The effects of pre-chill and temperature on seed dormancy, growth and establishment indices of Smyrniopsis aucheri Boiss

Smyrniopsis aucheri BOISS is an herbaceous species of Apiaceae family which seed germination is difficult. Therefore, to restore the natural habitats of this plant, it is necessary to provide information about the length and the factors that affecting seed dormancy of this plant. In order to study effect of the duration of chilling and temperature on seed dormancy and seedling establishment of Smyrniopsis aucheri, this experiment was conducted as factorial in a randomized design. Factors were included the pre-chilling duration in 7 levels (0, 10, 20, 30, 40, 50 and 60 days), level of chilling (with and without chilling) and temperature in 4 levels (5, 10, 15 and 20 ° C).The results showed that the combination of chilling and temperature treatment had the highest effect on stimulation of seed germination under certain conditions, and chilling treatment less than 30 days had no significant effect on seed germination. The results showed that chilling at 5 ° C for 60 days, was the most effective treatment on breaking dormancy in S.aucheri. Germination percentage (51.9%), germination rate and seed vigor increased significantly in this treatment, compared to control treatment. In relation to growth indices, the results showed that chilling 20 ° C for 60 days was the most effective treatment on seedling growth indices. Overall, according to the results, In order to improve the seedling establishment of Smyrniopsis aucheri, the use of chilling for 60 days, which markedly enhanced all of the seedling establishment indices, is recommended.