中文摘要：

为探讨根系供水状况及叶面受光强度与生姜叶片活性氧代谢的关系，采用PEG．6000模拟干旱与遮光50％交互处理，研究了自然强光正常供水（T1）、遮光50％正常供水（T2）、自然强光模拟干旱（T。）、遮光50％模拟干旱（T4）条件对生姜叶片活性氧水平及抗氧化酶活性的影响．结果表明：胁迫处理6d时，生姜叶片O；产生速率、过氧化氢含量及膜脂过氧化产物丙二醛含量在午间均显著升高，但以L升幅较大，T4次之，T1、T2较小；而抗氧化酶除T，、T2的过氧化氢酶活性在中午较高外，各处理超氧化物歧化酶、过氧化物酶及L、T4的过氧化氢酶活性均在午间显著降低．持续处理过程中，T1、T2生姜叶片活性氧水平及抗氧化酶活性基本稳定，但以T1高于T2，而T3、T4活性氧水平均持续升高，保护酶活性则呈先升高后降低的趋势．表明干旱胁迫尤其是强光干旱交互胁迫可引发生姜叶片活性氧积累，而遮光则有利于维持较高的保护酶活性，降低叶片活性氧水平，减轻干旱胁迫的伤害程度．

英文摘要：

To explore the relationship between water supply in roots, light intensity on leaves and reactive oxygen metabolism, the effects of various treatments including natural light plus normal watering （T1 ）, 50% shading plus normal watering （T2 ）, natural light plus PEG-6000 simulated drought （T3 ）, 50% shading plus simulated drought （T4 ） on reactive oxygen level and antioxidant enzyme activity in ginger leaves were studied. The results showed that, 6 days after treatment, the 02 production rate and H202 and MDA contents remarkably increased in ginger leaves at midday. Treatment T3 showed the greatest increment, followed by T4, T1 and T2 in order. In addition, the activities of SOD and POD in all treatments and CAT in T3 and T4 noticeably decreased, while CAT in T1 and T2 exhibited a high activity at midday. Throughout the whole treatment, reactive oxygen level and antioxidant enzyme activities of ginger leaves in T1 and T2 remained stable, with a higher activity in T1 than in T2. However, the reactive oxygen level kept increasing in leaves exposed to treatments T3 and T4. Meanwhile, the activities of antioxidant enzymes increased firstly and then decreased. Taken together, this study demonstrated that drought stress, especially drought plus light stress, led to an increased accumulation of reactive oxygen in ginger leaves, while shading was conducive to maintaining high activity of protective enzymes, and therefore to reducing reactive oxy- gen level and alleviate drought-induced injury.