重离子束辐照对甜高粱幼苗存活率及抗氧化酶活性的影响

目的]研究重离子束辐照甜高粱种子后对其发芽势、存活率和抗氧化酶活性、脂质过氧化作用等的影响,探讨重离子束辐照甜高粱的生物学效应。方法]利用兰州重离子加速器产生的能量为100 MeV/u的12C6+离子束对2个甜高粱品系干种子进行剂量为0、40、80、120、160和200 Gy辐照,研究种子发芽势、存活率和抗氧化酶活性。结果]重离子束辐照处理对甜高粱发芽势和存活率的影响变化不一致,发芽率呈现肩型下降趋势,但其对应的幼苗存活曲线总体上呈"类马鞍型"。SOD、POD、CAT及ASA-POD等的酶活性变化趋势也不相同,MDA含量随辐照剂量增加呈上升趋势,说明高剂量的重离子束辐照对甜高粱幼苗的膜损伤加重。结论]重离子束辐照处理降低了甜高粱的发芽势和存活率,对甜高粱幼苗抗氧化酶活性有不同程度的影响,该研究结果为下一步进行重离子束辐照选育和改良甜高粱品种奠定了基础。

Effects of Heavy-ion Beam Irradiation on Survival Rate and Antioxidant Enzymes of Sweet Sorghum Seedlings

Objective] This study aimed to investigate the effects of heavy-ion beam irradiation on the seed germination potential,survival rates,antioxidant enzyme activities and lipid peroxidation of sweet sorghum.Method]The dry seeds were irradiated by 12C6+ heavy ion beam with absorbed dose:0,40,80,120,160 and 200 Gy,respectively.Then,the seed germination potential,survival rates,antioxidant enzyme activities and lipid peroxidation of sweet sorghum were measured.Result] Heavy-ion beam irradiation exhibited different influence on germination potential and survival rates.Germination rate showed a downward trend,but the corresponding survival curve of seedlings was saddle-shaped.The activities of SOD,POD,CAT and ASA-POD changed in different trends as well.The MDA content was increased with the increasing dose of irradiation,suggesting that high dose of heavy-ion beam irradiation enhanced the damage to membrane of sweet sorghum seedlings.Conclusion] After being irradiated,germination potential and survival rates of sweet sorghum were decreased,and antioxidant enzymes activity greatly changed.This study laid the basis for further work on breeding and improvement of sweet sorghum irradiated by 12C6+heavy ion beam.