3.6 Fatty acid profile
The effect of water stress and PGPB treatment on the obtained fatty acid profiles in gas chromatography is depicted in Table 5. Water stress increased the main saturated fatty acids (SFA) content including palmitic acid (C16:0) and stearic acid (C18:0) in no-inoculated and inoculated plants, but the content of palmitic acid and stearic acid decreased in all of the inoculated plants in comparison with the no-inoculated plant. As illustrated in the Table 4 the highest palmitic acid and stearic acid (9.99 and 3.69% respectively) in no-inoculated plants were related to B0D2 and in inoculated plants, it was related to B1D1which accounted 9.18 and 3.49% respectively for palmitic acid and stearic acid content. The effect of water stress and PGPB on monosaturated fatty acids (MUFA) were significant. Oleic acid (18:1), eicoseonic acid (20:1) and erucic acid (22:1) content significantly declined by 46, 22.5 and 45.9 % under water stress respectively. In inoculated plants, the highest oleic acid and eicoseonic acid content were seen in mild water stress (B1D1). In comparison with control, the highest and the least erucic acid content is related to B1D0 and BD2 respectively. As the increase of erucic acid content coincided with the increase of drought stress levels. The highest proportion of fatty acids was related to polyunsaturated acid (PUFA) including linolenic acid (C18:3) and linoleic acid (C18:2) content. The water-deficit stress in particular (75% FC) increased linoleic acid content in both of the inoculated and no-inoculated plants. The PGPB treatment significantly decreased linoleic acid content. The linolenic acid content ranged from 33.40 to 43.44%. Both of the PGPB and water deficit treatment increased the linolenic acid content. According to Table 5 linolenic acid (18:3) content negatively correlated with linoleic acid (18:2) in the inoculated plants. As the highest linolenic acid (43.44%) coincided with the least linoleic acid (18.53%) content. In general, water-deficit stress increased the total SFA content (6.04%) and total PUFA (<0.1%) content. Adversely, a total MUFA reduced in stressed plants, as the highest MUFA content (30.38%) related to B1D0. The Fig 5 A-C showed the correlation between oil content with the total content of SFA, MUFA, and PUFA in the all of treatments, as there was a severely positive correlation between oil and MUFA and adversely for SFA and PUFA content.