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Collections of deletion mutants are important tools for functional genomics in crops. In order to establish an efficient physical gamma-ray-based mutagenesis protocol and estimate the frequency of induced chromosome deletion events in apple, we mutagenized a total of 338 leaves of the apple cultivar 'Golden Delicious' with a range of irradiation doses (from 0 to 30 Gy). After in vitro culture and regeneration, a total of 248 plantlets were genotyped by a custom-made 384 SNP-based array suited to identify homozygous regions, corresponding to chromosome deletions produced by the irradiation and/or the in vitro culture treatments. With this approach, we identified nine multi-SNP chromosome deletions corresponding to 3.7 % of all regenerated plantlets and ranging from one to 44 cM (0.1-20.2 Mb). Chromosome deletions were also observed at mildly, not significantly lower frequency in plantlets regenerated from non-irradiated leaves. Our results confirm the possibility to generate apple plants with sizeable deletions of known dimension and location, opening the way to creating a collection of deletions spanning the apple genome useful for functional genomics. The high frequency of deletions apparently caused by somaclonal variation deserves further investigation.

A reliable elevated eating quality is a prerequisite for consumer satisfaction and for motivating loyalty to a pear cultivar and a mark of origin. Fruit quality is determined by a number of factors such as growing conditions, harvesting operation, storage and shelf life. A study was conducted on 'Abate Fetel' to investigate the effect of production systems and harvest date on eating quality. A quantitative descriptive analysis (QDA), test was conducted to define sensorial profiles of fruits before consumer testing. In the same period, over 200 consumers were contacted in shopping malls and asked to taste fresh-cut peeled slices of the six treatments and for each rate 'sweetness', 'pear aroma' and 'overall liking' on a scale from I (dislike extremely), to 9 (like extremely). More than 60% of consumers rated 'acceptance' of slices of four of the treatments with votes between 6 and 9 while the other two, different for harvest date, but deriving from the same production system received more than 40% of votes between 1 and 3. Panel test results showed how a production system influences pear eating attributes and consumer tests showed how these differences can be perceived by normal consumers. A reasoned plan of sensory tests could provide useful information to be spent in monitoring production and enhancing quality of pears.

The high competitiveness in agricultural markets has generated saturation; this situation implies a constant search of innovations to achieve a better commercial performance of agricultural companies. In this sense, to improve the competitiveness of agricultural products, it is basic to know the final demand of them, wich in this case are focused in fresh apricots. Considering this, the main objective of this research is to contribute to fresh apricot industry improvement in the national and international market, through a better knowledge in customer behaviour that could be attractive and promissory for this industry both in Chile and Italy. To achieve this aim, a survey has been applied to a non probabilistic sample of Chilean and Italian consumers, and later the information has been analyzed by multivariant methods, specifically, factorial analysis, cluster and joint. In this sense, this study centres on the scientific analysis of fresh apricots consumers, in the Chilean and Italian market. In this study, the variables related to descriptive aspects of consumption, demographics characteristics, attitudes and preferences in general to the Chilean apricots were analyzed. In relation to the principal results of this study, a preference to the Chilean apricots was observed, specifically in cultivar “Robada” compared to “Castle Brite”, both in national and international market

In vitro shoots of six pear (Pyrus communis L.) cultivars, Conference, Doyenné d'Hiver, Passe Crassane, Bartlett, Abbé Fetel and Butirra Precoce Morettini were irradiated with gamma rays (3.5 Gy). After three subcultures, microcuttings from the irradiated shoots and from additional non-irradiated microcuttings were rooted to establish plants for survey orchards. All trees were individually observed for variation in fruit traits and for productivity. Trees were selected for improved characters related to production such as early bearing and consistent productivity. Variations observed in fruit appearance concerned degree of russeting, fruit shape and size. The frequencies of the observed variations in fruit traits depended on the cultivar, ranging from 0.81% in Doyenné d'Hiver to 3.64% in Passe Crassane. Of the 97 variants selected, only two showed chimeral behavior.

Promising new tools for peach fruit quality breeding have been revised in this work. These tools included fruit quality evaluation through physical, chemical and sensorial parameters and post-harvest storage evaluation. The development of a feasible method for an early testing of peach selections generated in breeding programs is also well described together with the discussion of the inheritance of the main fruit quality traits in peach. In addition, non-destructive evaluation methods such as near-infrared, electronic nose and non-destructive impact response were revised. Finally several strategies for the development of molecular marker associated to fruit traits were also revised. Methodologies for the analysis of marker-assisted selection include the use of mapping populations segregating for desired characters. To date, twenty five monogenic genes and QTLs have been mapped in different peach genetic linkage maps. Other markers being used included expressed sequences tags (ESTs) cloned gene analogs (CGAs) and single point mutations (single nucleotide polymorphisms, SNPs). More recent efforts are being oriented to the elaboration of physical maps and the complete sequencing of the peach genome.