γ辐射对高等植物防御系统的影响

EFFECTS OF GAMMA IRRADIATION ON THE DEFENCE SYSTEM IN HIGHER PLANTS

用^(■)Co—γ射线照射番茄干种子,分析其幼苗中超氧化物岐化酶(SOD)和抗坏血酸(ASA)的变化。结果表明,经50GY 照射后,植物机体内辐射防御功能加强,而100—500GY 处理的,植物防辐射功能下降,导致了辐射损伤效应。

Dormant seeds(with 8.5% moisture)of tomato were irradiated with (?)o γ—rays at0—500 Gy and grown under greenhouse conditions.The results showed that ascorbicacid(ASA)and superoxide dismutase(AOD)actiity were enhanced and free radicalswere effectively scavenged in the treatad seedlings.Such was believed to be one of themechanisms for the observed“radio—stimulation”since both ASA and AOD are con-bidered to provide an important defence to the plant.SOD activity and ASA content de-creased in the treaments of 100—500 GY,resulting in a decline in the function of de-fence system of the plant.