Effect of Salicylic acid on salinity and alkalinity resistance in sweet pepper plant

Salinization and alkalization of soils are an agricultural problems in arid and semiarid regions of the world such as Iran. In this experiment the effects of salicylic acid (SA) on resistance of pepper under salt and alkali stresses was investigated. Experimental treatments include 0 and 150 mM of NaCl stress, 0, 50 and 100 mM of Na2Co3/NaHCo3 and 0. 0.75 and 1.5 mM SA. Results showed that salt and alkali stresses imposed negative effects on plant growth and productivity. Reduction in growth and yield in salinity condition was higher than alkaline condition and maximum reduction occurred in mixed stresses. Application of SA in both conditions significantly increased yield, plant growth parameters and chlorophyll content. For most traits, 0.75 mM of SA was more effective than 1.5mM concentration. In general, Salinity and alkalinity have negative effects on growth and yield of pepper plant and these negative effects can be reduced by application of SA.