Interactive effects of salt stress and salicylic acid on germination and plant growth parameters of maize (Zea mays L.) under field conditions

Two experiments were conducted to study the impact of salt stress and salicylic acid (SA) on seed germination and plant growth of maize (SC704) under field conditions in the city of Kerman in 2010. For germination experiment, SA seed pretreatments included; control, water soaked, SA soaked in 0.1 and 0.2 mM for 24 hours and salt treatment included; control, 40 and 80 mM NaCl. All seed germination parameters including germination percentage, mean germination time, germination uniformity, radicle and root length and seedling dry weight were adversely affected by salt stress. SA especially at 0.1 mM improved all parameters significantly, especially under salt treatment. Under field conditions (40 mM salinity), 0.1 mM SA improved chlorophyll, relative water content, membrane permeability, fresh and dry weight of forage, comb length, grain yield, 1000 seed weight, water use efficiency and K+ in leaf. However, leaf Na+ content was significantly lower when SA was used. Thus, it was concluded that seed pretreatment with SA could be used commercially to improve plant performance and yield in maize under salt stress conditions.