【摘要】 对叶面喷施240mg·L-1硫酸镁溶液后,烟草幼苗感染烟草马铃薯Y病毒脉坏死株系(Potato Virus Y-vein necrosis,PVYN)的发病情况、病毒含量及防御酶系活性进行研究。结果表明:烟草幼苗经240 mg·L-1 MgSO4处理,再接种PVYN后其发病程度减轻,病情指数及幼苗叶片中病毒含量均低于未喷施MgSO4的对照。叶面单独喷施MgSO4处理和喷施后接种PVYN处理,对苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)、多酚氧化酶(PPO)的活性均有较强的促进作用,烟草幼苗接种PVYN后,PAL在处理第6天时达到酶活高峰(2.63U·g-1FW),POD、PPO的活性在接种PVYN后第15天时产生高于对照处理的酶活高峰,峰值分别为55.76U·g-1FW和10.62U·g-1FW;但喷施MgSO4对过氧化氢酶(CAT)活性影响较小。本研究证实,MgSO4具有较强的诱导植物产生抗病毒的能力,可明显提高植株的抗病性。更多还原

【Abstract】 Foliar spray method was introduced to study the effects of MgSO4 with the concentration of 240 mg·L-1 on disease situation and defensive enzymes of tobacco seedlings after PVYN infection.The results showed that the disease index and the content of PVYN of tobacco seedlings treated with MgSO4 were all lower than that of the inoculation control.MgSO4 had a strong stimulative function on the activities of phenylalanine ammonia-lyase(PAL),peroxidase(POD) and polyphenol oxidase(PPO) when spraying on leaves.PAL achieved the peak of enzymatic activity on the 6th day after spraying MgSO4(2.63U·g-1FW),POD(55.76U·g-1FW)and PPO(10.62U·g-1FW)reached the peak on the 15th day,which were higher than that of the control.But MgSO4 had a weak influence on catalase(CAT) activity.This research confirmed that MgSO4 has stronger ability of inducing plants to resist virus and can significantly improve plant’s disease resistance.更多还原