en Effect of Salicylic Acid on Antioxidant Enzyms of Milk Thistle (Silybum marianum) Accelerated Aging Seed اثر سالیسیلیک اسید بر آنزیم های انتی اکسیدان تنظیم کننده های رشد گیاهی Plant Growth Regulators پژوهشي Research <p dir="ltr"><a name="OLE_LINK4"></a><a name="OLE_LINK3"><strong>Effects of accelerated aging and seed priming treatments were studied on milk thistle seeds during germination process. Experiment was performed in a factorial based on Complete Randomized Design (CRD). Treatments were Salicylic acid concentrations (0, 500, 1000, 1500 and 2000 ppm) and accelerated aging for (0, 48, 96 and 144 hours under 45 &deg;C and 95% humidity) with three replications. Our results showed thatsalicylic acid dramatically enhanced seed germination, seed vigor and primary seedling growth. Catalase, polyphenol oxidase and peroxidase activity was increased by seed priming. Reduction in germination parameters were observed by increase in accelerated aging durations</strong></a><strong> The highest antioxidant activity, germination percentage and daily germination rate and seed vigour were observed at primed seeds with 1000 ppm Salycilic acid on non-aged seeds. Treatment salicylic acid at a concentration of 1000 ppm has the greatest impact and cause harmful effects healing was aging.</strong><u><b>&nbsp;اثر سالیسیلیک اسید بر آنزیم های انتی اکسیدان</b></u></p> <p><a name="OLE_LINK4"></a><a name="OLE_LINK3"><strong>Effects of accelerated aging and seed priming treatments were studied on milk thistle seeds during germination process. Experiment was performed in a factorial based on Complete Randomized Design (CRD). Treatments were Salicylic acid concentrations (0, 500, 1000, 1500 and 2000 ppm) and accelerated aging for (0, 48, 96 and 144 hours under 45 &deg;C and 95% humidity) with three replications. Our results showed thatsalicylic acid dramatically enhanced seed germination, seed vigor and primary seedling growth. Catalase, polyphenol oxidase and peroxidase activity was increased by seed priming. Reduction in germination parameters were observed by increase in accelerated aging durations</strong></a><strong> The highest antioxidant activity, germination percentage and daily germination rate and seed vigour were observed at primed seeds with 1000 ppm Salycilic acid on non-aged seeds. Treatment salicylic acid at a concentration of 1000 ppm has the greatest impact and cause harmful effects healing was aging.</strong></p> Accelerated aging, Antioxidant enzymes, Catalase, Milk thistle, Peroxidase, Superoxide dismutase, Seed Priming کاتالاز Accelerated aging, Antioxidant enzymes, Catalase, Milk thistle, Peroxidase, Superoxide dismutase, Seed Priming 57 64 http://jispp.iut.ac.ir/browse.php?a_code=A-10-308-14&slc_lang=en&sid=1 Ghasem Parmoon قاسم پرمون ghasem.parmoon@gmail.com Yes Faculty of Agriculture, University of Mohaghegh Ardabil گروه زراعت ، دانشکده کشاورزی دانشگاه محقق اردبیل Ali Ebadi علی عبادی ebadi@uma.ac.ir No Faculty of Agriculture, University of Mohaghegh Ardabil گروه زراعت ، دانشکده کشاورزی دانشگاه محقق اردبیل Soodabe Jahanbakhsh Gode kahriz سدابه جهانبخش Jahanbakhsh@uma.ac.ir No Faculty of Agriculture, University of Mohaghegh Ardabil گروه زراعت ، دانشکده کشاورزی دانشگاه محقق اردبیل Seyed Amir Mossavi سید امیر موسوی No 3. University of Tarbiat Modares, Department of Agronomy, Faculty of Agriculture, Tehran, Iran. گروه زراعت ، دانشکده کشاورزی دانشگاه تربیت مدرس