Germination and growth parameters of seedlings of Oenothera biennis L. as affected by salinity stress

A major problem of arid and semi-arid regions is environmental stresses like salinity. To study the effect of salinity on germination characteristics of Evening primrose (Oenothera biennis L.), a completely randomized experiment was conducted under controlled conditions (germinator) with three replications in Department of Agronomy, Birjand Branch of Islamic Azad University, Birjand, Iran in 2011. The experimental treatments included salinity levels (0, 2, 4, 6 and 8 ds m-1). The studied traits included seedling length and dry weight, germination percentage and rate, and seed viability index. It was found that salinity significantly decreased seedling length and weight, germination rate and percentage and seed viability index of Oenothera biennis L., so that means comparison for these traits showed that the application of 8 ds m-1 salinity resulted in the loss of seedling length, seedling weight, germination percentage, germination rate and seed viability index of Evening primrose seeds by 41.7, 40, 28.2, 33.1 and 58.4% respectively, as compared to control. In total, it can be concluded that salinity stress significantly decreased germination and growth parameters of seedlings of Evening primrose.