G Rabani, R Ezati,
Volume 15, Issue 1 (4-2015)
Abstract
Acid rain, which is a wet form of gaseous air pollutants, is formed when air pollutants such as SO2, NO2, CO2 in atmosphere combine with water vapor of clouds. With the addition of concentration of these pollutants the amount of acid rain is increases. Acid rain that is the mixture of sulphuric acid, nitric acid and carbonic acid lead to change in the soil like the decrease in pH, nutrient liberation, the increase of releasing in toxic metals and the decline in fertility of soil that these cases results negative effects on plants. In present work wheat plants irrigated and leaf spraied with four treatments of acid rain which contain sulphuric acid and nitric acid with pH= 2.5, 3.5, 4.5, 5.6 for a period of 32 days, whereas, control plants irrigated and leaf spraied by normal water at pH= 7.4 . According to the results control plants in whole of growth and physiological indexes were better than treatments of acid rain at pH= 2.5 and 3.5, also plants of acid rain treatment at pH= 4.5 and 5.6, were lower in other factors except photosynthetic rate, pigment content and carbohydrate content than control plants. Also acid rain at pH= 2.5 and 3.5 causes white spot in both surface of leaf and tip and border atrophy.
