EFFECT OF FLUORIDE TOXICITY ON PHYSIOLOGICAL AND BIOCHEMICAL PARAMETERS OF WHEAT (TRITICUM AESTIVUM)Rekha Sodani, J.P. Srivastava and Vijai, P.Abstract Wheat is the second most important cereal crop next to rice. Fluoride toxicity effects on physiological (relative water content, chlorophyll and carotenoids) and biochemical (soluble sugar, starch, free amino acid, proline and malondialdehyde (MDA) contents parameters of wheat plants from their germination to maturity and ultimately reduces the yield.A pot experiment was conducted to investigate the effect of different concentrations [0 (T1), 50 (T2), 100 (T3), 200 (T4), 250 (T5) and 300 (T6) mg fluoride kg-1 soil] of fluoride in wheat variety HUW-234. Observation was recorded at 30, 60 and 90 DAS. The results indicate that increased level of fluoride decline RWC, chlorophyll, carotenoids, starch, soluble protein, free amino acid while chlorophyll a: b ratio, soluble sugar, proline and MDA contents increased. The present study revealed that fluoride increased concentrations of soluble sugars, proline and MDA indicated that like other stresses fluoride also caused oxidative stress in wheat. Chlorophyll a : chlorophyll b ratio also increased in plant leaves exposed to fluoride. It is noted that fluoride caused more reduction in level of accessory photosynthetic pigments (chlorophyll b and carotenoids) than in the level of main photosynthetic pigments. |