evaluation of germination behavior of kochia seed (kochia scoparia l. schard.), under different temperatures and salinity stress levels

kochia (kochia scoparia l. schard) is an annual, halophyte and drought resistant plant that can be irrigated with saline water and a valuable source for forage under drought and saline ecosystem. in order to evaluate the germination characteristic of kochia under different temperatures and salinity stress levels, an experiment was conducted at physiology lab of ferdowsi university of mashhad, iran during year of 2009. the experiment was conducted in a completely randomized design with four replications. treatments included nine levels of salinity (0, 5, 10, 15, 20, 25, 30, 35 and 40 ds.m-1) using nacl and eight temperature levels (5, 10, 15, 20, 25, 30, 35 and 400c). analysis of variance showed that the different levels of temperature and salinity stress had significant effects (p≤0.05) on percentage of germination, mean germination time, germination index, dry weight and length of seedling and interaction between temperature and salinity stress had the same effect. the highest percentage of germination was in 250c and in control levels that didn’t show any significant effect with 5 and 10 ds.m-1. the shortest mean germination time observed at 250c (20.1, 21.1 and 11.1 days in three primary treatments) and the highest one observed in 35 ds.m-1 at 100c. the highest germination index (20.37) occurred at 250c and in control level. also, by increasing in salinity level, dry weight and length of seedling decreased. anyway, based on the results of the present study, kochia is able to germinate in different salinity levels and has a high ability to recover itself.