Effect of salicylic acid on basil resistance against lead

The aim of this study was to evaluate the effects of salicylic acid on lead toxicity in basil following lead addition to soil. This experiment was conducted as Randomized Complete Block with Factorial arrangement. Factors included the 4 levels of lead nitrate; 0 (control), 100, 200 and 300 mg per kg of soil and foliar application of salicylic acid at 3 levels of 0, 50 and 100 ppm. Phytotoxicity of Lead was determined as plant growth, concentration of photosynthetic pigments and catalase enzymes. Addition of lead significantly reduced dry weight of shoots and roots and photosynthetic pigments and increased soluble carbohydrates, catalase and peroxidase. In addition, salicilic acid spraying had a significant influence on all traits. In this study the interaction between salicylic acid and lead on shoot fresh and dry weight, root fresh weight, chlorophyll a and b, carotenoids, carbohydrates, catalase and peroxidase were significant, and salicilic acid play moderating role and reducing the negative effects of lead toxicity. The results of this experiment suggested salicylic acid application in basil can be reduced lead toxicity by increasing growth and concentration of photosynthetic pigments.