小麦不同品种叶片对光氧化胁迫响应的比较研究

Comparative Study on the Photooxidative Response in Different Wheat Cultivar Leaves

利用叶片浸水或甲基紫精 (MV )处理造成光氧化条件 ,研究了小麦品种 (系 )鲁原 10 2 (L Y10 2 )和 5 4 36 8对光氧化的抗性。发现在浸水处理诱导的光氧化条件下 ,小麦品种 L Y 10 2叶片叶绿素含量和可溶性蛋白质含量的降幅大于5 4 36 8。光系统 II最大光化学效率 (Fv/Fm) ,光系统 II电子传递效率 (ΦPS )和非光化学猝灭值 (N PQ) ,超氧化物歧化酶(SOD)和抗坏血酸过氧化物酶 (APX)活性等有相似的变化趋势 ;但在 MV诱导的光氧化条件下 ,5 4 36 8和 L Y10 2表现出与浸水处理相反的变化趋势。表明 L Y10 2对浸水导致的光氧化更敏感 ,而 5 4 36 8对 MV处理更敏感。利用叶黄素循环抑制剂二硫苏糖醇 (DTT)和 SOD抑制剂二乙基二硫氨基甲酸酯 (DDTC)预处理等方法 ,证明不同小麦品种对浸水处理和

Using the method of immersion in water and methyl viologen (MV) treatment in the high photon flux density(PFD), the tolerance of wheat cultivars LY102 and 54368 to the induced photooxidation was investigated. Under the photooxidative condition induced by immersing leaves in water, the leaves of wheat cultivar 54368 had a smaller decrease in chlorophyll and soluble protein contents than that of cultivar LY102 The similar changes in photosystem II maximum photochemical efficiency ( F v/ F m), the quantum yield of photosystem II electron transport ( Φ PSII ), non photochemical quenching (NPQ) values, superoxide dismutase (SOD) and ascorbate peroxidase (APX) activities were observed in cultivar 54368, indicating that 54368 had more tolerant to the photooxidative condition induced by immersing in water than LY102 In contrast, LY102 showed higher tolerance to the photooxidative condition mediated by MV than 54368 Further studies by using inhibitors(DTT and DDTC) showed that there were different photoprotective responses to different photooxidative stresses between two wheat cultivars.