Providing a Strategy to Confronting the Salinity Stress by Using the PGPR in a Desert Species (Calligonum comosum L`Her ) in Greenhouse Conditions

Abstract

The purpose of this study was to evaluating the philological effects of a plant growth regulator in the reduction of salinity stress in the Calligonum comosum L. In this regard, a factorial randomized complete block design (RCBD) in the greenhouse condition was implemented. The salinity levels included 0 in control, 2.5, 5, 10 ds/m (mild, moderate and severe stress) respectively. Also the PGPR used as a plant growth regulator with concentrations 0 as control, 10-10, 10-8 and 10-6 mmol. After applying the desired treatments for 3 months, total chlorophyll, the yield and antioxidant activity of essential oil in the Calligonum comosum L. Were measured with international standard methods. The essential oil, extracted by a Clevenger apparatus, and antioxidant activity examined by DPPH method. The results showed, the highest amount of total chlorophyll was observed was observed in the interaction of control treatment of salinity (0) and 10-8 mmol PGPR with values of 0.85mlg/g. The results of essential oil yield showed although the increase in salinity level reduced the essential oil yield, by using the PGPR could improve the essential oil yield to a satisfactory level. The highest amount of essential oil yield obtained in the mild salinity stress (2.5ds/m) and 10- 8 mmol PGPR concentration with values of 0.39g/cm. The results of antioxidant activity showed by using of PGPR the antioxidant activity improved in all of salinity stress level. Briefly, the results of this study showed that the use of PGPR is a suitable way to cope with the negative effects of salinity stress and increase the physiological performance of Calligonum comosum L.