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A set of 493 old and local Spanish accessions of apple (Malus x domestica Borkh) maintained at three collections in Northeastern Spain was studied using 16 simple sequence repeats in order to estimate their genetic diversity and to identify the genetic structure and relationships among their accessions. An additional diverse set of 45 apple cultivars, including old Spanish and international cultivars, was added as reference. Genetic analyses performed by Bayesian model-based clustering revealed a very strong differentiation of two major groups. The first one clustered 159 individuals (52 % of unique genotypes) including local accessions and six old Spanish cultivars. The second major group was formed by 145 individuals, including 38 international reference cultivars and one old Spanish cultivar. Nested Bayesian clustering was applied to those two groups and two and four sub-groups were found at each one, respectively. The identification of private and unique alleles, and the remarkable differences in allelic richness among groups and sub-groups constitute further evidence of a clear genetic structure. The results obtained through the factorial correspondence and analyses of molecular variance confirmed those obtained by Bayesian analyses, revealing moderate but significant differentiation among the two major groups (F ST 00.076) and the six sub-groups (F ST 0 0.111). Our results highlight that the genetic diversity encompassed by currently cultivated apple accounts only for a small fraction of that existing within the species, and that an important part (≈60 %) of the local material analyzed constitutes a good example of genetic distinctness with respect to the main cultivars used in European orchards.

European plum (Prunus domestica L.) is an ancient domesticated species cultivated in temperate areas worldwide whose genetic structure has been scarcely analyzed to date. In this study, a broad representation of Spanish European plum germplasm collected in Northeastern Spain and a representative set of reference cultivars were compared using nuclear and chloroplast markers. The number of alleles per locus detected with the SSR markers ranged from 8 to 39, with an average of 23.4 alleles, and 8 haplotypes were identified. Bayesian model-based clustering, minimum spanning networks, and the analysis of molecular variance showed the existence of a hierarchical structure. At the first level, two genetic groups were found, one containing ‘Reine Claude’ type reference cultivars altogether with ca. 25% of local genotypes, and a second one much more diverse. This latter group split in two groups, one containing most (ca. 70%) local genotypes and some old Spanish and French reference cultivars, whereas the other included 24 reference cultivars and only six local genotypes. A third partition level allowed a significant finer delineation into five groups. As a whole, the genetic structure of European plum from Northeastern Spain was shown to be complex and conditioned by a geographical proximity factor. This study not only contributes to genetic conservation and breeding for this species at the national level, but also supports the relevance of undertaking similar tasks of collection and characterization in other unexplored areas. Moreover, this kind of research could lead to future coordinated actions for the examination of the whole European plum diversity, to define conservation strategies, and could be used to better understand the genetic control of traits of horticultural interest through association mapping.

Precision viticulture has been applied to date mainly at the field level, for which the ability of high resolution data to match within-field variability has been already shown. However, to be fully operational, it should also be applicable at the whole-vineyard scale. The aim of this study was to analyze whether it is possible to use precision viticulture tools to define meaningful management zones at the whole-vineyard scale. Experiments were carried out in year 2008 on 90 ha planted of cv. Tempranillo from a vineyard with a total area of 140 ha in Spain. A three-level classification was established at both scales using NDVI, elevation and soil apparent conductivity data. The agronomic significance of these classes was tested comparing the vegetative growth, yield, carbon discrimination isotopic ratio and berry quality observed at each class. The analysis of high resolution information has been proved to be relevant in order to define whole vineyard classes with agronomic implications, the spatial variability of the vineyard being structured.