1,720,980 research outputs found
Influence of pruning wood management and suckering on Scaphoideus titanus Ball density in two distinct wine-growing area
No full textControllo del Ragnetto Giallo della Vite (Eotetranychus Carpini F. Vitis) attraverso l’immissione dell’acaro fitoseide Kampimodromus Aberrans
No full textNel presente lavoro si riportano le esperienze di tre anni di controllo del ragnetto giallo della vite (Eotetranychus carpini f. vitis) tramite l'immissione dell’acaro fitoseide Kampimodromus aberrans in Valdadige (VR). Questa tecnica di controllo biologico aumentativo è stata applicata prelevando a fine inverno da un "vigneto donatore", tralci di potatura con elevata presenza di femmine fecondate dell’acaro predatore, che sono stati trasferiti in "vigneti accettori" dove negli anni precedenti era stata osservata una infestazione dell’acaro fitofago. I risultati evidenziano l'efficacia dei rilasci di K. aberrans nel ripristinare velocemente l'equilibrio tra acari dannosi e acari predatori in caso che esso sia stato compromesso da strategie di difesa poco rispettose degli artropodi utili. Nell’elaborato vengono presentati e discussi i metodi e le densità di rilascio più efficaci
Efficacy of biopesticides against Scaphoideus titanus Ball in different experimental conditions
No full textImpiego di Emamectina in strategie di difesa ai principali carpofagi e selettività nei confronti degli acari fitoseidi
No full textKampimodromus aberrans contro il ragnetto giallo della vite
No full textIl contenimento naturale di ragnetto giallo della vite con l’introduzione dell’acaro fitoseide predatore è stato efficace – in modo proporzionale alla densità dei rilasci – a partire dal germogliamento e per tutta la stagione. Per mantenere un’adeguata presenza di fitoseidi è importante la scelta dei prodotti fitosanitari, in particolare contro Scaphoideus titanus, vettore della flavescenza dorata della vite
Identification of epidemic “flavescence dorée” molecular variants in Emilia-Romagna and Veneto regions
No full textThe study of the genetic variability of phytoplasmas is a fundamental tool to clarify their epidemiology and to implement an effective monitoring and management of their associated diseases. “Flavescence dorée” (FD), a threatening disease of grapevine associated to phytoplasmas, is distributed within the most important European wine-producing areas, and has severe effects on both vineyard productivity and landscape management. FD is a quarantine disease in Europe, mainly transmitted by the ampelophagous leafhopper Scaphoideus titanus and, despite the efforts to contain the pathogen dissemination, the disease is still epidemic in several viticultural areas of Northern Italy. Based on sequence and restriction fragment length polymorphism (RFLP) analysis of the 16S rRNA gene two FD ribosomal groups were described as present in Italy during the last century: 16SrV-C and 16SrV-D. However, the sequencing of non-ribosomal loci, such as secY, map and rpsC, allowed the identification over the years of several variants within the FD phytoplasma populations. A multilocus analysis approach was carried out on symptomatic FD-infected samples collected in Emilia-Romagna and Veneto regions, in different areas where the disease is spreading in the last 2-3 years. The geographic distribution of the two strains was confirmed to be different, with areas (Treviso province) with the prevalence of FD-C and others (Verona and Modena provinces) with only FD-D strains presence. Interestingly, FD-D phytoplasmas were identified for the first time also in a vineyard located in Modigliana (Forlì-Cesena province) and surrounded by forests. The molecular analyses allowed the identification of genetic variants among FD-D populations in both regions, that is quite a novel finding for these phytoplasmas that showed since their first identification in 1996 very little variability. In particular, the sequencing of secY amplicons highlighted the presence of the same SNP variation in samples of cultivars Teroldego and Trebbiano collected in Verona province and in grapevines cv Sangiovese located in Modigliana (Forlì-Cesena province). On the other hand, among FD-C phytoplasma strains, the highest variability was shown on rpsC gene, that highlighted 5 restriction profiles after RFLP analyses on samples cv Glera collected in Treviso and Belluno provinces. These findings suggest that the epidemiology of the disease is still to be monitored and is now involving different vectors/plant hosts species that are very likely responsible for the emergence of these FD variants. Therefore, a continuous and capillary monitoring of the FD strains associated with disease on the areas where it is present is necessary for application of the most appropriate and stringent controlling measures aimed to avoid the epidemic spreading of these emerging pathogenic variant strains
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