Effect of salicylic acid on improving chilling stress damage in corn hybrid SC 400 (Zea mays L.)

Chilling stress usually can be seen in tropical and subtropical crops or in crops which are grown in afore mentioned areas. Generally, the crops are very sensitive to chilling stress during their active growth and early stages of their development. In this research, a study on the effects of chilling stress and salicylic acid on physiological and biochemical traits of corn hybrid single-cross 400 in factorial arrangement in a completely randomized design in the research greenhouse of Ferdowsi University of Mashhad has been investigated. To this, chilling stress in two levels (i.e. non-stress control, and chilling stress at 5⁰C in four-leaf satge using thermogradient freezer for 12 hours) as the main factor and three levels of spraying salicylic acid solution (non-spraying control, 200 and 400 micro molar spraying) as subsidiary factor was applied. The results showed that the concentrations of malondialdehyde, Di-tyrosine and proline increased and the activity of superoxide dismutase, glutathione peroxidase and catalase enzymes decreased significantly in chilling stress. Spraying of 200 and 400 micro molar salicylic acid solution ameriolated the negative effect of chilling stress. Electrolyte leakage increased, while, water content and dry matter accumulation and leaf area has been decreased in the presence of chilling stress. Spraying of salicylic acid solution caused an increase in chlorophyll content. Indeed, a significant correlation between the cold damage, salicylic acid treatment, and investigated traits were appeared that represent the corn seedling’s positive reaction to salicylic acid in chilling stress condition. 400 mM salicylic acid proline sprayed most of the 39.5 micromoles per gram of fresh weight, respectively.