## 3 Results and Discussion
### Leaf Nutrient Composition
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Treatment**} & **Chlorophyll a** & **Chlorophyll b** & **Total Chlorophyll** & **Carotenoids** \\  & **mg g\({}^{-1}\) fw** & **mg g\({}^{-1}\) fw** & **mg g\({}^{-1}\) fw** & **mg g\({}^{-1}\) fw** \\ \hline EC0 & 1.03 \(\pm\) 0.01 & 0.57 \(\pm\) 0.02 a & 1.61 \(\pm\) 0.03 a & 0.323 \(\pm\) 0.012 b \\ EC2 & 1.01 \(\pm\) 0.01 & 0.52 \(\pm\) 0.01 ab & 1.52 \(\pm\) 0.02 b & 0.348 \(\pm\) 0.006 a \\ EC4 & 1.02 \(\pm\) 0.01 & 0.53 \(\pm\) 0.01 ab & 1.58 \(\pm\) 0.04 ab & 0.329 \(\pm\) 0.009 ab \\ EC6 & 1.00 \(\pm\) 0.01 & 0.49 \(\pm\) 0.02 b & 1.50 \(\pm\) 0.03 b & 0.328 \(\pm\) 0.005 ab \\ BC & 1.00 \(\pm\) 0.01 b & 0.50 \(\pm\) 0.01 b & 1.52 \(\pm\) 0.03 b & 0.326 \(\pm\) 0.010 \\ BA & 1.01 \(\pm\) 0.01 b & 0.51 \(\pm\) 0.01 b & 1.52 \(\pm\) 0.02 b & 0.340 \(\pm\) 0.006 \\ BT & 1.05 \(\pm\) 0.01 a & 0.57 \(\pm\) 0.02 a & 1.62 \(\pm\) 0.02 a & 0.329 \(\pm\) 0.005 \\ I & 1.04 \(\pm\) 0.02 a & 0.57 \(\pm\) 0.02 a & 1.60 \(\pm\) 0.03 ab & 0.348 \(\pm\) 0.005 b \\ II & 1.00 \(\pm\) 0.01 ab & 0.57 \(\pm\) 0.02 a & 1.54 \(\pm\) 0.03 a-c & 0.397 \(\pm\) 0.005 a \\ III & 1.04 \(\pm\) 0.01 a & 0.55 \(\pm\) 0.02 ab & 1.59 \(\pm\) 0.03 ab & 0.342 \(\pm\) 0.003 b \\ IV & 0.98 \(\pm\) 0.01 b & 0.52 \(\pm\) 0.02 a-c & 1.47 \(\pm\) 0.03 c & 0.334 \(\pm\) 0.004 b \\ V & 1.03 \(\pm\) 0.01 ab & 0.50 \(\pm\) 0.01 bc & 1.63 \(\pm\) 0.05 a & 0.296 \(\pm\) 0.010 c \\ VI & 1.02 \(\pm\) 0.01 ab & 0.47 \(\pm\) 0.01 c & 1.49 \(\pm\) 0.02 bc & 0.276 \(\pm\) 0.010 c \\ \hline \hline \end{tabular} Different letters within each column and for the same factor indicate significant differences according to Tukey\({}^{5}\) honestly significant difference (HSD) test at \(\pm\) 0.05. EC0: tap water (0 d s\({}^{-1}\)), EC2: 2.0 d s\({}^{-1}\): EC4-d 0.d s\({}^{-1}\); EC6: 6.0 d s\({}^{-1}\); BC: no biostimulants added; BA: plants treated with Auzym@s and BT: plants treated with Trainer@. The Roman numbers (I–VI) indicate the successive harvests. All data are expressed as mean \(\pm\) SE (standard error), \(n=3\).  
\end{table} 
Table 4: Effect of salinity, biostimulant, and harvest on chlorophyll a, chlorophyll b, total chlorophylls, and carotenoid averages in _Diplotaxis tunifolia_. leaves, whereas biostimulant application showed no significant effect. Similarly, K, P, Ca, and Mg content decreased with increasing salinity, while biostimulant application only affected P content [17]. Moreover, increased salinity has been associated with the disruption of nutrient and osmotic balance due to increased ratios of Na/K, Na/Ca, and Na/Mg [63]. Nitrate content was significantly increased by biostimulant application for all of the tested salinity levels compared to the untreated plants (no biostimulants added), while a decreasing trend with increasing salinity was recorded for all of the biostimulant treatments (with or no biostimulants added) (Table 5). Similar results were recorded by [PERSON] et al. [16], who also suggested an increase in nitrate content in spinach plants treated with a legume-derived protein hydrolysate, while increasing salinity also resulted in a significant decrease in nitrate. It seems that the high availability of Cl in the nutrient solution may impair nitrate uptake and decrease its content in plant tissue, while biostimulants may serve as nitrogen pools and contribute to the accumulation of nitrate in leaves without an increased uptake of exogenous nitrogen being observed [64; 65]. In contrast, [PERSON] et al. [62] reported a decrease in nitrate content in wild rocket plants treated with forage extracts, which indicates that biostimulant composition and the presence of nitrogenous compounds could be responsible for the increase in nitrate observed in other studies. Moreover, [PERSON] et al. [57] recorded a variable effect of increasing salinity on nitrate content in wild rocket plants, depending on the cropping system and the genotype tested. Similarly, [PERSON] et al.