High value late season peach cultivars from the region of Aragón (NE, Spain) are appreciated for their delicate flavor, external uniform golden appearance, yellow pulp and chiefly to be free of chemicals as they are bagged from their last three months of growth until harvest. However, their shelf life under storage is very short due to several problems such as loss of firmness, appearance of chilling injuries, incidence of physiological alterations called vitrescent dark spot (VDS) or corky spot (CS) and fungal rots. The research team from Zaragoza has worked for years in the fight against calcium-related physiological disorders in apples by preharvest strategies of foliar calcium treatments. More recently, postharvest treatments with low oxygen at room temperature (LOT) have been successfully applied. However, no reports of these kinds of treatments have been previously reported in late season peaches. Therefore, immediately after harvest, 'Chato' peaches were stored for 2 days at 20 °C under low O2 (1-2 %) in Palliflex bags. Thereafter, fruits were cold-stored (0-2 °C) without bag for 40 days and changes were monitored in terms of fruit quality, chilling injuries, incidence of physiological alterations and respiration rates. After 40 days of cold storage, the firmness of treated fruits was the same as at the harvest day, about 41.9 N, meanwhile fruits untreated, decreased to 35.0 N. On the other hand, LOT treatment decrease both the incidence of VDS from 37.9 to 4.0% and chilling injury severity from 59.3 to 20.0%. Respiration rates were similar between treatments. Only statistical differences on ethanol production were found: higher in the treated fruits, probably due to the storage temperature the very first 2 days, although no odd flavors were found. In conclusion, the application of LOT treatments prior to cold storage may be a promising strategy to preserve fruit quality of late season peach cultivars and deserves further investigation.

A great proportion of losses in apple production can be attributed to fruit physiological diroders, usually revealed during cold storage. These losses are commonly associated with metabolic processes in which calcium is involved. After years of study and experimentation in an attempt for reducing the incidence of Ca-related disorders by exogenous calcium treatments, a study published by Edna Pesis in 2007 opened another research route in this regard. This study, in Granny Smith, revealed that applying a treatment of low oxygen at room temperature, a considerable reduction of scald was achieved and pointed to a possible effect on alleviating bitter pit. It was hypothesized that low oxygen treatments may delay the metabolic activity of fruits and also delay ripening, softening and withering. Since 2008, we have continued to deepen into the development of alternative methods of low environmental impact which avoid the use of chemicals. Strategies have been developed for the application of LOT (Low Oxygen Treatment) treatments at room temperature in various apple varieties, obtaining promising results at the lab and at the semi-industrial scale. In this paper, LOT technology has been validated, this time, on an industrial scale. An Ilerfred system, with monitoring and control of CO2 and O2, was used. The LOT followed by conventional cold storage has proved too be very effective for the control of rots in all varieties, and was able to effectively control 'lenticel blotch pit' in Reinette. The results of the 2016 campaign compared to those of the two previous seasons allow us to conclude that improvement in shelf life of apples is achieved by combining different LOT conditions with the Dynamic Controlled Atmosphere (DCA) storage technology.

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