## 4 Discussion
This slight reduction could be ascribed to the reduced leaf area, resulting in lower photosynthetic activity and thus lower supply of photoassimilates to the fruits, as has been proposed by [39], who also detected reductions of fruit carbohydrate content. Furthermore, as oxidative stress might have begun (judging from the toxicity signs on the leaves), photosynthesis might have been impaired to a great extent, contributing also to the reduced carbohydrate concentration found in the fruits. Individual (apart from malic acid), as well as the total organic acids, were significantly increased under saline conditions. Similar results have been reported by many authors working with strawberry [4; 31], while a non-significant change in the levels of ascorbic acid has been also recorded [66]. BETZ and BA primarily, and GB secondly resulted in non-significant differences with the Blank treatment regarding total organic acid concentration. As salinity induced an elevation of organic acid accumulation in the fruits, it can be assumed that the former two treatments alleviated to some extent the negative effects on salt stress, regarding the organic acid content of the fruits. The mineral content of the plant was significantly affected by salinity, apart from the majority of micronutrients, as has been previously reported [56]. In general, N, K, Mg, and Ca were significantly reduced, while Na, Cl, and the Na/K and Na/Ca ratios were significantly increased, in both leaves, roots, and whole plant. According to several authors, Cl is the element responsible for the toxic symptoms in strawberry, as it is absorbed by cell membranes and it is translocated to the upper part more easily than Na [55; 57; 67]. In the present experiment, the Na content in the leaves increased by almost 240% in Control compared with Blank, as similarly reported by others [55; 56; 68], while that of Cl increased by almost 196%. On the other hand, Na content in the roots increased by 550% while that of Cl increased by 183%, indicating that a substantial amount of Na was retained at the root level, as reported by other authors too [55; 67]. Furthermore, Cl concentration in the leaves has been related to leaf tissue necrosis [67], as in the present experiment, where Cl both in roots and leaves was positively related to toxicity symptoms and negatively to tolerance index. Nitrogen content in the leaves of all plants subjected to salinity was significantly reduced and this may be ascribed to the inhibition of NO\({}_{3}\)\({}^{-}\) translocation from the root to the upper plant part due to competition with Cl [56; 67]. According to [PERSON] and [PERSON] [67] the anion channels in the xylem parenchyma cells may exhibit similar permeability for both NO\({}_{3}\)\({}^{-}\) and Cl\({}^{-}\) and under conditions favoring Cl\({}^{-}\) concentration (i.e., salinity stress); NO\({}_{3}\)\({}^{-}\) loading and translocation would be impaired. Potassium on the other hand is known to compete with Na uptake and translocation and this is usually in favor of Na, as this is the major mineral found in the root zone under saline conditions [47; 69]. This leads to reduced K concentration in the leaves as determined also here [69]. Calcium and Mg content were also reduced in leaves and the whole plant, similar to those reported by [PERSON] et al. [39] and [PERSON] et al. [60], while Ca content in roots slightly increased in Control, as reported also by [PERSON] and [PERSON] [56], indicating that Ca accumulation in the roots acts as a protection mechanism against severe toxicity. Phosphorus was significantly decreased under saline conditions in leaves while it remained unaffected in roots. Decreased P concentration in the tissues has been reported by others too [47; 60], while [PERSON] [67] and [PERSON] and [PERSON] [56] have reported increases of P in strawberry under saline conditions or non-significant changes [67]. In general, the influence of salinity on P is quite variable in plants and depends on many factors, among which cultivar plays a significant role [47].