## 4 Discussion
There are conflicting data in the literature regarding the effect of salinity on strawberry fruit quality attributes. According to [PERSON] et al. [35] and [PERSON] et al. [39], salinity resulted in significant TSS reduction only under high levels of salt concentration, and increased TA in two strawberry cultivars, while in Camarosa fruit, the TA remained unchanged [35], as in the present trial. On the other hand, according to [PERSON] and [PERSON] [31] and [PERSON] et al. [60], the TA decreased significantly with salinity, indicating that cultivar and experimental conditions may have a significant influence, as has been also reported for the TSS content by [PERSON] et al. [55] and [PERSON] and [PERSON] [31]. The color of the fruit remained fairly stable, as reported also by [PERSON] et al. [39], indicating that salinity does not significantly change fruit pigment concentration. This was also evident as both Blank and Control treatment results exhibited similar anthocyanins concentrations. In general, salinity stress did not change fruit phytochemical content, regarding the concentration of the different groups of phenolic compounds, indicating that the biosynthetic pathways of phenolic compounds were more or less unaffected. This is in contrast to the results obtained by [PERSON] et al. [60], who reported significant decreases in total phenolic compound concentrations as well as a significant reduction in the antioxidant capacity of the fruit. Similar results have been reported for lettuce [62]. On the other hand, [PERSON] et al. [63] reported a significant increase in anthocyanins concentration and antioxidant capacity under mild salinity stress in strawberry. A slight increase of all groups of phenolic compounds and antioxidant capacity under saline conditions was also recorded here, but this was not statistically significant. In general, under stress conditions, the plant experiences oxidative stress due to the loss of control of the electron transfer chain, and it has to deploy its defense arsenal, which consists of both enzymatic and non-enzymatic molecules [64]. Non-enzymatic molecules able to confer tolerance against oxidative stress are the various phenolic compounds, which, to a point, protect plant membranes and functions from getting damaged and in the case of fruit, result in its biofortification with molecules beneficial for human health, as reported by [PERSON] et al. [64] for strawberry fruits. Beyond that point, though, and under continuous stress conditions and as stress elevates, the antioxidant mechanism is not able to protect membranes and functions, as the production of antioxidant molecules is surpassed by that of oxidative ones. Furthermore, the already present antioxidant molecules are used as defense agents, without being the plant able to substitute them. At this point, oxidative symptoms are developing in alignment with a reduction in plant defense molecules, as has been reported in strawberry fruits with increasing salinity stress [60]. Based on the heatmaps produced, it was found that antioxidant capacity (both measured by DPPH and FRAP assays) was positively related to Cl and Na concentration determined in the AGPM (primarily Cl) and roots (primarily Na). This indicates that stress imposition has triggered the antioxidant mechanism of the plant. All alleviation treatments though, enhanced the antioxidant capacity of the fruit compared with Blank treatment, thus fortifying the fruit with beneficial properties for human health [63]. It seems, thus, that some of the treatments act as elicitors of antioxidant defense against salinity, resulting in enhanced nutritional quality of the fruit. Among them, BETZ and GB proved to be more efficient in enhancing the anthocyanin content (especially BETZ) and the antioxidant capacity of the fruits, as has been observed in other plant species, too [41; 62; 65]. The sugar content of the fruit was not significantly affected by salinity, as it was slightly reduced.