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La sana alimentazione e la ricerca di novel food possono contribuire ad una terza età in buona salute

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.

The peach melting flesh cultivars 'Ryan Sun' and 'Sweet September' and the non-melting, 'Kakamas' wereharvested according to their visually assessed ground color and divided into four, ripeness classes (M1,M2, M3, and M4). The following aspects were determined: fruit mass, soluble, solids content (SSC), groundskin hue angle (ho) and chroma (C*), the absorbance difference at 670 nm and, 720 nm index (IAD), andthe texture (fruit firmness measured with a needle, flesh firmness measured, with a 7.9 mm plunger,and uniaxial compression strength). Considering that in peaches, the hoof the, ground color and the IADare maturity indicators closely associated with ripeness and particularly with, flesh firmness, the textureparameters and their relationship to hoand IADwere examined. The visual, assessment of the groundcolor was validated as the criterion for sorting the ripeness levels in peaches, as confirmed by hoand IAD.Fruit firmness assessed with the needle and that with the 7.9 mm plunger, were highly correlated witheach other and with the hoand IAD, whereas the compression strength, exhibited less correlation withthe optical properties of the skin. The non-melting 'Kakamas' showed, the poorest correlation betweentexture and hoand IAD. Comparing both optical properties, the IAD, showed a higher correlation withtexture features than the ho. In a second experiment, fruit from the M3 ripeness class was maintained ina ripening chamber (20oC, and 80% RH) until the flesh was softened for consumption. During postharvest,the first two principal, components of a principal component analysis explained 85% of the total varianceof the texture, components and the optical properties of the skin. PC1 (67.2%) was defined positively by thetexture, parameters and IAD. The hoof the ground color was negatively related to all texture parameters,and, IAD. PC2 (17.8%) was associated positively with the juice content, and this parameter proved to be,independent of all others.

The quality requirements that consumers consider in their decision to purchase fresh fruit have garnered a great deal of attention from the actors in the fresh fruit productivity chain. This study seeks to identify attributes that could explain how a consumer of fresh peaches perceives quality. The focus on the peach was because of the limited knowledge of the signs of quality that the consumer is seeking in this fruit. As a result, the objective was to produce a model that explains the perception of the quality of fresh peaches by Spanish consumers. A theoretical model was created that explains quality using a set of intrinsic and extrinsic attributes. The information was from a survey of closed questions administered in person to a non-probabilistic sample of 192 Spanish consumers. The methodology used was structural equation modeling, with an analysis for goodness of fit using the indicators CMIN/ DF, RMR, NFI, RFI, RMSEA, and HOELTER. Thus, by adjusting the values recommended by the literature, a model was identified that explains the quality decisions of the consumers studied using two sets of attributes: intrinsic and extrinsic. Finally, significant and strong relationships were established between the perceived quality and the homogeneity of the fruit and between the perceived quality and the availability in supermarkets and fruit stores

CL; International audience; The success of any in vitro mutagenesis programme depends on the establishment of reproducible in vitro plant regeneration procedures, optimization of mutagenic treatments, and efficient screening of the mutagenized populations for desired variations (Ahloowalia, 1998; van Harten et al., 1998; Jain, 2000, 2006, 2007). Cell and tissue culture techniques can improve effectiveness of mutation induction in several aspects. One of the major advantages of tissue culture is that a large number of regenerated plants can be handled at ease for mutagenic treatments (Jain, 2000; Predrieri, 2001). They offer a wide choice of plant material for mutagen treatment (in vitro axillary buds, organs, tissues, protoplasts, and cells) (Broertjes and van Harten, 1988; Constabel and Shyluk, 1994; Jain and Newton, 1989; Duncan, 1997) that is more suited to mutation induction techniques as compared to in vivo buds (Predrieri, 2001). The tissue structures from which plants originate are either multicellular or of single cell origin (Williams and Maheshwaran, 1986; Ochatt et al., 2005; Kulkarni et al., 2007). Normally chimeras are major problems in regenerated plants by mutagen treatment of multicellular structures such as shoot tips or axillary buds. By in vitro culture chimeras can easily be dissociated by several time subcultures of shoot cultures, say 4 generations M1V4 (Jain, 2000; Predrieri, 2001) This, as compared to in vivo buds, means less risk of obtaining chimera plants and a higher probability for mutated cells to express the mutation in the phenotype (Broertjes and van Harten, 1988). It also facilitates rapid completion of the propagation cycles of subculture aimed to separate mutated from nonmutated sectors (Ahloowalia, 1998). In vitro selection and cloning of selected mutants can also be effective when supported by adequate early evaluation tools (Ball, 1990; Duncan, 1997; Ochatt, 2006; Ochatt et al., 2005) as well large scale multiplication of mutant plants. Micropropagation is an ideal system for true-totype multiplication of mutant plants by using shoot tips or axillary buds (Ahloowalia, 1998). Furthermore, tissue culture provides high phytosanitary conditions, which is an ideal system for obtaining healthy starting material and is maintained throughout the plant regeneration process (Ochatt et al., 1990; Cassels, 1998; Predrieri, 2001; Kulkarni et al., 2007). Therefore, in vitro mutagenesis should always be carried out on healthy explants. Otherwise endogenous contamination may compromise obtaining mutations, as well as selection and/or the survival of mutants.