Effect of salinity on growth and leaf area of sunflower (Helianthus annuus L.) cv. suntech - 85

A pot experiment was conducted during 2009 to 2010 to access adverse effect of salinity on growth of sunflower (Helianthus annuus L.) cv. Suntech 85. The result revealed that with increasing salinity concentration, the growth parameters declined except at lower salinity level 5 E.C. which does not show any adverse effect rather, there was slight increase in all growth parameters as compared to control. Whereas, higher salinity level with 25 E.C. was deleterious and showed a decrease of 20.96, 39.92 and 22.44% in shoot length, 35.93, 33.33 and 31.50% in root length, 56.46, 29.95 and 28.81% in shoot fresh weight, 42.42, 51.28 and 34.73% in root fresh weight, 30.26, 45.54 and 27.08% in shoot dry weight, 63.41, 55.00 and 57.29% in root dry weight and 44.82, 42.30 and 38.14% in leaf number and 41.56, 33.04 and 40.00% in leaf area as compared to control at 30, 60 and 90 DAS respectively. This decrease in growth at higher salinity levels might be due to the toxic effects of salinity, which badly affected plant physiological aspects such as osmotic adjustment and ion accumulation creating drought-like conditions for the plant.