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The ambitious idea for the development of new tablegrape seedless varieties, suitable for growing in the Mediterranean basin and highly competitive on the international markets, has recently led to the foundation (in 2015) of the Italian Variety Club (IVC) a network of 17 enterprises and 2 research Institutions in Southern Italy. This synergic collaboration among private companies and researchers aims to develop and transfer varietal and technical innovation to the growers and to strengthen the Italian table grape supply chain merging high quality products and sustainable agriculture. The breeding program is organized in different interconnected activities such as: "seed x seedless" varieties and "seedless x seedless" varieties controlled crosses, involving Apulian traditional genotypes and élite cultivars; F1seedling production with molecular marker assisted selection (MAS) for an early identification of seedless genotypes; in vitro embryo culture; plant evaluation under field conditions. In the coming years the activities of varietal description and official registration, Patent protection, and establishment of stock fields will be initiated. As result of the 3-year activities, the progenies of 75 "seed x seedless" varieties crosses, 28 "seedless x seedless" varieties crosses and 12 crosses involving germplasm with resistance traits have been obtained and analysed and the field evaluation begun. With regard to progenies derived from "seedless x seedless" varieties crosses, the average embryogenesis percentages (no. of germinated embryos/no. of cultivated ovules) was about 8-9%, varying according to the parents used. Following the extensive use of MAS about 40% of each "seed x seedless" varieties progeny carried allele associated to seedless locus. Actually about 6,000 new genotypes are grown in the first selection field, while further 6,000 seedless plants are going to be planted within 2018.

Osservazioni e rilievi di campo integrati da un programma di campionamenti e saggi diagnostici di laboratorio confermano in alcune delle varietà oggetto di studio una minore incidenza delle infezioni di Xylella fastidiosa, a cui sono associate sintomatologie di deperimento e manifestazioni di disseccamento più lievi e attenuate rispetto a quanto osservato in cultivar definite altamente suscettibili, ove la presenza di infezioni di X. fatidiosa compromette la sopravvivenza stessa delle piante. I risultati, oltre a confermare i fenomeni di resistenza già osservati in precedenti studi sulla cultivar Leccino, individuano nella selezione FS-17®, un ulteriore e potenziale fonte di resistenza al batterio. Al contrario, si rafforzano le evidenze sull’elevata suscettibilità delle cultivar Cellina di Nardo e Ogliarola salentina. Si presenta infine una rapida sintesi delle diverse attività in corso sulla ricerca di fonti di resistenza.

"Small RNAs were extracted and purified from total nucleic acids in late spring from two pooled samples of cv. Panse Precoce: ridge-like proliferations excised from symptomatic leaves, and symptomless portions. The sRNA libraries were sequenced using High Definition adapters. The resulting short reads were used to investigate the presence of viruses and for the analysis of host response Differentially expressed sRNAs between the two samples showed a prevalence of miRNA response. A down regulation of miR166 and miR396 in ena1 was observed. These miRNAs are involved in abaxial/adaxial identity of the leaf lamina and regulation of Growth-Regulating Factors genes implicated in the control of cell proliferation during leaf development "

Enation disease of the grapevine is an erratic disorder, whose symptoms recall a teratological condition possibly deriving from hormonal unbalance. Even though graft transmissibility of enations supports a viral aetiology of the disease, its putative agent has not yet been identified.

Deployment of resistant varieties is a key strategy for mitigating economic losses due to Xylella fastidiosa infections in crops, particularly in those areas where the bacterium finds favourable conditions for its persistence and infections are associated with severe diseases. As such, genetic traits that confer resistance/tolerance have been identified in the past in grapes, citrus and, more recently, in olives. Although understanding the molecular pathways involved in the resistance is a primary target of many studies, nowadays supported by the powerful resolution of the high-throughput sequencing technologies, biological confirmation remains a paramount tool to ultimately define the response of a given plant genotype. In this context, the emergence of X. fastidiosa in olives in southern Italy, prompted for large surveys and biological screening tests of olive germplasm in open fields and in greenhouses. Test plants are monitored for symptoms, incidence of bacterial infections, estimation of the bacterial population size and, more recently, analysed for the expression of LRR-RLKs- and ABA-related genes. The results so far collected highlighted the following aspects: (i) under controlled conditions the latent period of the infections in olives is as short as one year in the most susceptible cultivars, whereas under field conditions a first reliable estimation of the symptoms associated with the infections could be retrieved upon at least three years of exposure to the natural pressure of inoculum; (ii) cultivars under testing could be firstly distinguished in highly susceptible’ those that developed symptoms in the shortest time and those ‘potentially tolerant/resistant’ deserving further investigation; (iii) upon needle-inoculations or field exposure, cultivars could be differentiated based on the rate of systemic infections, as highly infected vs low-infected. Interestingly, several cultivars either in greenhouses or in field testing produced results similar to those recorded for the cultivar Leccino, used as resistant control; indeed cultivars harbouring high bacterial titers but not showing symptoms (i.e. with traits of tolerance) have also been identified. Although preliminary, these studies allowed to gather information on the spectrum of tolerance/resistance of additional olive cultivars.

The investigation on the genetic diversity of grapevine germplasm is crucial for a more efficient use of grapevine genetic resources in light of changing environmental conditions. Here, we used simple sequence repeats (SSRs) coupled with single nucleotide polymorphism (SNP) markers to disclose grapevine genetic diversity of a collection of Apulian minor/neglected genotypes. Their relationships with national or international cultivars were also examined. Genetic diversity was investigated using 10 SSR markers and 1,178 SNPs generated by genotyping by sequencing (GBS). Based on the SSR data, the 128 genotypes were classified into six main genetic clusters. Twenty-four putative cases of synonymy and 2 of misnamings were detected. Ten &ldquo, unknown&rdquo, autochthonous genotypes did not show high similarity to Apulian, national, or international varieties. We took advantage of available GBS-derived SNP data points for only forty genotypes to better investigate the genetic distance among them, identify private SNP alleles, and divergent loci putatively under selection. Based on SNP alleles, two interesting gene pools of minor/neglected Apulian samples were identified. Genetic divergence was investigated by FST and allowed the detection of loci capable of differentiating the gene pools. Overall, this work emphasizes the need for recovering the untapped genetic variability that characterizes minor/neglected grapevine Apulian genotypes and the requirement to preserve and use more efficiently grapevine genetic resources in breeding programs.