup D. [ES]Desde hace 4 años, se ha observado, en toda la franja costera de Cataluña, que arbustos de Spartium junceum, tanto espontáneos como ornamentales, presentan una enfermedad caracterizada por formaciones en escobas de bruja y decaimiento. Los síntomas pueden afectar a la totalidad de la planta o sólo a algunas ramas. El síntoma de mayor importancia es la escoba de bruja que se desarrolla a partir de la yema axilar. Las plantas afectadas se secan y, en ocasiones, mueren en pocos años. Recientemente, en Italia se han asociado estos síntomas a la presencia de fitoplasmas del grupo "Apple proliferation". En este trabajo se describen los métodos moleculares ("nested" PCR, RFLP y secuenciación) que han permitido caracterizar los fitoplasmas detectados en arbustos de retama sintomáticos en Cataluña. Los fitoplasmas detectados en 5. junceum de España son molecularmente indistinguibles de otros fitoplasmas del grupo 16SrX ("apple proliferation")y pertenecen al subgrupo D.

[EN]Since 1999 witches' broom and decline diseases have been observed in Spartium junceum, bom spontaneous and ornamental shrubs located in urban areas, in all the seaside regions of Catalonia (Northeastern Spain). The symptoms may affect the whole plant or few branches. The witches' broom developed from axillar buds is the most important symptom. Affected plants end up turning very dry, and eventually die in a few years. These symptoms have been recently associated in Italy to the presence of apple proliferation phytoplasma group. In this work the molecular methods (nested PCR, RFLP and sequencing) that allow the characterization of the phytoplasmas detected in symptomatic Spanish Broom shrubs from Catalunya are described. The phytoplasmas detected are molecularly undistinguishable from others of the 16SrX group (apple proliferation),subgroup D., [ES]Desde hace 4 años, se ha observado, en toda la franja costera de Cataluña, que arbustos de Spartium junceum, tanto espontáneos como ornamentales, presentan una enfermedad caracterizada por formaciones en escobas de bruja y decaimiento. Los síntomas pueden afectar a la totalidad de la planta o sólo a algunas ramas. El síntoma de mayor importancia es la escoba de bruja que se desarrolla a partir de la yema axilar. Las plantas afectadas se secan y, en ocasiones, mueren en pocos años. Recientemente, en Italia se han asociado estos síntomas a la presencia de fitoplasmas del grupo "Apple proliferation". En este trabajo se describen los métodos moleculares ("nested" PCR, RFLP y secuenciación) que han permitido caracterizar los fitoplasmas detectados en arbustos de retama sintomáticos en Cataluña. Los fitoplasmas detectados en 5. junceum de España son molecularmente indistinguibles de otros fitoplasmas del grupo 16SrX ("apple proliferation")y pertenecen al subgrupo D.

Flavescence doree is a devastating disease of grapevine widespread in several countries in EU such as France, Italy and Spain. Genetic variability among 17 Italian and 3 French FD strains was investigated by RFLP analyses based on a fragment of the ribosomal protein operon and on the non-ribosomal DNA fragment FD9. RFLP analysis of the PCR amplified ribosomal protein fragment/ coding for the 3' end of rpl22 and the entire rps3 genes, differentiated 4 rp-subgroups among the FD strains and 4 subgroups among the reference strains belonging to elm yellows group (16SrV). Sequencing and phylogenetic analysis of the same ribosomal protein DNA fragment validated the delineation of 4 distinct FD strain types derived by RFLP analyses. The results supported the differentiation based on analysis of the non-ribosomal DNA fragment FD9. The phylogenetic analysis further revealed relationships and a probable evolutionary trend among the FD strains and the other representatives of elm yellows group. All the FD strains together with the reference strains ALY, RuS and JWB formed a cluster very well distinct from the EY/ULW cluster. Moreover, ALY was shown to be more closely related to three FD strain types: the Lombardia/Piemonte, the French FD70, and the French FD88/ltalian FD-D strain clusters.