Effect of different levels of salinity on germination and early seedling growth of sunflower

Abstract

An incubation experiment was conducted at the Department of Soil Science, Patuakhali Science and Technology University during Rabi season 2015 to investigate the salinity effect on germination and early seedling growth of sunflower. There were ten treatments consisting different concentrations of salinity viz. 0, 20, 40, 80, 120, 160, 200, 240, 280 and 320 mM NaCl. The germination experiment was conducted in petri dish lined with a layer of cotton consisting ten ml of each test solution. Germination percentage gradually decreased with the increase of concentration of salt. Up to 80 mM NaCl was identified as safe for sunflower seed germination. Salinity cause delay in germination. Highest seedling height was found at 40 mM NaCl concentration (13.09 cm) and root length (14.1 cm) in 20 mM NaCl concentration. In 320 mM NaCl concentration roots were abnormal, deformed and twisted. The 0 to 80 mM NaCl concentration gave statistically similar shoot fresh weight. Compared to control treatment 20 and 40 mM NaCl concentration gave 0.57 and 4.65 % higher fresh weight, respectively which indicates that lower concentration of salt favor plant growth. The 80 mM NaCl concentration could be identified as safe for germination and early seedling growth of sunflower.