The Effects of Gamma Radiation on Seed Germination and Vigour of Caper (Capparis spinosa var. parviflora) Medicinal Plant

In this study, the effect of different doses of gamma radiation was investigated on seed germination factors of Caper species. Gamma irradiation was performed using a cobalt-60 radiation with the radiation speed of 0.018 Gray/second and five doses of gamma radiation (0, 20, 40, 60 and 100 Gray) in a completely randomized design with 4 replication. The results showed that gamma radiation significantly affects some of the seed germination factors. So that the 100 Gray treatment increased the germination percentage up to 43.2% as compared with other treatments. The average time of germination in seeds treated with gamma decreased 0.91 days rather than control. Length of the stem let in gamma treatments increased 62.3% rather than control; so that the fresh and dry weight of stem let at 100 Gray were respectively increased 171.4 and 27.3% in comparison with the control. Fresh and dry weight of root lets were respectively increased 417.9% and 668% rather than the control one. Seed vigor at 100 Gray was 32.3% higher than the control. From among the different studied doses, 100 Gray showed highest influence on the seed germination and physiology although the induced changes were in low amounts. This study revealed that gamma irradiation has not major influences on improving seed germination characteristics of Caper shrubs.