Effect of different levels of salinity and temperature on seed germination of Cocks Comb (Celosia argentea)

Due to the existence of salinity and high temperature in Khuzestan region, a factorial experiment was carried out to investigate the effect of 5 levels of salinity (0, 3, 6, 12 dS/m) and 2 levels of temperature (25ºC, 35ºC) on seed germination of Celosia argentea in a Completely Randomized Design with 3 replications. ANOVA results revealed that the effect of salinity and temperature on germination percentage, germination rate and radical length were significant (P<0.01), but the interaction between salinity and temperature on germination percentage were significant (P<0.05). Mean comparison of germination percentage indicated that germination percentage decreased with increasing of salinity. Seed germination percentage decreased 20.44% from 12 dS/m to control treatment. Also, the highest and lowest radical length as 70.6 and 19.2 belonged to control and 12 dS/m, respectively. Effect of temperature on germination percentage, germination rate and radical length indicated that the highest germination percentage, germination rate and radical length were obtained in 25ºC. With increasing temperature from 25ºC to 35ºC, seed germination percentage in 6, 9 and 12 dS/m decreased about 14%, 17.63% and 18.33%, respectively, in comparison with control treatment. Also, in all of salinities, seed germination per day decreased as 3 seeds per day.