## 2 Materials and Methods
### Experimental Design and Growth Conditions  
The vitroplants were acclimatized for two months in a greenhouse with a day/night temperature of 26 \({}^{\circ}\)C, fluorescent lighting of 500 \(\mu\)molm\({}^{-2}\)s\({}^{-1}\), a 16/8 h light/dark photoperiod and relative humidity of 68.5%. After this period, each vitroplant was transferred to a 4 L plastic pot containing 3.5 kg of sterilized soil. The soil was collected in the urban area of the Commune of Marrakesh (31\({}^{\circ}\)39\({}^{\circ}\)07.3\" N, 8\({}^{\circ}\)04'04.3\" W). The soil was passed through a4 mm sieve and autoclaved (at 180 \({}^{\circ}\)C for 3 h and repeated 3 times consecutively). The characteristics of the agricultural soil used in this study are mentioned in Table 1.  
The experiment was set up in a randomized complete block design with two factors: biofertilizer application and salt stress levels (0, 120 and 240 mM of NaCl). During transplantation, the biofertilizer treatments were established, consisting of different levels: Two AMF treatments--a  
\begin{table}
\begin{tabular}{c c c} \hline \hline  & **Soil** & **Compost** \\ \hline pH & 8.60 (0.08) & 7.74 (0.01) \\ EC (\(\mu\)S cm\({}^{-2}\)) & 190.00 (0.45) & 5460.00 (0.20) \\ NTK (\%) & 0.11 (0.01) & 1.32 (0.01) \\ NH\({}_{4}\)\({}^{+}\) (\%) & - & 0.09 (0.01) \\ NO\({}_{3}\)\({}^{-}\)(\%) & - & 0.31 (0.01) \\ TOC (\%) & 0.59 (0.12) & 5.72 (0.45) \\ OM (\%) & 1.02 (0.20) & 9.86 (0.78) \\ C/N & - & 7.49 \\ NH\({}_{4}\)\({}^{+}\)/NO\({}_{3}\)\({}^{-}\) & - & 0.29 \\ P\({}_{\mathrm{olsen}}\) (ppm) & 11.00 (0.22) & 489.95 (0.29) \\ Na\({}^{+}\) (ppm) & 990.00 (30.00) & 2110.00 (50.00) \\ K\({}^{+}\) (ppm) & 890.00 (50.00) & 5590.00 (150.00) \\ Ca\({}^{2+}\) (ppm) & 11,480.00 (480.00) & 37,380.00 (1840.00) \\ \hline \hline \end{tabular} EC: electrical conductivity; NTK: total Kieldahl nitrogen; TOC: total organic carbon; OM: organic matter; C/N: ratio of carbon to nitrogen. Data presented are means (with standard deviation).  
\end{table}
Table 1: Physicochemical parameters of the soil and compost.  
PGPR treatment and a compost treatment established alone or in different combination, as described below. For the compost treatments, 2.375 kg of soil was mixed with 0.125 kg of compost at a rate of 5% and homogenized. The AMF treatments received either the native mycorrhizal consortium or the pure inoculum of _R irregularities_. Inoculation was performed by adding 10 g of fresh inoculum containing root fragments and spores as closely as possible to the roots when transplanting. The non-mycorrhizal control received the same weight of previously autoclaved mycorrhizal inoculum. The PGPR treatments were inoculated twice, first during transplantation and 15 days later by spraying 15 mL (\(5\times 109\) colony forming units (CFU)/mL) of the bacterial suspension as closely as possible to the roots using a micropipette.  
The pots were grown for 4 months under controlled conditions (as described above) in the glasshouse at the Faculty of Science Semlalia, Cadi Ayyad University, Marrakesh, Morocco. Then, the vitroplants were subdivided into three groups: a control group without salt stress (0 mM NaCl), a second group supplemented with 120 mM of NaCl and a third group with 240 mM of NaCl. Each group consisted of twelve biofertilizer treatments:  
Control plants without any biofertilizer (Control);  
Plants amended with compost (Comp);  
Plants inoculated with the native AMF consortium (AMF\({}_{1}\));  
Plants inoculated with the exotic AMF strain (AMF\({}_{2}\));  
Plants inoculated with the PGPR consortia (PGPR);  
AmF\({}_{1}\)+Comp,  
AmF\({}_{2}\)+Comp,  
PGPR+Comp,  
PGPR+AMF\({}_{1}\),  
PGPR+AMF\({}_{2}\),  
PGPR+AMF\({}_{1}\)+Comp,  
PGPR+AMF\({}_{2}\)+Comp.  
In total 36 treatments were established with 8 replications for each treatment (one plant per pot is considered as a replicate), yielding a total of 288 pots.