Submit Manuscript | http://medcraveonline.com Abbreviations: GP, germination percentage; MGT, mean germination time; CG, coeffcient of germination; SVI, seed vigor index; mM, milli molar; mT, milli tesla Introduction The history of agriculture begins with seed plantation, and the production of seed forms the foundation of the primary agriculture and the following civilization. Cropping of most of the plants depends on seed germination. Early growth of the crop leads to better competition with the weeds. There is a direct relation between germination in laboratory condition and growing in soil in favorable conditions of the farm among many plants. In dry parts of the world and Iran in which the plant faces natural stresses like, salinity stress and water stress at primary stages of germination and growth, using high vigor seeds is important. Therefore, it is emphasized to test the vigor of the seeds before sowing. 1 On the other hand, the mean germination time has a direct effect on the yield. This issue has been studied through investigating the methods of seed treatment like priming and salinity. Regarding the effect of salinity on the characteristics of seed germination, the results show that the salinity treatments have signifcant effect on some of the characteristics such as, the percentage of germination, the speed of germination, the radicle length, the plumule length and etc. 2–4 Different reports indicate that seed priming increases the percentage, speed and the uniformity of germination. 5–7 Pre–soaking of seeds has also been suggested as a manner for increase of germination. 8–10 Most of the studies have focused on crops and medicinal plants have received less attention. Medical plants are of economic plants of humans which store active and special biochemical substances. Using them to treat diseases is a small part of human civilization. Milk thistle (Silybum marianum L.) is one of the specifc medicinal plants that the effective substance of its seeds used in production of curing medicines for liver diseases. 11 The result of an experiment in relation to investigating the effects of salinity and drought stress on seed germination characteristics of Milk thistle showed that by increasing of salinity and drought stress, radicle and plumule length decreased. 12 The impact of magnetic feld on live systems behavior has been studied for long terms but, its impacts on plants have been studied only during recent decades. Meanwhile the mechanism of magnetic felds effect on plants is still remained unknown. 13 The results of an experiment about germination stimuli and the seedling growth of tomato (Lycopersicon esculentum L.) affected by magnetic feld indicated that 3mT magnetic feld permanently and 15mT for 25 minutes had the least time for germination. 14 The result of a research done about the impact of magnetic feld on seed germination of corn (Zea mays L.) has indicated that magnetic feld decreased the mean germination time of corn. It also has a positive effect on other germination characteristics of this plant. 15 The studies on the impact of magnetic felds on sunfower seeds (Helianthus annuus L.), have also indicated that sunfower seeds exposed to the magnetic felds had more germination speed, seedling length and seedling dry weight in comparison with control treatment. 16 Adv Plants Agric Res. 2015;2(6):255‒261. 255 ©2015 Solouki et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and build upon your work non-commercially. Investigating the seed germination characteristics of milk thistle (Silybum marianum L.) affected by magnetic feld, sodium chloride and hydro–priming Volume 2 Issue 6 - 2015 Hessamoddin Solouki, 1 Parviz Rezvani Moghaddam, 1 Ghasem Kord Phiroozjaee 1 1 Department of Agronomy, Ferdowsi University of Mashhad, Iran Correspondence: Parviz Rezvani Moghaddam, Professor of Agroecology, Department of Agronomy, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran, Tel: +98–15– 3179085; Email rezvani@um.ac.ir Received: September 15, 2015 | Published: October 13, 2015 Abstract In order to study the effect of the magnetic field, hydro–priming and salinity stress on the seed germination characteristics of Milk thistle (Silybum marianum L.) an experiment in factorial in the form of completely randomized design was executed. Treatments contain two levels of hydro–priming (soaking seeds in distilled water for 24hours and use the dry seed) seven levels of magnetic field treatment (50mT and 100mT for 20, 40 and 60 minutes and control treatment without magnetic field exposure). And 3 potential levels of salinity (0, 150 and 300mM NaCl) induced from Sodium chloride (NaCl). Results showed that the percentage of germination, the mean germination time, coefficient of germination, normal number of seedling, plumule length, radicle length, seedling length, vigor index, plumule fresh weight, radicle fresh weight and seedling fresh weight at the 5% level were significant. Hydro–priming improved the evaluated characteristics. Also according to the obtained results it was determined that increasing the concentration of NaCl, reduced the amount and growth of these characteristics. The results of the effects of the magnetic field also suggested that these effects were different under the strength and duration of the exposure. So that the treatments 50mT and 100mT for 20minutes, increased vigor index and seedling fresh weight by 6 and 10 percent respectively in comparison with control treatment. Keywords: magnetic field, medicinal plant, pre–soaking, salinity stress, seedling growth Advances in Plants & Agriculture Research Research Article Open Access