EFFECT OF EXOGENOUS APPLICATION OF CITRIC ACID ON GROWTH OF MAIZE (ZEA MAYS L.) UNDER SODIUM FLUORIDE STRESS

Fluoride toxicity is a leading cause of environmental pollution and is particularly considered as a phytotoxic element for cereal crops. Accumulation of high amount of fluoride in the soil alters the metabolism of plants and reduces their growth. Therefore, an experiment was conducted to understand the effects of sodium fluoride (NaF) on the plant growth and the amelioration of its toxic effects by the application of citric acid on the two cultivars of maize, Pak Afgoi (salt tolerant) and Pearl (salt sensitive). NaF in a concentration of 100ppm and 200ppm was applied to one week old seedlings. Citric acid (100 mgL-1 and 150 mgL-1) was applied as a foliar spray after two weeks of application of NaF salinity stress. The data regarding shoot length, shoot, root fresh and dry weight, chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, ions and ash contents were collected after fifteen days of citric acid application. Our results showed that citric acid 150 mgL-1had a positive effect on the growth of maize plants and had reduced the toxic effects of sodium fluoride.