谷胱甘肽及其类似物对小麦耐热性的影响

 利用冬小麦品种京都40和春小麦品种辽春17，以谷胱甘肽(GSH)，寡肽(GCG)以及合成寡肽GCG所用的谷氨酸(Glu)、半胱氨酸(Cys)和γ-氨基丁酸(GABA)3种物质组合作处理，清水作对照，研究高温胁迫条件下不同处理对小麦幼苗抗高温胁迫生理特性的影响，明确寡肽GCG的生理活性。结果表明，在高温胁迫条件下，200μmol/L的GSH和GCG处理可使小麦保持较高的相对含水量，降低叶片质膜相对透性和丙二醛(MDA)的含量，有利于维持细胞膜的完整性。同时，在高温胁迫条件下，GCG处理显著提高了幼苗对二苯基苦基苯肼(DPPH)活性氧自由基的清除能力，且叶片中抗氧化酶活性也被诱导增强，有利于缓解高温对小麦幼苗的伤害。与其他2种处理相比，GCG的处理效果最为显著。综合来看，GCG具有类似GSH的抗氧化活性，可以增强小麦幼苗对高温胁迫的耐性，因此GCG作为一种人工合成的寡肽，有望作为农业生产调节剂来开发应用。

Effect of Glutathione and Analogue on High Temperature Tolerance of Wheat Seedlings

In this experiment, glutathione (GSH), oligopeptide (GCG), and three substances including glutamate (Glu), cysteine (Cys) and gamma aminobutyric acid (GABA) were used as treatments, water was used as control (CK), two wheat (Triticum aestivum L.) seedlings Jingdu 40 and Liaochun 17 were taken to study the effects of different treatments on physiological characteristics under high temperature resistance, and furthermore to determine the physiological activity of the oligopeptide GCG. The results show that under the condition of high temperature stress, the treatments with 200μmol/L GSH and GCG are able to maintain higher leaf relative water content of wheat seedlings, reduce the relative electrolyte leakage and malondialdehyde (MDA) content, and conduce to the integrity of cell membrane. In the meantime, GCG treatment could significantly enhance the 1, 1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity in wheat seedlings under high temperature stress, and the activities of antioxidative enzymes are also improved to reduce the damage caused by the high temperature. Comparing with the other two kinds of treatments, the effect of GCG treatment is most significant. On the whole, GCG could enhance the high temperature tolerance of wheat through modifying the activities of antioxidative enzymes similar to GSH. Therefore as a kind of synthetic oligopeptide, GCG is expected to develop the applications as an agricultural production regulator.