The effect of salicylic acid foliar spraying on morphophysiological characteristics of common mallow and Moldavian balm

Salicylic acid has an important role in some plant physiological processes as a plant growth regulator. In current study, the effect of salicylic acid on morphological and physiological traits of common mallow and Moldavian balm was studied based on completely randomized block design in farm condition at Bostanabad county, Iran. Plantlets were sprayed by 0, 150 and 300 mg/L salicylic acid two month after planting and two weeks after. In flowering stage, the plant height, stem, root and internode length, leaf, root and lateral roots number, dry and fresh weight of stem, root and leaf, dry matter percentage of root, stem and leaf and also chlorophyll content were recorded. Salicylic acid spraying improved all common mallow traits but root number and length. In Moldavian balm, salicylic acid application increased all traits. However, it decreased root and stem dry matter percentage and had no effect on root number and length. Also, 300 mg/L of salicylic acid was more effective than 150 mg/L in common mallow traits except dry leaf weight and root dry matter percentage and in Moldavian balm expect length internode. Thus, foliar spraying of salicylic acid can be recommended for as a simple and economical method for yield and growth indices improvement of common mallow and Moldavian balm.